So I have a 1985 Chevy C10 with a 262 v6 that I swapped to a 350 that I built. Its cammed and has Summit Racing Vortec heads. The block and accesorries were from a 1997 tahoe. Kept the accessory brackets and accessories but I got rid of the Vortec injection and put an Edelbrock intake and carburetor on it. I wish I would have watched this video when I was setting up my heater core and cooling system. I kept getting air trapped. I later figured out about the thermostat bypass. Great video!
Omg. Thanks man. I'm swapping my o school tomorrow to vortec heads. After all your vortec videos I decided to do so. Thanks for all your time and info !!!!
Thank You Thank You Thank You. So glad I subscribed and learned this very important coolant issue. I'm installing 059 Vortec heads on my 1985 Gen 1 SBC. I had no clue this was a thing. Drilling holes in the thermostat is a great work around.
i drill 2 1/8 holes in all my old small block thermostat since the 70's.. this trick also helps in case you stat sticks closed, not a cure.. but helps water flow and again case your stat sticks closed you have a lil some thing to get you to where can replace it.
Dealing with this right now as I'm using a mercruiser intake on my 4.3 Vortec block. The mercruiser used bypass through the marine exhaust manifolds (I presume), so no provisions on the intake to go to the water pump. Having to drill and tap a hole just below the thermostat to run a hose to the vortec water pump. (Using the mercruiser intake because it allows use of bigger, more plentiful LS style injectors, rather than the tiny 18lb/hr vortec injectors. 350hp NA is the target for this engine.)
Thank you for this video. I've been fighting an air pocket on my vortec head 880 block all summer. Watched this earlier today and drilled my thermostat and bingo it's gone. I drilled 4 5/32 holes I live in Michigan so won't be driving this winter. Much thanks too ya. You gotta new sub here😀
How’s it been going for u with the holes in the thermostat I’m doing the same thing to my 98 l31 350 I live in Warren Michigan so it doesn’t seem much winter either
very important information never dealt with vortec engines, so much info comes from your videos thanks. i'm working with a non roller block one piece seal good to know.
Awesome video Pat. Just finished my 383 build and didn't want to run vortec style water pump. I will drill 6 holes in thermostat and eliminate bypass hose. Thanks for the video!!
Interesting point , I thought about that once or twice I have had no problems so far , but then again I drill a small hole in most every one ! You only need one. Some of the newest cars have a piddle in thermo, that does the same thing ...it will also help a customer's if they have to add coolant it adds a constant bleed feature that aids a on the fly refill for the nongearheads that don't know much about cars . !
Hi I can across your video the other day. Last year I put a new water pump on my 77 350 sbc in my 39 chevy . It did not have the bypass hole on the water pump . Well I had a air bubble. Today I put in a new thermostat 180 temp . I drilled 6 5/32 in the new one . I drove it 26 miles and new got over 140 degrees. It was mid 40's here today in Kansas.
Hey man! 6 might be too many for you if your running a heater core as it bypasses coolant as well Also you should have a bypass on a 77 350 built into the water pump? What symptoms where you having to make you think you had a problem? If you look at the description in the video for suggestions in how many holes Two 5/32 holes would probably be better if your running a heater core
The water pump I got from speedway doesn't have the bypass hole In it . I asked them about it and they said it would on the street . I do have a heater core . After I put the new water pump on it would take a couple mile driving and the gauge would go up and the thermostat would open . Gauge would drop off and then go fully all the way around for a second then drop off to 180 and stay there. I'm going to take my old thermostat and drill 2 holes in it and put it back in .see what happens. Thanks for the help
@@cuttersperformance okay today I put in the old thermostat with 2 holes in it . Drove around 28 miles . Stayed around 160 on the gauge . 45 degrees today.
Thank you for teaching me about this mystery I have wondered about for three years! What I found online was how I would ruin my new engine if I didn’t plumb the manifold to the water pump. What I came up with was a silly looking copper pipe looped around! I learned about this thermostat technology in my Toyota class in 1988. It was called a “jiggle valve” and is such a primitive genius idea. I will make the modification you have outlined and use my existing bypass hose plumbing for my new propane fuel system.
Yeah exactly, alot of modern thermostats have a jiggle valve in them to prevent trapped air. The vortecs will need abit more than a air bypass and thats why a few holes are needed You will notice it will be super easy to bleed the cooling system with this mod aswell Thanks for checking out my video!
@@cuttersperformance I have been getting boil over when I close my heater core valve. Then it runs hot. Basically after watching your video I realized when I close the heater core valve that takes away the bypass. So I will use the other nipple off the water pump and go to the intake under the thermostat! Then I should be able to close my heater core for the summer months! (1969 Suburban)
Was it ever rebuilt? Does it have the factory heads with the steam holes? Proper head gaskets with the provision for the steam holes in the block and head?
I was just dealing with this. I have a 1979 block 383 stroker with the water pump bypass that I’m swapping into my 02 blazer. I’m using the 4.3 belt set up and needed a reverse rotation water pump but it doesn’t have the bypass. Now I’m confident that I can plug the block and use a bypass in my performer RPM intake 7101. I have the mid 90’s production World Products S/R Torquer heads. I’m assuming I don’t need to worry that they are not going to have the pump bypass anymore on the block. Awesome video. Thank you.
I always drill 1 head for it, and put that head on the passenger side. This really is an overlooked item, and guys never really understand what im saying when I bring it up. I only drill the 1 side so the heads can be swapped to block it back off IF the motor goes back into a Vortec truck in the future.
My prized smallblock is an early 880 Block thats drilled for fuel pump, drilled for steel timing cover, and drilled for water pump bypass on the head. I carb swapped it with a mechanical fuel pump, mild roller cam, drilled the bypass hole, and stuck a Vbelt system on it to go in my 86.
Just an FYI. I have only ever put a single 1/8" hole in the thermostat flange, to purge out any trapped air, and I have never had a hot spot problem. Personally, I think you are putting in too many holes, and too big of holes. Anyway. I like your content, you just got another sub.
great info, i got vortec heads just to get a small performance boost on my junker 360 sbc and i had no idea they blocked the internal block/head bypass for coolant flow. Ill have to check my manifold if i have a port to add a bypass hose to the pump or ill just drill the thermostat, hopefully i dont forget when the time comes to do it Also, out of curiosity, any port on the top of the water pump will do right? Do all the ports take coolant in or are the lower passenger side coolant out?
I just subscribed to your channel and in the past I've watched a ton of videos on the vortec heads and am looking to get my hands on a set of 062 set .. my question is I'm in Canada just across from Detroit.mi .. how much would you charge me to do a set for me with everything you've learned that will make the most power out of them .. ???? I did watch your video were you said that there wasn't much difference between 2.02 and 1.94 on the intake but you did say that there was a significant difference on the exhaust between 1.50 and 1.60 and should go with the bigger exhaust valve ... I'd be looking to put these my stock 350 and of course I'll be upgrading the cam and lifters as well as timing chain oil pump and water pump but at 5th same time I'm looking to retain my TBI setup .. now GM does make an intake to bolt to vortec heads with the TBI setup on top .. a bit expensive intake so I'm looking for another manufacturer that also makes the same intake style but definitely cheaper in cost .. you're input would be so much appreciated and thank you in advance .. you're Canadian neighbor
If you're using a OE serpentine belt, most setups will be spinning the water pump backwards so you'll need counter clockwise pump. All V belts need a regular water pump (clockwise)
Well done video, great information. Noticed the serpentine setup. Maybe do a video on how you changed things. This is a repeat comment, the original dissapeared.
