Troubled 400 Pontiac engine showed up in pieces! Problems and Solutions
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- Опубликовано: 31 дек 2023
- This 400 Pontiac engine was brought to me in pieces. The engine belongs to a 1970 Pontiac GTO convertible 4 speed.
In this video i describe the issues and why the engine was removed from the car. Then the process to analyze and correct each, one at a time. This is a work in progress and more videos to come. 
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You are spot on with the adjustable valve train. That camshaft has a slightly smaller base circle so using stock studs can cause loose valve lash. Be careful with lifters. Some companies started supplying sbc lifters for Pontiac. They do not have the oil band in the right spot so they can stop oiling at base circle making the really clatter at idle.
Thanks Steve, I actually compared the lifters to SBC and you are correct, the oil relief does not line up. AG
Also, Pontiacs had two different rocker arm ratios, so if anyone chooses a camshaft, ask the grinder if it's designed for the 1.6:1 or 1.5:1 rocker arm ratio.
Pontiacs have non-adjustable (except maybe Ram Air IV) and the camshaft manufacturers know this.
If the lifter isn't getting the oil, then the valve train isn't getting the oil either. You'd see a lot more wear especially on the exhaust valves. Measure them to be sure.
If they are stock rods, they would have little squirters on them to squirt up at the cam.... assuming they were installed correctly.
Love your channel, always have been a gear head and loved the engine machine work. I'd tear those plugs out and clean that piece as good as I could and put everything back in brand new. It's now or never is what I was taught. Money saved by using old parts always comes back to bite you in the behind. Good luck !
Good advice, thanks Dave. Thanks for the nice compliment. AG
HAPPY NEW YEAR 🎉 thank you for all of the great videos you made last year. I’m looking forward to seeing more great videos this year. You always go the extra mile to share your knowledge very much appreciated.
Very nice compliment, thanks STP. Happy New Year to you. AG
Much of the engine design is an artifact of the original 1955 287, at that time John DeLorean was a junior guy at Packard. Those main dowels are an example. Like most Pontiacs, it looks like your dowels are deep in the block. This is a bigger problem on 3.25 main blocks, but the 3 inch main 400 can still use improvement there. I remove all the dowels, and I try a much longer dowel of the exact same size that is commercially available. If things line up well with these, I will run them. If need be, I will fit the block and caps for a slightly oversize dowel. More work, but sometimes required to correct cap movement.
The intake closing ramp of the Comp XE cams is very fast, almost too fast for a Pontiac with a 2.11 intake and a 1.65 rocker. They need ample valve spring and proper lifter preload of .050-.060 to quiet the valvetrain. There are better lobe designs.
Cadillac also used the cast Armasteel connecting rods.
Thanks for the video.
and thank you V8. Lots of good info and your comment about the cam is pretty consistent with the others. AG
Just a suggestion. Because of the high failure rate people are seeing for the past 10 years with flat tappets, I purchased a set of Japanese hardness tester files. The cam core should be about 40C Rockwell and the lobes above 50C. Lifters should be at 50C. I also check the lifters for crown and they should match the taper of the cam lobe. Most cams are ground to a .002 difference when measuring from the front to the rear of a cam lobe, just what you found out. The lifters should have about a crown of 0015" with the highest point in the center of the lifter. Also, when rebuilding from scratch with unknown history of the block, the position of the lifter bores to the cam lobes should be checked. Tools are available or you can make your own if you have a lathe. I am gun shy with my build after checking a new set of Melling lifters. Melling uses the prefix JB and I assume that the J stands for Johnson. The crown on these was good on 2 lifters. The rest were a mixed bag with some having 0.003" crown, some were flat, some were flat and tapered to one side and I was disgusted. I purchased a set of Crower that they advertise as Johnson lifters. I measures the crown on them and actually replaced one with a better Melling. I compared the 2 brands, everything looked and measured identical after taking each apart (solid lifters), the oil holes in the exact same location, the oil hole size the same, the recess around the lifter identical down to the coloration. This reinforces my thought that the Melling lifters were manufactured by Johnson but who ground the taper on the bottom? It is not just the oil and I am saying this for everyone as I think you know most of this if not more. Seems as if quality control is out the window nowadays with everyone pushing expensive roller lifter setups and the factories not using flat tappets any more. Sad, did the equipment go bad? No training for new employees? Everything done on a Friday?
Lots of great information here, thanks for taking the time to provide valuable input. AG
I recently rebuilt a 455 and luckily did the first run on the engine stand. Near to no lifter rotation on any lifters. Tried a different set of lifters, still nothing. Looking at the wear pattern on the lifters had the contact patch running straight across the centreline of the lifter face. Checked the direction of the taper on the cam lobe. IT HAD BEEN GROUND ON BACKWARD! Summit cam. Purchased an eglin of a similar grind. Measured the taper now in the right direction. Assembled and fired engine to now find MOST lifters rotating but not all. Again tried a few different brands of lifter to no evail. Eglin cam only had just about a thou taper. Eventually bit the bullet and consulted with a local cam grinder who reground the core i already had and now all lifters are merrily spinning around. 2 brand new cams from different sources junk.
So they have this motor built by someone else. They list some “complaints” about noise? Fast bleed lifters make noise. Performance motors make noise. Timing issues will cause pinging and detonation. They take it all apart and dump it on you? Over what you have described as an ignition timing issue? Disassembled it? Ripped the cam bearing out? Why??? I’d call BS and walk away.
