I'm with you LT, regardless if it was worth it or not. The fact that you can and you did the swap is just cool and honestly why not, right. I enjoy watching this build solely due to the fact that it is not a high end build that costs you your first born, and is totally achievable in your own garage.
@@LawrenceTolman you are for sure better than the guys on there now. I know I am a master mechanic watching a show for normal people but, dang they play up the tiniest thing.
4:27 does a killer burnout & in the same breath, “ I can’t figure out for the life of me why this truck is wearing out rear tires!” Guy fukken rocks! 👍😎
I think it's pretty cool that LT takes the time to read and reply to so many comments. Also, he doesn't get defensive and blast a bunch ppl taking up for the 5.3l. Obviously 5.3's are cheap and awesome, no better bang for the buck, etc. This 8.1l swap is super cool and waaay more unique.
I’ve always sorta-kinda wanted to build a short box standard cab 2WD ‘SS 496’ (throwback to the ‘90s 454 SS trucks) half-ton Silverado with the 8.1L drivetrain. Of course it’d be black, with custom decals in the same font and everything as the old 454 SS trucks, I think it’d be cool. I figure the 8.1 with just an intake, headers, exhaust, and a tune should be kinda a rocket with stock reliability forever, vs. building a 5.3. No way would it fit in my Colorado, though, and it’s genuinely fast with a factory 5.3 and factory 4.10 gears.
I have a Yukon XL 2500 8.1 with 4.11 gears. Aftermarket tune, catback exhaust and new high flow cats. I just did a 300 mile round trip and got just a tick over 12mpg, premium. Still totally worth it. This engine is a gas diesel. So much torque available right off of idle.
I have an 01 2500hd with the 8.1/allison combo. Upgraded form a 1/2 5.3 Towing is night and day. I can tow 8k and the 8.1 rarely if ever comes out of overdrive. Loads of torque. When it downshifts towing it only runs about 2900 rpms. I love it. Only problem I haven't figured out is how to drag a gas station behind me yet. 10 mpg town/hwy.
8.1 is very reliable and easy to maintain. Mpg not great but when comparing I bought my 04 hd2500 almost 6 years ago with 40k for 23500$ shipped to my front door all fees included (1500$) shipping. Oregon to Texas. The same truck with dmax at time was at least 10k more plus ttl here. I love it. Had to put fuel pump on it because of how it was stored prior to purchase. But only valve cover gaskets since. 140k now. No regrets. I have 33s allison and recently 4.56 gears. Still 10 mpg combined driving. Sorry so long just wanted to inform non owners. Myself and 3 friends all daily 8.1s. Mine is lowest miles. One friend over 300k never out of truck only gaskets, plugs, wires.
Thank you for making these videos! There is not much content covering the 8.1. These are such badass engines. I drove a UPS truck with 8.1 Allison combo, it took a beating every day for years. I have an 8.1 suburban and really looking forward to seeing what you do with ugly truck.
I think 14-15 mpg is a bit optimistic, even with overdrive. The 8.1's were notorious gas guzzlers when new. 3000 rpm at highway speed is pretty high IMO. However, as a fun, joy ride type toy, it's a great ride! Also, great production quality in this video. Very well done. Reminded me of a episode of Stacey David's Trucks show. 👍
@@LawrenceTolman i'd do it all at once. the ring gap and compression might be an issue. maybe a cam to work work with the turbo would be wise though i don't think that would be needed to just get it going. the stock valve springs and rockers might need to be addressed to. the springs are weak, and bearings give out if you get too crazy on ls engines. it sounds like you might though i know the 8.1 is a bigger block and i think it's not actually a "ls engine". i love the idea of a sleeper btw awesome idea. got ideas for my little ranger.. was thinking a 302 built up but not sure. that ls in 3/4 ton is nice and anything in that family with a cam..
Love ya LT! Been watchin you since you first started on PB. Definitely have matured and are more comfortable as a video host. Keep up with it, looking for more Truck Tech.
I knew someone here in California that had one of those 8.1s in a long bed dually and he put a Gear Venders Overdrive box behind the Allison and towed triple axle horse trailers in the winter and new 5th Wheel RVs all summer and last I heard there was over 600,000 miles on the stock drivetrain. Other than the usual alternator, waterpump, and fuel pump here and there the only issues were intake gaskets (twice),plastic intake manifold (once),crankshaft sensor(twice), rear main seal and the high pressure line on the hydoboost system(both at once) but with that Allison/GearVenders combo he was getting decent fuel mileage and only replaced the brake pads once about every 80,000 miles!!!!!
Yeah people hate them cause you can't throw a bigger turbo on them and dump a bunch of black smoke out the back like a Duramax or a Cummins. They might have more fans if they were optional in half tons, but gas big block heavy duty trucks, that really hasn't been a popular thing since the 80's/early 90's, the Dodge Cummins pretty much changed the world 30 years ago away from gas engines in heavy duty pickups.