@@cuttersperformance I've done something similar with 96- 2000 vortec brackets and short C4 vette pump with mercruiser pulley. Cut off the a.c. mount above the steering pump and bored a hole through the alternator bracket where the heater hose comes out the side of the water pump. Used a Holley aluminum vortec timing cover to fit underneath the shorty style vette pump. This is on an 880 block with vortec heads, E air-gap and carb. Less is more and mo' betta'!
@Ron Nelson i like your style man! You would have loved my vortech blower serp belt set up made from tpi brackets haha ran 11 secs with that set up, no belt slip
Ok, so @ 3:32 I got just a tiny bit confused? I have the old school block with pump bypass, and about to put my Vortec heads on (followed your every step to build them!), and not sure if I need to do anything or not? You said something about “you guys won’t have issues”, but wasn’t completely clear? Am I good, or do I need to drill the T-stat? Thanks in advance, Pat!!!! I love every one of your vids!! You’re awesome!!!
It helps but the thermostat is above heater core. Air always goes to the highest point. And that is right under the thermostat. My truck gave some problems and I considerd drilling holes but didtn't. I didn't want lose my heat or make it take forever to heat up.
hey brotha love your videos I have 880 block that does have 3rd hole on block so your saying if I use older water pump with vortec heads all i need is holes in tstat i dont need to run hose from water pump to intake doesn't that do same i live AZ so would it be good to do both
Great video. I have a SBC 350 Gen 1. I have plugged the intake and water pump bypass hose so there's no hose there. After seeing your video, i think i should put the bypass hose back from water pump to intake. Or can i just leave the outlets plugged but drill some holes in the thermostat.? Its either one or both, correct? I live in a very hot tropical country by the way. Cheers
Great video. What if I’m running an 880 block with no bypass holes and also running aftermarket aluminum heads that’s not drilled for a vortec style intake ?
Thank you. I learnt something today! Never had issues with my Vortec heads on old school block heat wise but I might drill some holes in my thermostat anyways.
@@cuttersperformance I’ll do it. I’m pulling the heads soon to drill the push rod holes to 1/2”. Too close for my liking with the 1.6’s. I’ll have the coolant drained anyways.
Hey Pat, why not just drill the bypass hole into the vortec head, I have both the block and water pump with the bypass. I have put a hole in the T stat for a long time to deal with the air issue.
I have a vortec block without the coolant bypass hole and I plan on using after market heads. So instead of using the ugly vortec water pump and the bypass hose to the intake I can just drill holes in the thermostat? Thank you for this video you have a new subscriber!
Thats correct, ive done it many of times. I actually drill one hole in thermostats that have a bypass. I find it makes bleeding the air out of the coolant easier and stops air locks. Try 2 to 3 holes to start and keep a eye on the temperature. If you notice it climbs way past thermostat temp then all of a sudden drops then you need more bypass holes. Too many holes will cause it to get to operation temp slowly or never. Cheers! And thanks for checking out my video
Ok.. So if I have a 1st gen block that HAS the bypass hole in the block and I want to use the vortec heads with the intake manifold bypass, which water pump do I need? Do I have to plug the bypass hole in the block in order to use a water pump that has the intake manifold bypass hose provision? Sorry If I seem obtuse ..
The vortec cylinder does not use in the inblock bypass so it actually blocks the hole on the deck surface. You can run the vortec water pump as it has the extra bypass hose but dont forget this is a reverse rotation pump and has to be used with a serpentine belt system. An old school water pump you can T into the heater hose inlet from the water pump
@@cuttersperformance now I’m even more confused? I have a mid 70’s block, with V pulleys, in a Jeep….. I’m about to swap on my 062 heads, and I’ve bought a new AC Delco water pump for my year engine…. I have to idea if my ‘89 Wrangler heater core is a shut off style or not? So I just drill a few holes and feel confident that I’m good? Or do I need to T into a heater hose, also? I’m lost now!
I am using a blueprint engine setup with the vortec style heads and the block doesn't have the bypass hole in it for the old style water pump that is going on it I am going to drill some holes in the thermostat after seeing your video on it so I don't have to run the hose from the water pump to the intake thanks for the information. But do I need to block off the bypass port on the water pump itself and what would be the best way to do this ?
Little late to the party here but, I’ve been blowing water pump gaskets by, what I think, is higher rpm before the thermostat is open. I’d like to install the bypass hose from the manifold to the water pump but not sure which hose to cut a tee into..
If you see this and answer I would be so grateful . I have a later block with the bypass. I’m using vortec heads that block the bypass. And I’m using a v belt direction water pump . From what I gather from this video . I can also just drill holes in my thermostat and be ok also right ? Thanks in advance . Awsome video
Yes, if you dont have a bypass, a few holes in the thermostat (follow directions in description) will stop the vortec tempature swing and prevent head cracking
So If I’ve got a stock vortec with the 062 heads, it would be recommended to drill the holes in the thermostat to keep the heads cool? I’ve heard they’re prone to crack
At 4:25 you point out a port on the intake manifold for running water bypass. I have that same intake (2716) and run 906's and I have my radiator thermostat in that hole and the one just above it (top right) as my bypass. My SBC 350 never gets above 200 degrees. Even at long idle like drive in. Q: can you use either intake hole for a water bypass running vortec heads?
Yeah either one should work for you as a bypass Most guys running heater cores without shut offs will have no issues, but I still recommend drilling the stat or running a bypass Cheers!
Just a thought if the holes in thermostat stop thermostat from opening motor could run too cool and circulation is slowed down cause thermostat is not opening as much. Even just two holes in thermostat can cause it to not open as much as it should.
Hey Pat, have you heard or know of any difference in the TBI block water pumps with internal bypass and the later vortec pumps with external bypass having any difference in heights for pulley alignment? Also if the pulleys themselves have different bolt patterns? Reason asking is I have a TBI 355 I rebuilt recently with refreshed 193 heads. But also have a set of 062's that I want to swap and do a carb conversion. My truck still runs like a slow turd and been having TBI issues. I've replaced every sensor, pigtail connector, vacuum lines, checked vacuum leaks, rebuilt TBI etc. I'm fed up with the TBI system. So what I'm hoping is to plug my internal bypass on the block, run a vortec water pump with external bypass going to my air gap 4150 flange intake I have to go with my vortec heads. But can't find useful information about the two difference for possible pulley alignment problems. Thanks in advance. Really appreciate your videos
So you want to add a vortec water pump and pulley to a TBI serp belt setup? Dang! I got did a scrap run and threw out any tbi water pumps that I had, but I'm pretty sure I still have vortec water pumps. If you email me at pcperformance1@outlook.com I can take any measurements you are looking for of the vortec pump
I drill a couple small holes in the thermostat so the water still flows a little. And I'll put a brake bleeder in one of the intake water ports near the thermostat housing
I do like serpentine belts. But im putting my vortec in a 72 4x4 chevy truck. So id like the engine to be clean of the big serpentine brackets. Can i just run the vortec bypass hose from the intake to a old school water pump, and everything work out fine with a V belt set up?
Would I need to do a bypass or just drill the thermostat like you said, my block is 85 vette 14010207, vortec heads off 96-98 truck, edelbrock performer intake 7116, front accessories waterpump setup from 89 truck, 383 cubes, thanks fire the video
@@thomasgilmore2337 if you are running a heater core without a inclined shut off you will have some bypass flow but I still recommend drilling that thermostat Don't let those vortecs see over 200f and they should last you awhile
Question I have a buddy with a 305 in his 87 monte carlo. He wants to put some 906 heads and vortec intake and carb and distributor. Will he run into any issues with the vortec heads on a 305?
Ok let me understand this correctly. If I have a block and water pump with the bypass, do I stink the hose from the intake to water pump? Sorry for all the questions.