And before I do that here let me tell all of you some stuff. I’ve been building pretty much nothing but Pontiacs for well over 40 years. I run a 400 bored 30 over with a set of heavily ported #16 heads, a Comp Cams XE 274 cam, Smith Brothers Pushrods, #RHOADS LIFTERS, TRW forged fat tops and cast crank and rods. 10.66/1 iron head. 30° of initial timing with 6° mechanical and 14° in the can or ported vacuum. Holley Street HP 750 on an Edelbrock Performer and full length headers. It’s damn near the same motors as this one. We’re at 3200 feet of elevation. Flicks stars like a champ and screams like a banshee. On 93 octane pump gas. Never detonate. Not even to 6500 RPM. No matter how hot it is. So I don’t understand this motor or its customers issues. My guess is they had a severe ignition timing issue, went nuts, taking it apart and dumped it on you? Why remove the cam bearings? Unreal. I’d walk away. You’re jumping hoops for no valid reason. 10.66/1. Iron head. 30° of initial timing. At 2/3 of a mile high. 93 pump gas. Most will tell you it can’t be done but the proof is all over my page. This motor should run. And lastly, 99% of this who claim to know and understand Pontiac motors absolutely do not. Why you see so many 9.5/1 461 roller motors that don’t run any faster than solid lifter 400s did 50 years ago! Too much Voodoo. Not enough science. Lastly. Challenge conventional wisdom. That’s where the gains are. 😉
The detonation is a bad situation, an engine can't survive if someone keeps driving it and doesn't deal with it.
Correct, thanks David. AG
@@goldsgarage8236 But all the bearings looked great???????????? VERY strange as the rod bearings all should have been egged shaped 🤔
Because people brag on Compression ratio. They think the higher compression ratio makes the engine. Yet they need to understand. You are going to need premium fuel. Almost AVG gas range. Plus remove a lot of the timing to make it survive.
Great video. I'm looking forward to your next process video with the Pontiac 400 engine.👍
Thanks Steve. We will be making a follow up as the project progresses. AG
Happy New Year!
Very interesting and once again shows that there is more than one to do the same things.
Documentation of thoughts and conditions is a great tip.
These days with phones and digital cameras, I like to photo document things as they come apart, the time it takes pays off for me and the cost is negligible.
Sadly since this one was "in a basket" you didn't get that opportunity.
Anyway another great show, valuable to watch for the general info even if you never intend to touch a Pontiac V8.
Thanks Uncle. Thinking is harder than working but worth the effort. Happy New Year and stay tuned as we work our way through this. AG
So nice to see someone figure out the problem instead of just doing a complete rebuild. To many shops just want the money and move on.
Nice comment, thanks Terry. AG
Thank you for the dial bore gauge lesson.. that was my request.. Happy New Year AG!
My pleasure Ponga. I am sure many others appreciated it too. Happy New Year to you.
As always great content and always a learning experience!! Thank you!!!
Thanks for the nice compliment . More to come! AG
Great explanations with the background to understand what's going on. If this were my engine, I would not buy anything and send it to you. I'd have you buy the correct parts that you choose. You made a good point that you taking it apart would have found more and I'm sure the engine owner has enough capability that they pulled it apart looking for obvious problems. You did find that one obvious problem with the leaking valve that he sort of found with the low pressure but now, if I had that engine, I'd unbolt it from the car, pull off the accessories and ship it to you. Great video.
Thanks for the compliment Jack. The leaking valve was easy to fix, I just lapped it and it is sealed. AG
Crank looks wonderful!!!....very pretty........
Yes it does. AG
Happy New Year AG to you and your family.
Thanks for sharing.
I think the Pontiac can be fixed.👍👍
Happy New year Ed. Good to hear from you and always appreciate your advice. AG
I just found your channel. Great stuff! subbed!
Thanks Turbo, more to come. AG
Happy New Year to you too Allen!
Happy new year!, same to you Conservator, please stick with me in 2024, lots to come. AG
@@goldsgarage8236Hey, I’m sticking with you even if you wouldn’t want me too. 😉
Not too far of 10k subscribers!
Back in 1984, I had fully grooved bearings in a 400 with a Ram Air IV oil pump. The idea was to get more oil to the rods for higher rpm. Unfortunately I couldn't afford better rods like the 455SD rods ($110 each back in 1984!). Today I wouldn't spend a nickle on stock rods when Eagle and others makes a decent street/strip rod with bigger bolts and make from steel. Pontiac cast rods are limited to about 5500rpm on a 400 and 5000rpm on a 455. Exceed the rpm and you will egg the big end.
Mahle has a document talking about 1/2 grooved, 3/4 grooved and fully grooved bearings. Bottom line, the half grooved was nearly as good in oiling and much better overall load carrying. Mahle offers all 3, but recommends the 1/2 grooved.
The oil leak out the rear is the rope seal. Its a PITA - I usually put a bit too much rope in there.
As for pinging. Its pretty easy to get a 10:1 motor and if you put something like a smaller Com Cams - 268 cam, it will ping. Retard the cam 4 degrees and it might live. 280 Magnum cam better match for both a 400 and 455. I tried running a 252 and it pinged like crazy.
Are the bearings hammered? If they still have spring back in them the engine probably didn't see detonation. I assume the top of the pistons look clean.
There is no reason to run low pump up or whatever they call those lifters.
My motor had the big valves and the screw in studs. No issue with stock valve train.
Lot's of great information Confuse, I have both types of bearings available. Thanks you for taking the time to provide your input. AG
Really like your video. Not common to see anyone working on a pontiac. I like how you systematically solved the problems the customer told you about.