@@LawrenceTolman Check your tire clearance, I’ve seen a tire Spaghetti like that it was because the tire was rubbing against the wheel well when accelerating/or carrying to much weight.
Great truck mod and what a interesting swap to a big block. Looking forward to future mods. Your knowledge from HP tv is a added bonus. Thanks for sharing. Fan from Sydney Nova Scotia
It's a good bang for the buck truck. I'm closer to $5K on my swap, but I changed the transmission, had to source brackets for the Squarebody swap, and did headers and a segment swap on the PCM for the 4l80e. But....Big Block! For comparison, you cannot get into an 8.1 2500HD even with 200k+ miles for under $12k, and....Big Block.
Ah, the peeling clear coat on the hood and roof is an all to familiar sight lol but I'm starting to think my 02 Silverado might be the "uglier truck" :(
Well, I hope my 5.3L never needs replacing, but if it does, this confirmed my decision to drop an 8.1L in. My worries then are the 4L60E and G80 diff in the rear😆
I can tell you from experience that truck would be more fun and feel faster with a much higher rear gear. As in 3.08s or 3.55s. With 3.08s it would feel like a rocket ship on the highway and still have plenty out of the hole on street tires. Very low gears in a truck like that would only be useful if pulling a heavy load like a large camper or towing a race car. Low gears are also great for smaller high reving engines
Loving this series! Keep up the good work, you clearly know what you're doing. I own a 2001 Sierra ext cab 5.3. I recently just added 2inch lowering shackles and it got rid of the infamous GM rake. I'm digging the 4/6 drop on yours! I'm probably not gonna turbo mine but will put a stronger trans, camming it, and perhaps swapping gears in the rear end. Thanks for the inspiration!
I did a 5.3 to 6.0 with h/c/I in my 1500 silverado. I haven't gotten it dynoed so I cant say what power it makes. But after seeing your videos, if I could do it again I'd 8.1 swap it, dont get my wrong. The 6.0 is great and fun but 496 is just so much cooler. And I can tell you I have wayyyy more then $3000 total into everything in my truck so the 8.1 swap seems to be alot better of a budget build. Not to mention depending on your area or what kind of deal you can find changes the price. My 6.0 in the same situation as your 8.1 was only $1350
410s -430s is good, 3200 stall, cam. All it need lolol hell I do 2700 rpm in my 454 slammed obs crewcab with 410s with a 4l80e. Long trip I can do 300 on a tank. But city highway I do about 240 per tank. About 16-17mpg combined ill never sell mine... love the swap and truck man!! Stay different !
I'd love to put an 8.1 in my 96 Buick Roadmaster sedan. The LT1 does okay, but it really needs a lot more. I only get 12-16 MPG anyway, so I might as well have a bigger engine
@@LawrenceTolman going off of what William stated, you should do a segment on what kind of aftermarket support there is for this engine. Would be good information to know.
I have an 04 with an 8.1 and 4.10 gears and love it. I pull a 32ft camper and my boat with it and it's an excellent tow rig. The mpg sucks but I also have never needed to fork out thousands of dollars (just for parts mind you) to replace head gaskets or injectors on a Duramax. That motor is extremely reliable, Mercruiser offered the package for boats and I remember reading that they tested the 496 at wide open throttle for 500 continuous hours and it held together. That being said someday I'm still going to sell my truck to my dad once I find a clean low mileage cat eye Duramax with no rust 😂 I look forward to this build!
There are a lot of ways to get those numbers from a 5.3 to start.. but the difference will come later with add on’s as the bar is raised, so will the separation from the two.
I stumbled across a company called Raylar Engineering in my research of this very same swap for my 03 Silverado that actually makes what appears to be good parts for these 8.1 Vortecs, forged stroker cranks and aluminum cnc ported heads could make that a whole lot more fun
I had a 02 Avalanche 2500 4x4 with the 8.1l it was 373 geared and I had folks with 6.0 and 6.2 trucks ask me what in the hell do you have under that hood we cant keep up!...so yes the 8.1l is a total different ball game!..mabe a game changer!
I have an old carburated 460 big block out of an 80's E-350 RV I want to stuff into my ugly 2002 F150 once I kill off the bone stock 4.6 modular that's currently in it. After the engine swap I want to cage and back half it. I'm going the prerunner route rather than a street truck. I wanna be able to hit a curb doing 80mph and keep going! =^D I need about 10k to 15k worth of long travel suspension components though, and a few years to build it. I'm getting the engine for free off my step brother though, so thats a very good start to this crazy project of mine.