@@juliodiaz8280 o sorry I thought it was a general question haha If your using vortecs heads your normal sbc bypass won't work You need to have a have a hose from the intake to the water pump or drill your thermostat
I am also running a third gen trans am with a T-76 I'm looking for a good set of turbo manifolds are those the CX racing single turbo headers they look like they won't interfere with my air conditioning but the crossover pipe might
Great video series, my current build uses 062's. my question is what head gaskets do you use, watching this video i notice you using what looks to be valve pocketed gaskets. I've only been able to find two types of vortec head gaskets, Cometic MLS Head Gaskets C5269-023 (.023) and Cometic MLS Head Gaskets C5269-027 (.027). have you found any more choices ?
My favorite head gasket for vortec builds is the Felpro 501SD (.041 compressed) They say they are not for performance but I know guys that use them boosted and nitrous and they work quite well. I have actually never used a mls gasket on a vortec head. I typically only use them on power adder motors
I am retrofitting an 02 4.3 V6 back to carburetor and HEI distributor. My intake manifold is an Edelbrock Performer, which does not have the port for the bypass. Can I just block the water pump bypass and drill the holes in the thermostat and be done with it? I could put an elbow up on top of the manifold and fabricate a bypass that way, but would rather not. Thanks for your help.
I'm loving your channel I have a big block 427 60 over so it's a 440 howards hydraulic roller cam afr265 oval port full cnc heads victor jr.intake 850 Holly hp carb my cam specs 235x242@50 618 lift on a 108 lsa it's a lil over 10 to 1 compression I was hoping for 550 hp or at least 525 but I think I'm a lil shy on duration Monday I suppose to go pick up a 358 small block that has a steel crank pink rods and a set of 67 corvette dubble hump heads with 202 x160 valves the guy claims the motor makes 450 hp . So if I do get it I might be interested in you working a pair of afr as cast 195 heads. Can't wait to see the people's build over your build complete oh by the way the 358 I was talking about only has like 512 lift flat tappet lunati hydraulic.
One more quest. So if I drill my 880 block where the extra wp hole is. I know it is not all the way through. Anyway if I drill it will I only need to drill one head deck surface on my 906 heads. Or do I need to drill both head deck surfaces.
My brother bought a Motown block and was having trouble leaking water from the water pump because he used an old-school water pump in the block did not meet up to the water pump plus it did not even have a hole in it for the water to flow through so we took the old school water pump threaded and blocked let Bypass in it but if he ever gets rid of the engine somebody else may have trouble leaking water from there if they change the water pump
Figured it out if I use my heater core running from my old school pump to my heater core from my core to my intake manifold I have a l31 block and vortec heads will I be good without even drilling into the t stat ?
Yes but you may find adding 1 or 2 small holes in the thermostat will help with temp swings from air trapped around the thermostat. Also helps prevent head cracks on vortecs
Can i run a conventional normal rotation water pump on a vortec block with vortec heads. Putting in a 79 squarebody work truck and it has hydroboost and dont want to convert to serpintine set up.
@@cuttersperformance so do i need to drill and tap and plug a conventional waterpump on the pass side where the hole would be in the block. I would imagine the waterpump would piss out of there.
Shouldn't have to block anything as the water pump bypass should be sealed off when bolted to the block. Just make sure you use the 3 hole standard sbc water pump gasket
hers the deal , i ordered a 350 crate engine 4 years ago , checked the block when i got it , 5.7 , i ran the code 96/99, but they put 305 mismatched heads on it , anyway its been on the stand for 4 years wrapped in plastic , they have changed the entire engine back to flat tappet , so im getting ready to change it back to a roller engine , vortec heads , rollers , cam , you know all that , i just went down in my shop and looked at my block and water pump , both have the 3rd hole in it , so when i get theses vortec heads ,,, is all i have to do is have the hole drilled in the head so the water can go through the pump into the block and into the head and thats it ? , or what else needs done ? i have the provision for the fuel pump , but im going to change the cam good lord willing back to the same spec cam it had , but what cam do i use that has the same vortec specs but with a fuel lobe on the cam , mainly just let me know what to do about this cooling system issue , if im following you right , all i have to do is have the water hole drilled in the head so the water can flow from the pump through the block up into the head ? is that correct ? and do i need to have both heads drilled or just the one , thank you very much , and by the way i called ATK VEGE where the engine came from and they more or less said im beat , your warranty ran out a year ago and thats it , regardless whether the engine was ever installed or not , thank you very much for any information you can give me .
First off, you'll want to verify that the hole is actually drilled all the way, which it should be as that engine is a TBI replacement. Heres what I recommend if you have the bypass through the block: -Drill the passenger side head for the water hole, using your old head as a reference and a head gasket as a template. -Drill one 1/8" bleeder hole in the thermostat, this helps with temperature swing and prevents head cracks 👍
What if I use a heater core back into my passenger side of my intake manifold will that work as a bypass my l31 does not have the 3rd by pass hole for the left side of the water pump but my water pump has that hole
This is really interesting. I have an 880 4 bolt block that has the bypass, the timing cover holes are drilled and tapped and it is also drilled for a mechanical fuel pump. A bit of a odd duck but perfect for my plans. Building it to replace a cracked block engine in an 1987 21' SeaRay boat.
There is certainly a wide range of different 880 blocks, almost like a crap shoot with everyone I pull apart. Ive seen 880 blocks where it looks like the coolant passage is drilled, but its not actually fully drilled, so be sure to blow some air through that passage to be sure.
@@cuttersperformance should I plug the bypass hole on the water pump? I will either drill the thermostat or run a bypass hose. Could I drill the heads and block for the coolant bypass if I don't want to run a hose from the pump to manifold like a big block?
@@robertries7774 A hose from the water pump to the intake will work. If the block has a coolant bypass you could drill the head. Or if your running a heater core you could also just add 2 or 3 small holes in the thermostat and you won't have the huge swing in temp when the thermostat opens
only ever drill a 1/8 hole in a thermostat as a air bleed . The factory only bypasses the coolant to one side only. Far better off using a bypass hose ( like a big block) . this stops the block & heads going into thermal shock as the thermostat constantly opens and closes. A thermostat is considered open at 8mm open and flowing its max.
I built a 350 SBC out of a 99 Tahoe. Both heads cracked as per usual. I replaced them with aftermarket AL. Heads, and now I am finding out about the BY-Pass hole. I assumed it was plugged from the factory, like the fuel pump. Yes, we all know what happens when you ass-u-me. I am going to attempt to drill and tap in the car. What is the plug/drill size? Or is there a brass plug I can knock in?
Update, no drill needed. My Hanson 1/8 pipe tap went right in no drilling needed. This was a fairly easy fix, but it would have been a whole lot easier before I installed the motor. Fan, fan shroud, and water pump, r and r.
I’m doing the same building a l31 vortec any updates on what you’ve done to fix ur problem without having to drill into the thermostat and if so how has it been holding up
@@rockfordhx2768 No issue what so ever. Just ran the tap into the third hole on the passenger side of the block. The old school water pump covered it. The L 31 water pump does not cover it because the heads sealed it. The new heads I used were made so they would work on the older blocks. It would have been nice if they mentioned that I would need to plug the exposed hole. The L31 uses a bypass hose on the water pump. So there would be no need to make a bypass hole in the thermostat. Maybe you are planning on using a different intake manifold? If so yeah that would be an issue if you were using the Vortec heads.