Most unmodified pontiac dport heads don't flow much past around .400" lift on the intake. Unless heads are ported, all that extra lift is going to waste. I would also check if the intake valves were ground with the correct 30 degree angle. Most machine shops don't know this about 4bbl Pontiacs using a 30 degree intake seat for better mid-lift flow. Pontiac d port heads from 67-76 were essentially very similar port wise, with the exception of combustion chamber size differences between 326-350-400-428-455's.
On the valvetrain, you only need a bbc straight 7/16 rocker arm stud to replace the pontiac bottleneck ones. The stock pontiac rocker is actually 7/16' where it rides on the factory stud. Then just some cheap self locking 7/16 nuts and your back to a zero lash adjustable vavletrain, which solves a lot of problems due to aftermarket parts and machine tolerences.
Most of the comp cams XE are designed for sbc and aren't ideal for stock pontiac with d port heads. A d port headed 400 pontiac with a moderate factory style S camshaft and stock iron Q-jet intake is actually a very efficient design. Many aftermarket dual plane pontiac intakes are worse performing than factory 67-72 cast iron intake. Pontiacs also used fully machined combustion chambers.
On the camshaft, it used to be the thing on a stock d port headed 400-455 to run a reporduction RAIV "T" 041 camshaft with rhoads lifters, to get the benefit of the reduced duration and lift at lower rpm but full lift/duration in upper rpm band, sort of like a cave man version of honda's VTEC. Lol
I would also check customers distributor and check total advance to see if it's too much for the cylinder pressure he's running. Also a lean jetting of carb and or a vaccum leak can contribute to preignition.
One last thing, I ran a lot of pontiacs back in the 80's. The achilles heel in pontiacs are the cast rods, they're great until they come apart. Usually with stock valvetrain, you never run into a problem but with a 4 speed car and missing a shift, lets hope the customer has a rev limiter at the very least for insurance. I bought a set of SD455 rods back in the 80's right from a GM dealer, part #485225. They were decent rods for the time, but todays array of good affordable forged aftermarket rods, there's really no reason to run a stock pontiac cast rod unless its a pooch automatic stocker granny car. Also, a good set of aluminum d port or round port heads would be worth the cost, for less weight, better flow and newer technology. Speedmaster has an offshore RAIV heads with a better tech heart-shaped combustion chamber than the edelbrock version.
Thanks JLH. Lots of good information from a Pontiac expert. That explains why the stock cams are only .407" lift. AG
Exactly. Only the RAIV, and SD455 received more than .407 lift.(excluding SD421) Those engines are as rare as hens teeth! lol @@goldsgarage8236
Hey brother, i've done that, it WORKS!!....yes, flush out afterwards, but it DOES clean the oil galleries, etc.....we did that samr thing on a 351 Mustang that was in the middle of wipin the cam (my shop didnt build it we were helping)....we went thru 3 oil filters, spinnin the oil pump with a drill.....when we were satisfied, we stuffed a new cam in it, broke it in properly, and it runs today HAPPILY!!...yep!!....Attention to detail!!!.....only way to go!
Thanks for watching and commenting. AG
Good stuff....I never have found mix and match on valve train components to be a great practice, Especially on Pontiac I use too run Comp Cams products on my 400 Pontiac back in the day. My 77 TA 6.6 well 400 I actually over Cammed and never had an issue on the Street...I used a 305 Magnum Camshaft and ran the mortal soup out of it... around 70,000 miles with Castrol changed every 3,000 never a issue and she was always ready for a Race
...
Thanks for the info Jean. AG
Thx for showing your Dial Bore gauge Zero out calibration & cylinder Bore measurement proceedure.....Quite the Clean "Mystery" engine to Look & Measure that good After finding Metal particle Chunks !! ....Pontiac Oem factory cast Rods always worked good for me even on 6000+ Rpm Solid lifter built engines !! .....Really weird Full groove Main bearings there....1960's Pontiac blocks Always seem to run Hot & ignition Ping on 0.030 & up Overbores.....The 389 & later Stock engines seem to be on the ragged Edge of Overheating symptoms for some reason & big Overbores Don't help....Wouldn't adjustable Locking rocker arm Nuts fix the Pushrod/Lifter issue ?? .....Gonna be a good Reliable strong 400 Poncho when finished !!
Thanks for the info Tom. As for your question about the adjustable rocker arm nuts, I haven't mocked it up yet, but it is possible that the the nut will hit the step in the bottle neck before proper adjustment is achieved. AG
Thank you for the information
Thanks you for watching and commenting Bill. AG
The xe series of cams for pontiacs tend to be noisy and the typical discription is like a sewing machine or typewriter . So that is pretty normal. The choice of flat tappet lifters is crucial as quality has been a real problem in recent years. I would recommend Comp DLC lifters or Johnson lifters out of Mich. Len Caverly
Thanks Len. My producer Mike Kimble is a Pontiac guy and has done lots of research on this. His comments are exactly the same. AG
I was going to say the same thing, built a 454 years ago and reset the lifters 3 times thinking I was missing something. Turns out those XE grinds are just noisy.
John DeLorean wasn’t with Pontiac when the StratiStreak V-8 was designed in 1953; he was still at Packard.