Respect no doubt bad ass built we are here in this car and truck game to do orginal things go fast have fun and love what we do if your gonna whine about fuel mileage then your in the wrong game when your building hotrods fuel means nothing and if you can't afford the gas then you shouldn't be building hotrods power is what its about and originally and fun I love what you did here keep up the good work man damn rite
Not sure if the engine is stock or not, but I'm pretty sure there are aluminum heads out there that'll fit the 8.1, not sure if Mark IV big block heads fit, maybe LSX heads if the LSX block is closer to the 8.1 block. Some aluminum heads and a cam to match would really wake it up and give it a wider rpm range if you'd ever like to wind it out. I think a n/a build would be sick.
please make a video comparing 7.4 v8 with 8.1 v8 their power differences and technical improvements! thank you I'm a fan of your channel and I love v8 I hope one day I can put one of these on my silverado here in Brazil.😎
I’m sure you know this but if you’re gonna turbo it, you can definitely reuse your stock bottom end, just add ring gap. Especially if that engine has like 100k plus miles of daily driving, everything’s happy and working together (rods, pistons, crank, etc) and can take quite a bit of punishment. For instance the 5.0 sbf I’m swapping into a ranger, the stock gt40p pistons and rotating assembly will take more power than the block will as long as the rings are gapped properly (shooting for 500 to the tire with a mild ish buildup and turbo) so I’m sure your 496 can take some lickin
im on the fence about it honestly (opening up the gap). I know its a good idea, but mainly because I do plan on building the engine to hold 1,000+ within the next year it would be 2x the work for a temporary short term solution... but we'll see what happens
@@LawrenceTolman well if you're going all out and have the budget, of course go with forged. But I know of a ton of stock bottom end engines holding ridiculous amounts of boost with just ring gap. A buddy of mine had a 351w from an 89 f250 with twins on 24 lbs making over 1000 on the stock bottom end and it held for a long time. Wasn't even the pistons that gave up in the end. Main bearing grabbed the crank at 6500rpm and thats all she wrote. Those junkyard motors can surprise ya lol
Iv got a stock 05 gmc sierra with a 5.3 and has 20 inch gmc wheels from a newer truck. My truck roasts the tires just fine and honestly from flat footing it does it better and has a better smoke show. Not sure what 5.3 you have lol. Love the look of the truck tho. I'd like to lower my truck since its a 2wd about like yours.
I think it's worth it it a unique build that most people can't say they have every one fan boys over the 5.3 and don't get me wrong it's an excellent engine but it's better to stand out in a world full of all the same
Somebody hasn’t been watching Richard Holdener’s channel on 5.3l’s 🤭 good project sir. I highly encourage you to check out the turbo stuff Richard does, it’s definitely awesome.
I've seen a bit of what he does, and sure, you/he can make a lot of HP with a 5.3, but the torque @ low RPM was what set the two apart for me, and also comparing NA to NA. I know folks have been begging him for a long time to do an 8.1, I would be excited to see that also
@@LawrenceTolman -very true 💁🏼♂️ I don’t own the 8.1l, but do have a 454 and mileage is so bad that it pushes me to think that a 5.3l with a whipple charger would be an acceptable comparison.
Can this conversion pass the California smog laws? And be smog legal? Its a great alternative that replacing stock 475,000 mile motor thats in my 04 silverado crew cab short box.
Be a good swap for my C30. The original TBI 454 is getting tired. Wish the accessory brackets were easier to find (for a squarebody you need the Workhorse brackets that put the A/C compressor up top)
For the money I would turbo the 5.3. But big blocks have a cool factor that can't be matched. One more thing. You blow up the 8.1 those aren't super easy to find. 5.3 on the other hand are everywhere for cheap. Stock 5.3 with a decent turbo setup then just swap in another 750 motor when she goes.
Great video LT!! I can attest to the struggles and finances involved in this awesome build you did. My 13’ Ram 1500 has 500miles on the 5.7L to 6.4L stroker motor now; it was expensive and very time consuming, I believe in the end it’s worth it. I will say all the bottom end torque is nice! Barely pushing the pedal is easy cruising. Mine is called “Red October” 4door 4X4 lowered 2/4.
Lawrence LT Tolman. Thanks! I know you are planing on going turbo, but I think it would be really cool to see a heads and cam combo; but with that low compression you are boost ready. Are you on Facebook/ Messenger, I’ll send you a video.
i like the idea of a turbo. it's funny you sound like me talking about my 6.0 only mine isn't doing donuts. aint tryin' either. it's got locker, 4:10 gears and better tires. high traction, similar alleged power, though not the torque and original parts.. something would prolly break. it'll turn them over though usually the wife aint thrilled if i do lol. i have got her sideways out of lights a couple times. it's also in a 3/4 ton 4wd frame. it did give a newer challenger r/t a run for it's money with all that weight. amazing engines.. i say that being a ford guy my whole life. just knew the ls was a really good one, got lucky on a deal with my brother inlaw and bought it.