I have an 86' block. 1 piece rear main, BUT flat tappet cam. Non roller. It has the lower water pump bypass hole in the front of the block. But it always does overheat on first startup. I never could figure it out. Engine suffix code is DDL. Im wondering if the deck isnt drilled for the bypass. ? Its also factory machined for mech fuel pump and all the timing bolt holes. Its an odd duck.
All pre 96 blocks should be drilled for bypass and I actually have the exact same block as you sitting in the shop. 1pc RMS, flat tappet, 4 bolt main truck block
Only have 2 outlets on the water pump, large to radiator plug the small 5/8 to the heater, have the bypass in the front of manfold. Just wondering how I can run this 2 the water pump. Thanks
I have a 880 block without the coolant bypass the extra hole on the passenger side but my old school water pump has the extra hole I’m going to drill the hole what should I do from there
I would not advise trying to drill that. The older blocks have the bypass which is a hole from the right deck to the water pump, that would be pretty tricky trying to drill that from both angles. They may make a jig for that but ive never seen or tried it before
@@cuttersperformance ok so I purchased a 98 Silverado 1500 l31 complete motor heads are 062s I purchased a aftermarket intake and I wanted to use my old school pump from my older 350 I don’t have the extra hole in the 880 block what should I do from here is what I’m saying I’m putting a carb onto it just attach the water pump and go ?
If you want to use the silverado accessories then you will have to run the vortec water pump. If your using older accessories then a normal sbc water pump will work and the water pump gasket will seal the bypass hole against the block. If your not running a bypass a few small holes in the thermostat works wonders
@@cuttersperformance yes I’m using my old accessories from my 85 350 so my water pump has the coolant bypass extra hole cause it’s old school but my block doesn’t just install the pump the hole will lineup against the would be hole in the block for the bypass on the 880 but mine doesn’t have it
I put new Vortec heads on my 74 sbc. Decided to drill 2 1/8 holes in the thermostat instead of drilling the head. Having trouble with the system pressurizing, top hose gets hard as a rock while it’s running. Doesn’t overheat though, ran it today and it stayed around 180-200. Any suggestions??
The system is supposed to be pressurized with the cap installed. Typically around 15 psi, the pressure in the cooling system brings up the boiling point of the coolant from 212 degF to 240+ @ 15 psi.
@@cuttersperformance thanks for the response. I just watched your video completely and you recommend 4-6 5/32 holes in the stat, I’m going to try that. I know it has to be pressurized, but this is excessive
So if I have vortec heads on the engine I don’t need to worry about the bypass hole in the block? I can run a tbi pump on the engine to keep the reverse rotation? (vortec 880 block with the hole below the water pump bolt + mechanical fuel pump machined)
Hey, thanks for the video. It really helped a lot. I'm falling into the catagory of tapping and plugging the bypass hole, so I was hoping to ask a quet. I'm using a vortec water pump on an older sbc TBI (project). So I can just plug the bypass hole there, drill 5/32 holes on the thermostat but am confused what to do with the two connections on the vortec pump. Which one is bypass, and which is heater core? Thanks for your time!
So *looking at the engine* , the pipe off the water pump to the right is for the heater core. The pipe to the left is the bypass. You can loop the bypass hose to a barbed fitting on the intake
Do you have the temp probe for the gauge in the head or the intake? Often times you may not notice the temp swing with the probe in the heads. You can still get air pockets around the thermostat depending on the layout of the cooling system (rad height vs thermostat height)
Yes, you want some coolant circulation when the thermostat is closed. This prevents a large sweep in head temperature when the thermostat opens. It prevents head cracks and air pockets
If the pump bypass puts water in the passenger side head and the thermostat is closed there is no where for the water to return to. Water has to flow through the thermostat and into the radiator then back to the pump. If the thermostat is closed no flow.
No the water flows from the head back to the water pump from that hole Think of it as a return hole Check around 3 min mark in the video, hopfully that makes sense to you. I was just explaining the passage not the actual flow path and thats why I added the subtitle Cheers! 🏁
So I have a 1985 Chevy C10 with a 262 v6 that I swapped to a 350 that I built. Its cammed and has Summit Racing Vortec heads. The block and accesorries were from a 1997 tahoe. Kept the accessory brackets and accessories but I got rid of the Vortec injection and put an Edelbrock intake and carburetor on it. I wish I would have watched this video when I was setting up my heater core and cooling system. I kept getting air trapped. I later figured out about the thermostat bypass. Great video!
Omg. Thanks man. I'm swapping my o school tomorrow to vortec heads. After all your vortec videos I decided to do so. Thanks for all your time and info !!!!
Great info that I've never heard anyone talk about.
For all us old guys that didn't have vortec heads back when, thank you
I really wish you guys were on the west coast
Take care
Thank You Thank You Thank You.
So glad I subscribed and learned this very important coolant issue.
I'm installing 059 Vortec heads on my 1985 Gen 1 SBC. I had no clue this was a thing. Drilling holes in the thermostat is a great work around.
i drill 2 1/8 holes in all my old small block thermostat since the 70's.. this trick also helps in case you stat sticks closed, not a cure.. but helps water flow and again case your stat sticks closed you have a lil some thing to get you to where can replace it.
Jesus man Thank you. Explained everything very well and solved my overheating problem. Thanks for the help
Glad to hear man!
Thanks for the info, swapping vortec heads on my mercruiser 5.7.
Dealing with this right now as I'm using a mercruiser intake on my 4.3 Vortec block. The mercruiser used bypass through the marine exhaust manifolds (I presume), so no provisions on the intake to go to the water pump. Having to drill and tap a hole just below the thermostat to run a hose to the vortec water pump. (Using the mercruiser intake because it allows use of bigger, more plentiful LS style injectors, rather than the tiny 18lb/hr vortec injectors. 350hp NA is the target for this engine.)
Steve from Annapolis all these years I've been lucky never had that problem never thought about that good job thank you so much
No problem Steve!
Race on! 🏁
Thank you for this video. I've been fighting an air pocket on my vortec head 880 block all summer. Watched this earlier today and drilled my thermostat and bingo it's gone. I drilled 4 5/32 holes I live in Michigan so won't be driving this winter. Much thanks too ya. You gotta new sub here😀
Hey man! Right there is exactly why I do these videos
Soo glad to hear that!
Its amazing how well it works for such a simple trick
Race on! 🏁
You could also just get a thermostat with a rattle
How’s it been going for u with the holes in the thermostat I’m doing the same thing to my 98 l31 350 I live in Warren Michigan so it doesn’t seem much winter either
very important information never dealt with vortec engines, so much info comes from your videos thanks. i'm working with a non roller block one piece seal good to know.
Excellent video! I did not anything about that. I just don't know what I don't know. Thanks for the enlightenment.
Awesome video Pat. Just finished my 383 build and didn't want to run vortec style water pump. I will drill 6 holes in thermostat and eliminate bypass hose. Thanks for the video!!
Thanks for checking out my video. Check out the description, 6 holes is the maximum I've done. I find 3 is a good starting place and works for most
Interesting point , I thought about that once or twice I have had no problems so far , but then again I drill a small hole in most every one ! You only need one. Some of the newest cars have a piddle in thermo, that does the same thing ...it will also help a customer's if they have to add coolant it adds a constant bleed feature that aids a on the fly refill for the nongearheads that don't know much about cars . !
Can I like this video 100 times?
Nice tip! Lots of people don’t think about it.
Hi I can across your video the other day. Last year I put a new water pump on my 77 350 sbc in my 39 chevy . It did not have the bypass hole on the water pump . Well I had a air bubble. Today I put in a new thermostat 180 temp . I drilled 6 5/32 in the new one . I drove it 26 miles and new got over 140 degrees. It was mid 40's here today in Kansas.
Hey man!