I think you are correct Steve, thanks for the info. AG
I'm sorry you're having such bad luck with Pontiac its my favorite. I hope it changes for the better
A few things I have found with nosey Pontiac valve train issues, Mic each of the rocker studs where they make contact with the rocker ball & rocker on the stud, check to see if someone used 1.65 Ram Air IV rockers as they WILL ware funny and can be noise. Also look real close at both ends of the push rod, they can get really to hot (lack of enough oil) and be a issue as well. One time I had a set of the factory push rod guide plates rubbing on the push rods! I had to drill out the mounting holes on the plates with a carbide oversize drill on the Bridgeport Mill, and adjust the plates to line up correctly with the push rods. Valve trains can be hard to find the problem. One thing I do know in assembling any motor, there is no such thing as TO CLEAN ! pull them gally plugs and wire brush all them oil gallys 3/4/5 times, hot tank it twice and keep cleaning !!!!
Thanks for the info Hydroy. You have some detailed experience with Pontiacs. AG
Happy New Year. Great video and I am currently building a 68 Pontiac 400 out of my 68 GTO. I am curious what you think of the camshaft? I have the same one to install in mine and have been bouncing back and forth with leaving that or going roller. Mine engine still has stock design pistons and the stock 16 heads which I measured at 75cc’s. I have done the BBC stud upgrade just gunshy of the lifters and stock rod bolts. Thank you for all the hard work.
I would recommend calculating your static and dynamic CR and cranking pressure before you decide. Summit calculator doe static, Wallace for dynamic. Try for 170-180 PSI, you may have to change pistons. The point is, you don't want a big cam with low CR. Roller cams are great if you can afford one. I wouldn't worry about the rod bolts. AG
Happy New Year. AG
I just picked up another 400 today with 6x-8 heads so I have more options at compression. Everyone is steadfast about 9.5 as a maximum with iron heads on 93 octane but I run a 94 454 which started life as a TBI engine and I converted from the heads up to 96 Vortec complete with the port fuel efi manifold and larger injectors. The compression ratio is 9.0 to 1 and I run 87 octane in it in my 6500 lb dually and drive it daily.
I also already have the cam in the Pontiac. I have just been putting off starting it but have drawn alot more confidence from your break in videos.
I've heard of many complaints about Com Cams lifters.
Me included, 5 years ago put together sbf with com hyd flat tappet lifters . Was noisy from day one, sounded just like solid flat tappet , not an oil psi issue (idles at 60)Comp Cam dealer told me this is kinda normal. Surprised me he admitted that. All looked perfect when removed. Ben told they have to much clearance between plunger and inside body of lifter.
Thanks Frank, many similar comments. AG
Thanks for the video and I do love Pontiacs. If possible it would be great if you mentioned what the stock compression was with original flat top pistons and were these heads the original heads? - I think you mentioned the engine code at the beginning of the video, but I did not catch it. Thanks!
Mike Kimble is my Pontiac expert, Mike can you please respond to this question? AG
Also, unless you're mad at yourself or under a huge time crunch, you're money ahead to pull all the plugs out and get that block and all passages cleaned out. You might get away with not doing it but is it really worth taking a chance? Especially when you're trying to show folks the right way to do things.
Also good advice. Thanks. AG
Hi AL, great channel. A couple of questions: Will the Moroso oil screen you showed fit a SBC, and is the part number 23845? This is what I found on Amazon, but it does not say if it fits a SBC. Thanks.
Thanks Brad. Correct, 23845 is the same one that I have. IT fits SBC and many other applications also. AG
I would look into a cam with a wider lsa . 110 on a hi compression pontiac on the street is trouble. Ping Ping Ping . We enjoy the channel sir.
Thanks for your comment Col. AG
Pontiac used fully grooved aluminum main bearings on their ram air and ho 400 engines so that the rod bearings got 360 degrees of oiling . The 455 engine had a cross drilled crank..
Thanks for the info Tim. This was new to me. Now I have both sets. AG
Lastly,
I wud like to apologize to you sir, for blowin ur comments o the chanel, as i said b4, i get spun up seein a Poncho build, and MUST chime in, but i feel like New Years beer, may have made me be a bit of a pain......just know i LOVE the chanel, and hope to enjoy the Pontiac build, and MANY from ur shop......just wanted to apologize if i miffed you, was not my intention....TY SIR!!
No apology necessary. Thanks for watching and commenting. AG
@@goldsgarage8236 TY, you are kind!!.......lets get that Poncho properly put together!!!....
I’ve got a 4 bolt main 428 16 heads 70 goat runs great
Thanks User. Always appreciate info on Pontiac's. They are very unique. AG
Back in the day the trick on Ponchos was to replace the stock rocker studs with bigblock chevy rocker studs, then go to the Pontiac dealer and buy a set of 1.65 rockers (stock is 1.5) and a set of BBC rocker balls and locking nuts.
Thanks for the comment Richard. Check for push rod interference with 1.65 rockers. AG
The bearing with the hole and groove in it is the top one(in the block). The groove helps feed oil to the bottom bearing that has less groove or no groove (in the cap). Not sure what you were trying to say about the bearings?
Anyway, Happy New Year Al!😎👍
They do come both ways. The full groove feeds the rods better, the half groove is better for high loads/high performance. Clevite 77's come half groove. AG
thanks
If the main, & rod bearings are clean, the journals are perfect, the filter looks like it did its job. Removing those plugs might be a bit overkill especially considering it would need machining/ facing again.
Thanks Randy, you are making a good point, it is a dilemma right now. We also have to do something about the quench so it may have to go to the MS anyway. AG
Pick a cam other than a comp XE cam if you want a quiet cam the ramp design makes it more noise prone, I believe Bill Little makes reference to this in one of his video he made with you.
thanks Mark, seems we have consensus on that point. AG
FWIW, anecdote, but when I rebuilt mine a few years ago, one of the (new) rod bearings had two uppers, rather than a matched upper and lower. Also Clevite 77's. So your experience may be similar, in that the bearings were not packaged properly.
Thanks Harry, that could be a dangerous situation. AG
Happy New Year! I wonder how many rare pieces like this are left out there just sitting in huge piles waiting to be discovered...or shredded cuz nobody bothered to check!
Good point, Happy New Year. AG
Love your channel. Pontiac 400 you didnt mention the connecting rod is offset and builders error when assembly. Also the block design has weak main saddles and crack where the oil hole is.
Thanks for the info Rich. AG
Use a good sealant on the REAR oil gallery PLUG. I once used the wrong sealant and oil leaked out, thinking it was the rear main seal. To prevent bearings from spinning, rebuild the big end on rods to the small side of spec for more crush.
Chevy big block exhaust pushrods are about 1/8" longer and are used for small base circle cams. I think this is correct?
Thanks for your comments Keith. We are now going to use Johnson Pontiac lifters, so the stock push rods should work. I will check the geometry on assembly. AG
Viton rear 1 piece rear main seal from BOP Engineering worked great for me.
Thanks Eric. i have never had a leak with them. AG
will you be using a thinner head gasket and/or decking the block alittle to improve quench?
Yes, watch for updates on this project. AG
pontiac performance main bearings had a full groove for improved oiling because pontiacs were famous for spinning rod bearings.
Thanks Vhehn. Good info. I will use the full grooved bearings. AG
It was a normal design to have the oil passage in both main bearings in high output Pontiac 400s. My 350 hp 400 from 1970 had a full windsge tray, inner valve cover oil deflectors a 60 psi oil pump and full groove main bearings
Thanks, good info on this subject. AG
Yes fully grooved main bearings provide constant oil delivery to the rod journals, and in Ford 385 series the truck engines normally got fully grooved, some of the car engines did not.
I would recommend pulling the oil gallery plugs and cleaning the passageways. I owned a '67 GTO Convert for 35 years, now my brother has had it for the 20. The engine has been built 4 times. Debris (carbon or metal) will build up in the passageways and starve the lifters for oil. Also it could run the cam bearings dry. Not saying you will find anything, but just saying the owner has come this far.
Good advice Jim, the block is at the MS for just that purpose. AG
Just because an engine dynos with no issues, doesn’t mean that what’s going to happen once someone shoves it in a car! You should know this! How is the fuel tank, fuel line, fuel pump? Exhaust, ignition system? Was timing double checked once it was started in car? Hopefully someone is smart enough to check the timing, & have fresh fuel! You can kill anything, no matter how perfectly it was built! Customers don’t seem to understand that!
Good points Brian. I agree entirely and have seen this happen also. AG
I have seen those Pontiacs with failed cam bearings before. It would follow that lifter noise could be oil pressure leaking from the cam bearings, and would explain much of of the remaining evidence.
Thanks Gary, i wish i got to see them, but they are gone. AG
Good information and thanks for sharing.
Having a problem with a “rebuilt” Oldsmobile 350 engine
Is there an email I can use to ask your opinion about it???
Sure Jake, you can email me at allangoldconsulting@live.com. AG
Sounds like the guy got a cam and lifters without the right pushrods, rocker arms, and valve springs. With the leaked down on the valves the valves were hitting the pistons and bent them which all the previous stuff I mentioned would have caused the problem from the beggening. Just a guess. I've been learning more of this stuff for a 390 fe build.
Thanks for your observation Wk. I will be checking all that out on the rebuild and making videos of the progress. AG
I had similar problems with a Ford 302, turns out I had the main caps on backwards, causing the oil seal to leak and the bearings to grind up.
Thanks for the comment Pack. That would do it for sure. AG
I frequently use a next Size Larger hex Wrench ground Down flat on Front & all 8 Flats to a Tight Non-Slip fit for hex Plug removal Without stripping.....Prior torch Heating the Threaded Block area to Break-down the thread Sealant helps Successful removal.....Hope everything breaks loose Without using the Easy-Out !!
Thanks for commenting Tom.AG
1. those pistons are fairly low in the hole for GM. most GM pistons are .015 in the hole. with those being .025 in the hole, i would shoot for a .015-.020. thick head gasket. that will reduce the quench height and help eliminate the pinging. and if it was pinging as much as you said i would have wanted to see the rod bearings. i am betting it was pounding out the rod bearings. And that was one source of the metal flakes.
2. it's possible that the metal fakes were from the rod bearings if they were starting to fail. detonation is hell on the upper rod bearings. i would mic the big end of the rod and make sure they are still round. same goes for the rod journals on the crank. that crank looks ok.to the naked eye, but a micrometer will tell you the truth. around 12:58 you can see some scuffing on the crank fillet were 4 rod would be located just below the oil hole. at a minimum i would have the crank re polished, just to be safe. also, it looks like there could be dust or metal flakes on the crank at the same point in time. but that could also be from assembly lube and dust in the air.