6 might be too many for you if your running a heater core as it bypasses coolant as well
Also you should have a bypass on a 77 350 built into the water pump?
What symptoms where you having to make you think you had a problem?
If you look at the description in the video for suggestions in how many holes
Two 5/32 holes would probably be better if your running a heater core
The water pump I got from speedway doesn't have the bypass hole In it . I asked them about it and they said it would on the street . I do have a heater core . After I put the new water pump on it would take a couple mile driving and the gauge would go up and the thermostat would open . Gauge would drop off and then go fully all the way around for a second then drop off to 180 and stay there. I'm going to take my old thermostat and drill 2 holes in it and put it back in .see what happens. Thanks for the help
@@ilovedjing ahh ok you will for sure want some circulation, two holes should do the trick
Let me know how it goes
@@cuttersperformance Thanks for the help . I couldn't believe 6 holes made that big of a different . I will let you know how it goes
@@cuttersperformance okay today I put in the old thermostat with 2 holes in it . Drove around 28 miles . Stayed around 160 on the gauge . 45 degrees today.
Thank you for teaching me about this mystery I have wondered about for three years! What I found online was how I would ruin my new engine if I didn’t plumb the manifold to the water pump. What I came up with was a silly looking copper pipe looped around! I learned about this thermostat technology in my Toyota class in 1988. It was called a “jiggle valve” and is such a primitive genius idea. I will make the modification you have outlined and use my existing bypass hose plumbing for my new propane fuel system.
Yeah exactly, alot of modern thermostats have a jiggle valve in them to prevent trapped air. The vortecs will need abit more than a air bypass and thats why a few holes are needed
You will notice it will be super easy to bleed the cooling system with this mod aswell
Thanks for checking out my video!
Great info in the video! No one talks about the coolant bypass on the vortec’s. I’m certain this should fix the problem I’m having!
Are you experiencing a huge temp fluctuation?
@@cuttersperformance I have been getting boil over when I close my heater core valve. Then it runs hot. Basically after watching your video I realized when I close the heater core valve that takes away the bypass. So I will use the other nipple off the water pump and go to the intake under the thermostat! Then I should be able to close my heater core for the summer months! (1969 Suburban)
I just learned something new, THANKS!
I have a 77 GMC K25 with a 400 SBC that is prone to air pockets in the coolant, I will definitely be drilling some holes in the thermostat.
Was it ever rebuilt? Does it have the factory heads with the steam holes? Proper head gaskets with the provision for the steam holes in the block and head?
I was just dealing with this. I have a 1979 block 383 stroker with the water pump bypass that I’m swapping into my 02 blazer. I’m using the 4.3 belt set up and needed a reverse rotation water pump but it doesn’t have the bypass. Now I’m confident that I can plug the block and use a bypass in my performer RPM intake 7101. I have the mid 90’s production World Products S/R Torquer heads. I’m assuming I don’t need to worry that they are not going to have the pump bypass anymore on the block. Awesome video. Thank you.
Did everything turn out good I’m basically about to do the same thing with my stroker
Can I plug my block on my stroker also??
I always drill 1 head for it, and put that head on the passenger side. This really is an overlooked item, and guys never really understand what im saying when I bring it up.
I only drill the 1 side so the heads can be swapped to block it back off IF the motor goes back into a Vortec truck in the future.
Yeah very often overlooked! Good tip!
My prized smallblock is an early 880 Block thats drilled for fuel pump, drilled for steel timing cover, and drilled for water pump bypass on the head. I carb swapped it with a mechanical fuel pump, mild roller cam, drilled the bypass hole, and stuck a Vbelt system on it to go in my 86.
Just an FYI. I have only ever put a single 1/8" hole in the thermostat flange, to purge out any trapped air, and I have never had a hot spot problem. Personally, I think you are putting in too many holes, and too big of holes. Anyway. I like your content, you just got another sub.
great info, i got vortec heads just to get a small performance boost on my junker 360 sbc and i had no idea they blocked the internal block/head bypass for coolant flow. Ill have to check my manifold if i have a port to add a bypass hose to the pump or ill just drill the thermostat, hopefully i dont forget when the time comes to do it
Also, out of curiosity, any port on the top of the water pump will do right? Do all the ports take coolant in or are the lower passenger side coolant out?
I just subscribed to your channel and in the past I've watched a ton of videos on the vortec heads and am looking to get my hands on a set of 062 set .. my question is I'm in Canada just across from Detroit.mi .. how much would you charge me to do a set for me with everything you've learned that will make the most power out of them .. ???? I did watch your video were you said that there wasn't much difference between 2.02 and 1.94 on the intake but you did say that there was a significant difference on the exhaust between 1.50 and 1.60 and should go with the bigger exhaust valve ... I'd be looking to put these my stock 350 and of course I'll be upgrading the cam and lifters as well as timing chain oil pump and water pump but at 5th same time I'm looking to retain my TBI setup .. now GM does make an intake to bolt to vortec heads with the TBI setup on top .. a bit expensive intake so I'm looking for another manufacturer that also makes the same intake style but definitely cheaper in cost .. you're input would be so much appreciated and thank you in advance .. you're Canadian neighbor
Send me a email at pcperformance1@outlook.com
I can help you out
Hello Pat, what's your take on pump rotation clockwise or factory counterclockwise or does it matter?
If you're using a OE serpentine belt, most setups will be spinning the water pump backwards so you'll need counter clockwise pump. All V belts need a regular water pump (clockwise)
Well done video, great information. Noticed the serpentine setup. Maybe do a video on how you changed things.
This is a repeat comment, the original dissapeared.
Thats a custom serp belt I made from a original tpi third gen, I like how you noticed that haha 😄
@@cuttersperformance I've done something similar with 96- 2000 vortec brackets and short C4 vette pump with mercruiser pulley. Cut off the a.c. mount above the steering pump and bored a hole through the alternator bracket where the heater hose comes out the side of the water pump. Used a Holley aluminum vortec timing cover to fit underneath the shorty style vette pump. This is on an 880 block with vortec heads, E air-gap and carb. Less is more and mo' betta'!
@Ron Nelson i like your style man! You would have loved my vortech blower serp belt set up made from tpi brackets haha ran 11 secs with that set up, no belt slip
Ok, so @ 3:32 I got just a tiny bit confused? I have the old school block with pump bypass, and about to put my Vortec heads on (followed your every step to build them!), and not sure if I need to do anything or not? You said something about “you guys won’t have issues”, but wasn’t completely clear? Am I good, or do I need to drill the T-stat?
Thanks in advance, Pat!!!! I love every one of your vids!! You’re awesome!!!
If you are running a htr core it also acts as a bypass unless you have a water shutoff valve for temp control.
It helps but the thermostat is above heater core. Air always goes to the highest point. And that is right under the thermostat. My truck gave some problems and I considerd drilling holes but didtn't. I didn't want lose my heat or make it take forever to heat up.
hey brotha love your videos I have 880 block that does have 3rd hole on block so your saying if I use older water pump with vortec heads all i need is holes in tstat i dont need to run hose from water pump to intake doesn't that do same i live AZ so would it be good to do both
Run the bypass hose plus put two holes in the thermostat
thanks man I appreciate you and all you do
Great video. I have a SBC 350 Gen 1. I have plugged the intake and water pump bypass hose so there's no hose there. After seeing your video, i think i should put the bypass hose back from water pump to intake. Or can i just leave the outlets plugged but drill some holes in the thermostat.? Its either one or both, correct?
I live in a very hot tropical country by the way.
Cheers
If it's a hot climate. I would use the intake bypass as well as drill two holes in the thermostat to prevent air pockets
@@cuttersperformance Thanks mate.