3. since there were no cam or rod bearings to look at. my assumption is the cam was also starting to go flat as well and just had not failed yet. .002 is quite a bit of wear for a newly rebuilt engine with fairly low miles. here is what i would do. Replace the cam with and aftermarket roller. flat tappet cams require a minimum of 1400ppm ZDDP to live a long and happy life. every oil for sale at the parts store are SN rated. SN rated oil can only have a maximum of 800ppm ZDDP. so, what i am saying is. that no modern SN rated oil is safe for a flat tappet cam long term. there are other oils out there like AMSOIL Zrod and Lucas Hot Rod and Classic Car. both are over 1600 ppm ZDDP, but most parts stores don't carry it and you have to special order it. i use Lucas Hot Rod and Classic because it has a rust inhibitor additive package for cars that are stored over the winter. i use it in everything flat tapped after 1000 miles of break-in. I use Driven 30w Brake-In oil for the first 30 minutes to break in a flat tappet cam. then change the filter and drain the oil and refill with more Driven 30w Breaking oil for the next 500 miles. then repeat one more time for 500 miles. then switch it over to Lucas Hot Rod and classic the rest of its life. as a general rule, i will not use a flat tappet cam in anything that is not a matching number restoration on something like LT1 350, LS6, L78, L71 or L72, DZ302 etc. its simply not worth it with the current state of modern motor oil. you are much better off with a moder retrofit hydraulic roller in everything. there are very few engines that don't have modern retrofit roller cams available. the difference in cost between a roller cammed engine and a Flat Tappet engine is around $600. and for that money you get better performance, better longevity and the ability to use any modern engine oil. basically, what i am saying is that there is no reason to use a flat tappet can, unless you are doing a special number matching restore or a retrofit roller is not made for your engine.
4. the oil seal. i use the GST racing 1 piece oil seals for small and big block chevy. they look exactly like the one you got from BOP. in fact, i would bet 20 dollars they are from eh same manufactures.
5 the "360 Degree oiling" main Bearings were a big thing for a while. they were supposed to improve oiling to the rods for a full 360 degrees. but the truth is they lower the amount of bearing surface available for the crank to ride on. I know the pro-stock guys went to "3/4" or "270-degree" bearings years ago. for a hot street motor, you don't need it. stay with standard 180 degree bearings.
6. For any engine, i prefer to keep the dynamic compression below 8:1 to avoid detonation and obtain best performance. the XE268H Cam is a little small for a 9.7:1 engine, that results in a 7.98:1 dynamic compression ratio based on that XE268 cam and the 9.7:1 compression ration. I would step it up one cam size to at XE276HR or a Howards 414495-12. I don't like the comp XE line for street driven cars. the 110 lobe separation angle crates low vacuum and narrows the power band from peak torque to peak horsepower, which is fine in a street/strip car but for a street driven car, i prefer a 112 or 114 lobe separation angel. it widens the power band between peak torque and peak horsepower and has better vacuum for power breaks. the 112-degree lobe separation on that Howards cam would be much better on a street driven engine.
Wow, lots to absorb here, thank you for taking the time to share your knowledge and experience. AG
So Much More Time and Effort to have to Go Behind another Shop or Mechanic. Thanks for Sharing
Thanks David, lot's of valuable parts there. We have to figure out what happened first then fix it. It will run again. The block is at the MS now. AG
timing/lean conditions sound like the issue. 91 octane no less. I would do a valve job on both heads to help flow and seal valves properly
Thanks for the comment Utah. AG
friend has a ram 3 4 speed GTO around that yr, deciding to stick in an LS for now, says tell owner to look into the Grand Cherokee steering box mod its a cheap great mod
Thanks, did you say LS?
@@goldsgarage8236 yep I tried,, poor car has sat since prob 1980 in a building
Pontiac crankshafts are not cross drilled so they only oil the rods 1/2 revolution. The answer is to use full groove bearings or cross drill the crank. If you use the non-grooved lower shell you need to cross drill the crank.
thanks Steve, AG
What type of Dyno was used ? Rear Wheel or an actual Engine Dyno ?
WHY was the Block not squared up/Milled to "set" quench as desired ?
Thanks for the question Dirt. It was an engine Dyno. A can't answer your second question as i didn't build the engine. AG
I'm an 'amateur car mechanic' but a professional motorcycle mechanic (only built car motors for myself)
60 thou, not ideal LOL, yep, seems a bit much to actually work as a quench area.
How do you work out dynamic compression?
I've always used max 210psi cranking (around 300rpm) as a maximum cylinder pressure before you get problems.
The cam overlap will determine cranking pressure
'Armasteel' was the Pontiac designation
I really should make a video showing the easiest way to set up a bore gauge, I see 'everyone' doing it the 'conventional' way (yourself included)
I used to teach people 'how to'
Don't you have to mill original stud pads when fitting BBC studs?
Thanks Crazy, I would like to see your video on dial bore gauges.
I used Summit's CR Calculator, then Wallace DCR Calculator, it is accurate and fast.
i will stick to my 180PSI max, remember, I have not control over what happens after the engine leaves my shop. Thanks for the input. AG
@@goldsgarage8236 Ah, had not thought of that. It makes a lot of sense. If I can't control whats happening with engines I'm a lot more conservative and usually stay closer to factory specs. (except for some porting and cleaning up airflow)
I've been thinking of doing a short video on bore gauge set up for quite a long time but grandson would rather I watch him making shorts.
Edited to add; I'll make a camera mount with 1/4"x20 thread for tripod and get around to dial bore set up vid
@@goldsgarage8236 I was just watching Max Grant, he uses almost exactly the same method I was teaching.
It's at about 32 minutes to 33 minutes, showing what is easiest way to set bore gauge and definitely easiest way to teach someone how to set one. The only difference, I have the 'wheels' same side as micrometer barrel.
ruclips.net/video/I3jEiH4-f3I/видео.htmlsi=2H1rif95ihtfdrm8
If it has a oil groove in the lower part of the main bearing that is so it will oil the the crank better...
Thanks Leonard. AG
pull the plugs, tank it, jetwash it, and do it right....your just setting yourself up for failure if you don't......and to pull those plugs, heat them with a torch, let them cool CLEAR down, and then use a HAND impact driver to remove them. (the heating and cooling will break them loose, and the Hand impact will get them started)
Thanks Skipper, that is exactly what we are doing. The block is at the MS now. AG
There’s also checking for out of round and taper i didn’t see you do
Thanks John, I can't show everything, but i hid check and that was all good. AG
Is that a #'s matching engine or is it just pieces parts. It looks to be well machined, and no reason for it to be pinging unless it had poor fuel or too much advance. Had a few back in the 60's-70's and under a heavy load, going up a mountain with the A/C on it could ping a little, due to poor fiber cam timing gear and or too much advance. Going to custom cam, oddball lifters, replacing rocker arms and pushrods is, to me, just a cluster _ _ _ _. Good luck with that build.
Thanks for watching and commenting Robert. AG
11:20 mark, the #2 rod assy is in the #1 cylinder. Hope that didn’t get assembled that way..
Good catch Tony, for some reason the other side of the rod was marked #1, so there were two rods marked 1&2, 2 more marked 3&4, etc. In each case the piston install is determined by the location of the valve reliefs. Thanks for watching and commenting. AG
when you face a head geometry can change enough that your other interfacing part need thought out
Good point Jack.. Thanks for the comment. AG
If you're going back in with a flat tappet cam I would not use that used cam with new lifters. Spend the money on a new cam so the cam and lifters can break in together. The only way you should reuse a flat tappet cam is if the lifters are in good shape and you are certain they are going back on the same lobes. I'm sure people have gotten away with doing other sketchy stuff over the years, but it's not worth the risk.
Thanks for your advice Big Mike.AG
The rocker arms are probably non adjustable? AG
Not with these studs. AG
Arma steel was what pontiac called the casting crank and Rods
Thanks for the info Larry. AG
IF YOU WANNABE SMOKEY AND THE BANDIT, YOU MIGHT WANNA WATCH ⌚ THIS....
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Thanks Craig. AG
you incorrectly checked the deck height, if you check at the top of the piston you need to rock the piston all the way in either direction and find the average or check it directly over the piston pin. Len Caverly
Thanks Len. AG
Is the customer using the factory cast steel connecting rods ?
Yes, lots of detail on this in the follow up video that we published today. AG
I don't think I would hotrod a engine with cast rods. It seems counter intuitive. Happy new year.
It was a special cast alloy, I think it was called ARMASTEEL, come on will correct me. They work fine for street engines. AG
I meant, Some One will correct me. AG
think ford 302 GT 1970s ran fully grooved mains --bigends then have constent oil feed
good point, thanks AG
I would have taken those leaking valves out to see what was going on there. Bent valve, debris on seat/face? Galled valve stem? BTW it doesn't hurt to stick a magnet on the oil filter. It'll keep break in debris in place.
Scrap it first oil change.
Put the magnet back, always.
And use Chevy rocker nuts or just jam nuts.
Thanks Victor, only one valve was leaking, I have removed and lapped it and it is good now. I will do a high pressure leakdown test when the short block is assembled. AG
I forgot to add that installing a roller cam in a Pontiac is nearly a no go most of the time due to the fact that the foundry never put enough metal in the valley to support the lifters. You are stuck with the constant problems of flat tappet cams on these engines and that's a shame. Also the cylinder heads have pretty miserable flow and none of the factory heads were really any good even the stuff they considered high performance.
Thanks Mike, great in depth knowledge about Pontiac's. AG
PLENTY of Pontiac V8 out there happily running roller cams. ..
How do you know machine shop rip off the engine cam in apart
Thanks Jim, you are correct, we don't know. We are just asking the question?? and trying to figure out what happened. stick with us and I will try to get it right. AG
in 23:03 Vaslin for what uses? Thanks
good observation K3. i use Vaseline to seal the plexiglass plate on the combustion chamber when i am using the burette to check the CC volume of a cylinder head. The fluid is Windex, AG
thanks sir, I started using Vaseline to break up flat tapped camshaft with good results so far. @@goldsgarage8236
Someone installed all round mains to feed the rod bearings more oil mod probably like you do to an olds.
Good info, thanks. AG
Inside diameter of the bearing and ouside of the crank rod and mains... Torqued.
Oldsmobile and Pontiac use the same lifter. Maybe they used chevy or buick lifters.
Thanks Kevin. That is possible. AG
Sure hope that Mallory doesn't get slung out of that
Thanks for commenting Tim. AG
I'm a Poncho dude, but it doesnt take that to accertain a wiping of the cam.....WHAT OIL DID THE OWNER CHANGE TO ?????....mite be his bad......backfiring is an intitial cause of wiping a cam......sorry, i may be wrong, i'm only 2:37 into it.......