Thanks for all your info. If i was to drill both vortec heads left and right would I need to drill my thermostat. I have a old block 73
No you wouldn't have to, but I'd recommend one hole in the thermostat. Really helps will trapped air and bleeding the cooling system
@@cuttersperformance thanks
Great video. What if I’m running an 880 block with no bypass holes and also running aftermarket aluminum heads that’s not drilled for a vortec style intake ?
Thank you. I learnt something today! Never had issues with my Vortec heads on old school block heat wise but I might drill some holes in my thermostat anyways.
Would highly recommend it! Try to keep those suckers from cracking haha 😄
@@cuttersperformance I’ll do it. I’m pulling the heads soon to drill the push rod holes to 1/2”. Too close for my liking with the 1.6’s. I’ll have the coolant drained anyways.
Learned
Seems like if you’re pulling the heads, then you should just drill the bypass hole through the deck. That would be the correct fix..no?
Thank You
Hey Pat, why not just drill the bypass hole into the vortec head, I have both the block and water pump with the bypass. I have put a hole in the T stat for a long time to deal with the air issue.
Has anyone tapped the bypass hole and plugged it off??????
I have a vortec block without the coolant bypass hole and I plan on using after market heads. So instead of using the ugly vortec water pump and the bypass hose to the intake I can just drill holes in the thermostat? Thank you for this video you have a new subscriber!
Thats correct, ive done it many of times. I actually drill one hole in thermostats that have a bypass. I find it makes bleeding the air out of the coolant easier and stops air locks.
Try 2 to 3 holes to start and keep a eye on the temperature. If you notice it climbs way past thermostat temp then all of a sudden drops then you need more bypass holes.
Too many holes will cause it to get to operation temp slowly or never.
Cheers! And thanks for checking out my video
@@cuttersperformance Awesome, thank you so much!
I usually drilled a 1/16" hole my t stats. I was trying not to affect it too much. It seemed to work.
Ok.. So if I have a 1st gen block that HAS the bypass hole in the block and I want to use the vortec heads with the intake manifold bypass, which water pump do I need? Do I have to plug the bypass hole in the block in order to use a water pump that has the intake manifold bypass hose provision? Sorry If I seem obtuse ..
The vortec cylinder does not use in the inblock bypass so it actually blocks the hole on the deck surface. You can run the vortec water pump as it has the extra bypass hose but dont forget this is a reverse rotation pump and has to be used with a serpentine belt system. An old school water pump you can T into the heater hose inlet from the water pump
@@cuttersperformance now I’m even more confused? I have a mid 70’s block, with V pulleys, in a Jeep….. I’m about to swap on my 062 heads, and I’ve bought a new AC Delco water pump for my year engine…. I have to idea if my ‘89 Wrangler heater core is a shut off style or not? So I just drill a few holes and feel confident that I’m good? Or do I need to T into a heater hose, also? I’m lost now!
@Dave n Karen put 2 to 3 holes in the thermostat, and you're golden,
I am using a blueprint engine setup with the vortec style heads and the block doesn't have the bypass hole in it for the old style water pump that is going on it I am going to drill some holes in the thermostat after seeing your video on it so I don't have to run the hose from the water pump to the intake thanks for the information. But do I need to block off the bypass port on the water pump itself and what would be the best way to do this ?
Little late to the party here but, I’ve been blowing water pump gaskets by, what I think, is higher rpm before the thermostat is open. I’d like to install the bypass hose from the manifold to the water pump but not sure which hose to cut a tee into..
What about older style heads with the bypass on a vortec block without the bypass? Drill holes in the thermostat to solve the problem?
Yeah you will have the same issue. Easiest way would be to start with 2 holes in the thermostat and try it
If you see this and answer I would be so grateful .
I have a later block with the bypass. I’m using vortec heads that block the bypass. And I’m using a v belt direction water pump . From what I gather from this video . I can also just drill holes in my thermostat and be ok also right ?
Thanks in advance . Awsome video
Yes, if you dont have a bypass, a few holes in the thermostat (follow directions in description) will stop the vortec tempature swing and prevent head cracking
So If I’ve got a stock vortec with the 062 heads, it would be recommended to drill the holes in the thermostat to keep the heads cool? I’ve heard they’re prone to crack
1 or 2 at least to prevent air pockets and cracks in the heads
@@cuttersperformance Thanks again boss!
At 4:25 you point out a port on the intake manifold for running water bypass. I have that same intake (2716) and run 906's and I have my radiator thermostat in that hole and the one just above it (top right) as my bypass. My SBC 350 never gets above 200 degrees. Even at long idle like drive in.
Q: can you use either intake hole for a water bypass running vortec heads?
Yeah either one should work for you as a bypass
Most guys running heater cores without shut offs will have no issues, but I still recommend drilling the stat or running a bypass
Cheers!
Just a thought if the holes in thermostat stop thermostat from opening motor could run too cool and circulation is slowed down cause thermostat is not opening as much. Even just two holes in thermostat can cause it to not open as much as it should.
Hey Pat, have you heard or know of any difference in the TBI block water pumps with internal bypass and the later vortec pumps with external bypass having any difference in heights for pulley alignment?
Also if the pulleys themselves have different bolt patterns?
Reason asking is I have a TBI 355 I rebuilt recently with refreshed 193 heads. But also have a set of 062's that I want to swap and do a carb conversion. My truck still runs like a slow turd and been having TBI issues. I've replaced every sensor, pigtail connector, vacuum lines, checked vacuum leaks, rebuilt TBI etc. I'm fed up with the TBI system.
So what I'm hoping is to plug my internal bypass on the block, run a vortec water pump with external bypass going to my air gap 4150 flange intake I have to go with my vortec heads. But can't find useful information about the two difference for possible pulley alignment problems.
Thanks in advance. Really appreciate your videos
So you want to add a vortec water pump and pulley to a TBI serp belt setup?
Dang! I got did a scrap run and threw out any tbi water pumps that I had, but I'm pretty sure I still have vortec water pumps.
If you email me at pcperformance1@outlook.com
I can take any measurements you are looking for of the vortec pump
I drill a couple small holes in the thermostat so the water still flows a little. And I'll put a brake bleeder in one of the intake water ports near the thermostat housing
I do like serpentine belts. But im putting my vortec in a 72 4x4 chevy truck. So id like the engine to be clean of the big serpentine brackets. Can i just run the vortec bypass hose from the intake to a old school water pump, and everything work out fine with a V belt set up?
Would I need to do a bypass or just drill the thermostat like you said, my block is 85 vette 14010207, vortec heads off 96-98 truck, edelbrock performer intake 7116, front accessories waterpump setup from 89 truck, 383 cubes, thanks fire the video
You can do either, but I would probably just drill the thermostat
Works well! 👍
@@cuttersperformance thanks, I didn't really realize that there was that much to a water system
@@thomasgilmore2337 if you are running a heater core without a inclined shut off you will have some bypass flow but I still recommend drilling that thermostat
Don't let those vortecs see over 200f and they should last you awhile
So what do you use to plug the hole with
Is there anything look for when buying late model 880 block
You have got a really great channel here my friend. Keep up the good work.
Thanks brother I appreciate the positive feedback
Question
I have a buddy with a 305 in his 87 monte carlo. He wants to put some 906 heads and vortec intake and carb and distributor. Will he run into any issues with the vortec heads on a 305?
He should be ok with the 1.94/1.5 stock valve size but any bigger will clip the small bore of the 305
@@cuttersperformance as far as water pump any issues?
Ok let me understand this correctly. If I have a block and water pump with the bypass, do I stink the hose from the intake to water pump? Sorry for all the questions.
@@juliodiaz8280 o sorry I thought it was a general question haha
If your using vortecs heads your normal sbc bypass won't work
You need to have a have a hose from the intake to the water pump or drill your thermostat
I am also running a third gen trans am with a T-76 I'm looking for a good set of turbo manifolds are those the CX racing single turbo headers they look like they won't interfere with my air conditioning but the crossover pipe might
Yes that are the cx racing manifolds
Do you have the air conditioning hooked up
Great video series, my current build uses 062's. my question is what head gaskets do you use, watching this video i notice you using what looks to be valve pocketed gaskets. I've only been able to find two types of vortec head gaskets, Cometic MLS Head Gaskets C5269-023 (.023) and Cometic MLS Head Gaskets C5269-027 (.027). have you found any more choices ?
My favorite head gasket for vortec builds is the Felpro 501SD (.041 compressed)
They say they are not for performance but I know guys that use them boosted and nitrous and they work quite well.
I have actually never used a mls gasket on a vortec head. I typically only use them on power adder motors
I am retrofitting an 02 4.3 V6 back to carburetor and HEI distributor. My intake manifold is an Edelbrock Performer, which does not have the port for the bypass. Can I just block the water pump bypass and drill the holes in the thermostat and be done with it? I could put an elbow up on top of the manifold and fabricate a bypass that way, but would rather not. Thanks for your help.
Instead of a HEI, check out a Progression Ignition distributor.
I'm loving your channel I have a big block 427 60 over so it's a 440 howards hydraulic roller cam afr265 oval port full cnc heads victor jr.intake 850 Holly hp carb my cam specs 235x242@50 618 lift on a 108 lsa it's a lil over 10 to 1 compression I was hoping for 550 hp or at least 525 but I think I'm a lil shy on duration Monday I suppose to go pick up a 358 small block that has a steel crank pink rods and a set of 67 corvette dubble hump heads with 202 x160 valves the guy claims the motor makes 450 hp . So if I do get it I might be interested in you working a pair of afr as cast 195 heads. Can't wait to see the people's build over your build complete oh by the way the 358 I was talking about only has like 512 lift flat tappet lunati hydraulic.
Usually just drill one 1/8th inch hole in the thermostat, some already have one.
One if they have a bypass is what I do usually
Hey bI've been doing that on all my cars bypass or not !
One more quest. So if I drill my 880 block where the extra wp hole is. I know it is not all the way through. Anyway if I drill it will I only need to drill one head deck surface on my 906 heads. Or do I need to drill both head deck surfaces.
I've never drilled the block for a water pump bypass
But yes only the passenger head would need to be drilled if the block has a passage for it
Great video! Super helpful!
My brother bought a Motown block and was having trouble leaking water from the water pump because he used an old-school water pump in the block did not meet up to the water pump plus it did not even have a hole in it for the water to flow through so we took the old school water pump threaded and blocked let Bypass in it but if he ever gets rid of the engine somebody else may have trouble leaking water from there if they change the water pump
So wether I got it or not it would be great to add no more than 4 holes if I’m following you right
If you got the by pass already I would try 2 holes
If you dont have a bypass, I find 4 works the best, and sometimes 6 if they run hot
Can I run old school heads on a no bypass block and put an external bypass from under the thermostat to a tee in the heater hose at the pump
Figured it out if I use my heater core running from my old school pump to my heater core from my core to my intake manifold I have a l31 block and vortec heads will I be good without even drilling into the t stat ?
Any info on the heater core
Should I drill the bypass hole on my vortec heads?
You can if your block has a bypass.
Drilling the thermostat like shown in the video works quite well though
Will the water flowing through the heater core back to the radiator do about the same thing? I have a set of 906s oh my 93 C10 TBI motor., 5.7?
Yes but you may find adding 1 or 2 small holes in the thermostat will help with temp swings from air trapped around the thermostat. Also helps prevent head cracks on vortecs
Can i run a conventional normal rotation water pump on a vortec block with vortec heads. Putting in a 79 squarebody work truck and it has hydroboost and dont want to convert to serpintine set up.
Yeah no problem
You just need to make sure you have some sort of coolant bypass when the thermostat is closed
@@cuttersperformance so do i need to drill and tap and plug a conventional waterpump on the pass side where the hole would be in the block. I would imagine the waterpump would piss out of there.
Shouldn't have to block anything as the water pump bypass should be sealed off when bolted to the block. Just make sure you use the 3 hole standard sbc water pump gasket
Can stock vortecs work on a 400Sbc + 040 bore. Stock pistons, comp came up fitted 9.2:1
So I have a 062 head with a vortec 350 and a 4.3 v6 vortec pump which doesn't use the bypass hole so I'm good right
hers the deal , i ordered a 350 crate engine 4 years ago , checked the block when i got it , 5.7 , i ran the code 96/99, but they put 305 mismatched heads on it , anyway its been on the stand for 4 years wrapped in plastic , they have changed the entire engine back to flat tappet , so im getting ready to change it back to a roller engine , vortec heads , rollers , cam , you know all that , i just went down in my shop and looked at my block and water pump , both have the 3rd hole in it , so when i get theses vortec heads ,,, is all i have to do is have the hole drilled in the head so the water can go through the pump into the block and into the head and thats it ? , or what else needs done ? i have the provision for the fuel pump , but im going to change the cam good lord willing back to the same spec cam it had , but what cam do i use that has the same vortec specs but with a fuel lobe on the cam , mainly just let me know what to do about this cooling system issue , if im following you right , all i have to do is have the water hole drilled in the head so the water can flow from the pump through the block up into the head ? is that correct ? and do i need to have both heads drilled or just the one , thank you very much , and by the way i called ATK VEGE where the engine came from and they more or less said im beat , your warranty ran out a year ago and thats it , regardless whether the engine was ever installed or not , thank you very much for any information you can give me .
First off, you'll want to verify that the hole is actually drilled all the way, which it should be as that engine is a TBI replacement.
Heres what I recommend if you have the bypass through the block:
-Drill the passenger side head for the water hole, using your old head as a reference and a head gasket as a template.
-Drill one 1/8" bleeder hole in the thermostat, this helps with temperature swing and prevents head cracks 👍
What if I use a heater core back into my passenger side of my intake manifold will that work as a bypass my l31 does not have the 3rd by pass hole for the left side of the water pump but my water pump has that hole
This is really interesting. I have an 880 4 bolt block that has the bypass, the timing cover holes are drilled and tapped and it is also drilled for a mechanical fuel pump. A bit of a odd duck but perfect for my plans. Building it to replace a cracked block engine in an 1987 21' SeaRay boat.
There is certainly a wide range of different 880 blocks, almost like a crap shoot with everyone I pull apart. Ive seen 880 blocks where it looks like the coolant passage is drilled, but its not actually fully drilled, so be sure to blow some air through that passage to be sure.
Good thermostat already have air bleed hole with small valve in it to block coolant flow )
Need more than a air bleed if your using vortecs
You need a small amount of coolant flow at all times
@@cuttersperformance - Heater always has coolant flow from heads to pump
Can I use a short Chevy water pump on my 383 Vortex build? All of my accessory drive pulleys are for a short pump.
Thanks.
Yeah you should have no problems. Just make sure you have some sort of coolant bypass
@@cuttersperformance should I plug the bypass hole on the water pump? I will either drill the thermostat or run a bypass hose. Could I drill the heads and block for the coolant bypass if I don't want to run a hose from the pump to manifold like a big block?