Thanks, the cam is not wiped. AG
Ok, so it wasnt wipin the cam......I LOVE BEING SHOWED WRONG, i'm just a worry wart, and want ALL things to be proper......THANK YOU for lettin me whine, and i am THANKFUL that i sub'd To the chanel......i get spun up on Poncho builds, and wanna chime in my 2 cents worth......THANK YOU again, for allowing me to whine.......i still am NOT a fan of the #12' heads.....#16, 48, or 62, if u want to make power.......altho i dont like its port shape, on a 455, the #64's will work, but good luck finding a set, i'm trying to say i believe i over-stepped my bounds, and i hope u understand my whining.....so, i APOLOGIZE for jumpin the gun, as ur expertise of tear down/forensics (if u will) are showin the issues......i get to spun up, as i LOVE Pontiac engines, my 462, Kauffman heads, nets 11 flat in qtr (3450 lbs).....pump gas......so forgive my rant please
No problem, thanks for the input. AG
There are some 455 pontiacs with 4 bolt main
Thanks Larry, yes I just learned that. Thanks for the info. AG
@@goldsgarage8236 great video like your content
A tip for you, just put the oil pump back on w a clean oil pan. Put 3 quarts of diesel fuel in the pan and prime it until all the passage ways are flushed out. Oh ya and a new filter also.
Thanks for the suggestion Racer. AG
Maybe flat cam?
The cam is in good condition. AG
Arma steel rods. They are junk, but not as bad as there reputation. With a light piston there just fine. However with rods being cheap today i don't run them.
Thanks for the comment Kevin. AG
Absolutely start from scratch on this one.
ALL caps & plugs removed, Clean, inspect, measure and >Verify Everything
Thanks Yafois. That is exactly what we are doing. The block is at the MS now. We are also decking it .018 to correct the quench. AG
@@goldsgarage8236
Glad to see this done, taking it on straight!
This set you back on your heels a bit I sense due to the extent of what occurred.
Only one way to Mae a machine right, is from the specs, and go from there.
YES the #12 heads shud be 72 cc........not a great head for flow....the early #16's or #48's have a better port shape, AND have material to blend/shape a bit......i had #48's on my first motor, with a back cut (30°) on the intakes....still runs today (build was 1983).....all NUNZI stuff....you DO know who Nunzi was rite??.....hope so....my brother and him used to have lunch weekly, back in the 80's......just sayin
Thanks User. AG
Hey Mr. Gold. I’m going to share a link on how to remove those plugs.
ruclips.net/video/BhRb4bbx_vI/видео.htmlsi=zNGUOzmswZb4wN8w
Thanks Hugh, i have removed many rusted in plugs with a torch, thanks. This sometimes the only way to remove them. The Pontiac plugs are not rusted. The problem is that they were pipe plugs but the they have been milled flush to the block and there is insufficient depth (about 1/8") to insert an Allen wrench deep enough to remove them.
Thanks for the link. AG
I understand. This way will get them out to the point the feel finger tight.
People resist the idea because of where the heat is applied.
Heat just the plug and it will get very loose.
Pontiacs are a strange engine as well as Buicks and Oldsmobiles, especially if you are used to Chevrolet stuff. After working with all of them it's easy to see why they were dropped in favor of putting Chevy engines in all the GM cars long ago. Too many weird issues with them plus none of them made the power that the Chevrolet engines did. The Pontiacs with their cast rods that broke at low rpm was a real show stopper. The Buicks with their terrible aluminum oil pump housing was real bad and Oldsmobile had some issues as well. The continued use of a rope seal was kind of stupid for as long as they did it too. All of the BOP line was designed for large heavy cars that needed plenty of low end torque and not much rpm to make any horsepower. They were all great for that and did it well. Great video, I can relate to your findings.
Thanks for watching and commenting Mike. AG
First of all that cam is too small for higher compression if distributor isnt optimized.
9.7 is decent compression for todays gas.
Now SBC lifters work fine in Pontiacs but not the other way around. Ive built many Pontiacs and used SBC lifters with no issue.
Now on Pontiac heads to mKe the valve train adjustable GM used to sell hardened washers to go under the rocker nut and you use SBC nuts.
If you want more quench deck the block to about -0.010" to -0.015". If not to -0.005".
If its not gonna be rpmed you can zero deck it easy enough.
As for yhe oem Pontiac rods they are Pearlitic Cast Iron and are GARBAGE. RPM LIMIT OF 5000-5500 MAX considering it has good bolts.
Id jump up to 280 series and look for closer lobe center line to bleed low end peak cyl pressure.
I built my first 400 back in 87, ran closed chamber heads and flat tops and ran a short duration cam and itwould rattle its head off above 3500rpm , should have ran a RA3 or RA4 copy cam.
Built a reind a similar engine, my old heads and upped the cam and it will run up to 5000 with no rattle. With 66 cc chamber it wont need huge initial timing maybe 10-12 btdc.
Also make sure seals on timing cover are new and spacer plate isnt pitted bad and look for a water pump with cast full length vane impeller ir it will have hot spots .
Also DO NOT USE AUTOLITE PLUGS.
Look for AC Delco or NGK plugs, step up to HEI too.
Thanks for all the info Monza. We are decking the block. AG
Why wouldn’t you just start from scratch. It’s all disassembled now hot tank it if it was me spend all the money then come to fine out there’s trash in the block would really suck
Good advice, thanks Robert. AG
ALL SD 73-74 were 4 bolt mains
Thanks User, I did not know that. See, I am still learning from you! AG
Full goove mains rods get oil all the time
Correct, thanks Michael. AG
Or even #62's, ALL had same chamber volume, but more meat to massage.......was never a fan of #12's...my #62's, stock, gave me a 12 flat qtr in a 3550 lb car, with a 244@.050 cam
That is a good E.T. for that set up. AG
I know Hex plugs Have only 6 flat sides !!!