@@robertries7774 A hose from the water pump to the intake will work. If the block has a coolant bypass you could drill the head. Or if your running a heater core you could also just add 2 or 3 small holes in the thermostat and you won't have the huge swing in temp when the thermostat opens
@@cuttersperformance Yes running a heater core, probably just end up drilling the t stat.
only ever drill a 1/8 hole in a thermostat as a air bleed . The factory only bypasses the coolant to one side only. Far better off using a bypass hose ( like a big block) . this stops the block & heads going into thermal shock as the thermostat constantly opens and closes. A thermostat is considered open at 8mm open and flowing its max.
I built a 350 SBC out of a 99 Tahoe. Both heads cracked as per usual. I replaced them with aftermarket AL. Heads, and now I am finding out about the BY-Pass hole. I assumed it was plugged from the factory, like the fuel pump. Yes, we all know what happens when you ass-u-me. I am going to attempt to drill and tap in the car. What is the plug/drill size? Or is there a brass plug I can knock in?
Update, no drill needed. My Hanson 1/8 pipe tap went right in no drilling needed. This was a fairly easy fix, but it would have been a whole lot easier before I installed the motor. Fan, fan shroud, and water pump, r and r.
I’m doing the same building a l31 vortec any updates on what you’ve done to fix ur problem without having to drill into the thermostat and if so how has it been holding up
@@rockfordhx2768 No issue what so ever. Just ran the tap into the third hole on the passenger side of the block. The old school water pump covered it. The L 31 water pump does not cover it because the heads sealed it. The new heads I used were made so they would work on the older blocks. It would have been nice if they mentioned that I would need to plug the exposed hole. The L31 uses a bypass hose on the water pump. So there would be no need to make a bypass hole in the thermostat. Maybe you are planning on using a different intake manifold? If so yeah that would be an issue if you were using the Vortec heads.
I have an 86' block. 1 piece rear main, BUT flat tappet cam. Non roller.
It has the lower water pump bypass hole in the front of the block. But it always does overheat on first startup. I never could figure it out. Engine suffix code is DDL. Im wondering if the deck isnt drilled for the bypass. ?
Its also factory machined for mech fuel pump and all the timing bolt holes. Its an odd duck.
All pre 96 blocks should be drilled for bypass and I actually have the exact same block as you sitting in the shop. 1pc RMS, flat tappet, 4 bolt main truck block
@@cuttersperformance Mines a 2bolt. Fbody block iirc
That is a strange one, because the 86 fbody would have been 2 bolt but should have had a roller cam
Hi do you have any engine for sale
Only have 2 outlets on the water pump, large to radiator plug the small 5/8 to the heater, have the bypass in the front of manfold. Just wondering how I can run this 2 the water pump.
Thanks
Some guys tee it into the heater hose
@@cuttersperformance ok will do that, should I still drill 2 holes in the thromstat as well.
Great info!! Thanks.
I have a 880 block without the coolant bypass the extra hole on the passenger side but my old school water pump has the extra hole I’m going to drill the hole what should I do from there
I would not advise trying to drill that. The older blocks have the bypass which is a hole from the right deck to the water pump, that would be pretty tricky trying to drill that from both angles. They may make a jig for that but ive never seen or tried it before
@@cuttersperformance ok so I purchased a 98 Silverado 1500 l31 complete motor heads are 062s I purchased a aftermarket intake and I wanted to use my old school pump from my older 350 I don’t have the extra hole in the 880 block what should I do from here is what I’m saying I’m putting a carb onto it just attach the water pump and go ?
Just check out my recent upload and let me know what u think thanks man I appreciate it
If you want to use the silverado accessories then you will have to run the vortec water pump. If your using older accessories then a normal sbc water pump will work and the water pump gasket will seal the bypass hole against the block.
If your not running a bypass a few small holes in the thermostat works wonders
@@cuttersperformance yes I’m using my old accessories from my 85 350 so my water pump has the coolant bypass extra hole cause it’s old school but my block doesn’t just install the pump the hole will lineup against the would be hole in the block for the bypass on the 880 but mine doesn’t have it
I put new Vortec heads on my 74 sbc. Decided to drill 2 1/8 holes in the thermostat instead of drilling the head. Having trouble with the system pressurizing, top hose gets hard as a rock while it’s running. Doesn’t overheat though, ran it today and it stayed around 180-200. Any suggestions??
The system is supposed to be pressurized with the cap installed. Typically around 15 psi, the pressure in the cooling system brings up the boiling point of the coolant from 212 degF to 240+ @ 15 psi.
@@cuttersperformance thanks for the response. I just watched your video completely and you recommend 4-6 5/32 holes in the stat, I’m going to try that. I know it has to be pressurized, but this is excessive
@@EvanLightner304 read the description in the video on how many holes. 4 to 6 is the max.
Thanks man!!
So if I have vortec heads on the engine I don’t need to worry about the bypass hole in the block? I can run a tbi pump on the engine to keep the reverse rotation? (vortec 880 block with the hole below the water pump bolt + mechanical fuel pump machined)
Just have to have a hose from water pump to intake
Hey, thanks for the video. It really helped a lot. I'm falling into the catagory of tapping and plugging the bypass hole, so I was hoping to ask a quet.
I'm using a vortec water pump on an older sbc TBI (project). So I can just plug the bypass hole there, drill 5/32 holes on the thermostat but am confused what to do with the two connections on the vortec pump. Which one is bypass, and which is heater core?
Thanks for your time!
So *looking at the engine* , the pipe off the water pump to the right is for the heater core. The pipe to the left is the bypass.
You can loop the bypass hose to a barbed fitting on the intake
what about running a tbi serpentine setup and water pump with vortec heads.....?? mine had never run over 180?
Do you have the temp probe for the gauge in the head or the intake?
Often times you may not notice the temp swing with the probe in the heads. You can still get air pockets around the thermostat depending on the layout of the cooling system (rad height vs thermostat height)
What does the bypass do exactly? Do I need it?
Yes, you want some coolant circulation when the thermostat is closed. This prevents a large sweep in head temperature when the thermostat opens.
It prevents head cracks and air pockets
Good info 👌👊
What if I have the bypass and drill 5 holes? I was told to drill 5 holes by my buddy before I seen this video lol I’m also in Texas tho
Have you tried it? That's alot of holes when using a bypass. I would have done two. You may have super slow warm ups
@@cuttersperformance yeah my warmup are slow but doesn’t overheat anymore stays at 180 once the temps up. Is there any risk to running it like that?
Thanks!
Thanks Jay!
This was my 3rd vid and 15 seconds in I realized I'm not subbed.... 👉subbed
I appreciate that! Thanks for checking out my videos
If the pump bypass puts water in the passenger side head and the thermostat is closed there is no where for the water to return to. Water has to flow through the thermostat and into the radiator then back to the pump. If the thermostat is closed no flow.
No the water flows from the head back to the water pump from that hole
Think of it as a return hole
Check around 3 min mark in the video, hopfully that makes sense to you. I was just explaining the passage not the actual flow path and thats why I added the subtitle
Cheers! 🏁
Are you a Canadian Business?
Yeah im in Ontario Canada 🇨🇦
@@cuttersperformance Anywhere near Woodstock, or London, I’m from Woodstock looking for someone to help with the engine in my 67 Camaro
@@oxyfee6486 yeah within a hour. Feel free to email me a pcperformance1@outlook.com
@@cuttersperformance Finally, a RUclipsr I like who’s close, 😂 I will definitely be in touch, Thank You
I take those dart iron eagles off ur hands lol
Haha sorry man I'm building up a nice motor with those
I have a set of old school Bowtie heads that'll blow the doors off your vortec heads.
I drill a hole in every 1 I put in these old engines
Old school trick that works well
Oldsmobiles have a 5/8 bypass!