Curious what to did to the harnesses. Was it plug and play or did you have to repin stuff? That wasn’t mentioned. But got me really curious I want a 8.1 or a 454 lol
I had a K2500 HD with an 8.1L mated to a 5 speed Allison. At best, I was able to achieve 11 mpg on the highway. I thought the power and torque was impressive until my dad proved his stock Duramax equipped truck would accelerate much faster and he was towing a 7500 pound camp trailer. That being said, get that turbo on your truck LT.
I hate being myself but, a 370 shortblock, with stock 5.3 706/862 heads, elgin 228/230 or 238/242 cam, PAC1218s, ebay long tubes, TBSS intake, ebay 102 TB, thinner cometic headgaskets in the 0.041"-0.027" range to up compression, 160 tstat, NGK TR6s and a Circle D or Yank 2800-3600 converter would rape that thing all day long on HP and I believe that it would also beat it on TQ. Depending on the cost of the 0.030" over 6L it could be cheaper, the same or onky slightly more than this 8.1 swap. The biggest question is how much boost can an 8.1 take? A gen IV 6L shortblock with gapped rings has made 1,500+hp for Richard Holdner maxing out a 3 bar map sensor and not breaking. Cool build, subbed, very interesting.
there's no question a 6.0 could make a lot of power with a good cam and some other mods, but honestly, this build wasn't/isn't about doing what everyone else has done. I want to try something out of the ordinary... Oh, and yeah, the stock 8.1 wont hold up a lot (if you believe the internet) so it will eventually get built and probably stroked out as well.
Its hard to find a 2500 with the 8.1 these days. it only shows me 22 trucks on autotrader (with 4wd selected). So next best thing would be getting a 2500 with a 6.0 and swapping it to an 8.1. However, I notice that it is also difficult to find a 8.1 engine and tranny combo for sale on ebay (or any other website)... Sucks, im graduating soon and will be getting employed right off the bat and would like to finally upgrade to a better truck. Always wanted an 8.1...
Let’s say you had a stock stall, 4l80e with say 3.13 gears or so for a daily driver 8.1 swap. Think that would get ok economy? Like at least 12 city 16 highway if you didn’t romp it? Always wanted a big block half ton
it might get a little better mileage, but with a 4l80 and those gears, it would be a dog out of the hole, and you'd be putting your foot into it a lot just to get moving (which uses a little more fuel).
I had a 2001 Sierra with the 6.0L V8 and 4L80e/4L85e. Was a stout truck and then the 6.0 wanted to blow. Had plans to swap a built 8.1L and a built Allison 6 speed but ended up having to lose the truck. Currently got a 94 F-150 that I plan to swap a BBF V8 and have an adapter housing made for the Ally 1000 with the SAE 2 or 3 bellhousing. I'm choosing a built Allison because why the heck not... The C4/C6 and TKO crap is SO OLD......So here's what I got in mind. -Built, Stroked and Sleeved 460/7.5 (stroked to 501/8.2) -MSD Direct Ignition -Jon Kaase HEMI heads -Built Allison 1000 6-Speed -Stand Alone TCM (Hoping I can set my shift points to 6400) -Sterling/Dana axle conversion -4.10 Gears
@@LawrenceTolman If the idea with the Allison goes wrong, I may be able to contact Performance Automatic OR Browell Bellhousings to see if they can make a bellhousing to fit on a chopped Ford 6R80 trans. I don't wanna give up on the 6-Speed auto conversion since I'd like to have a double overdrive on an old engine.
You won;t need to go to that high of an RPM with the Allison. I have a 8.1/Allison and the gear ratios are perfect. Just find the right rear end gear so as the transmission shifts through the gears it stays in the power band. On an 8.1 it's like 3600rpm, my 8300lb truck moves right out from a stop all the way up to 85(I don;t take it past that, it's a stock 2500HD not a race car) There really is no comparison to older transmissions or even the 4L80's, the Allison is a game changer and you can alter your entire build around it. It's like having a T56 that shifts itself, the ratios are just spaced right and are all pretty close.
Very cool, I love a sleeper. Did you know the Colorado SS single cab weighed only 3500?? You could put a stock ls7 in that and smoke a 2023 Camaro. I'm down for a muscle truck 💪
I used to own a 8.1, but gave it to my old man. He tells people it gets 18 mpg. 10 on the highway and 8 in town! 🤣
Lol! That's kinda how my truck is. Pass every damn thing on the road, except for the gas station!🤣😂lol
Best comment of 2020
Hahaha that’s a good one
That's about what mine gets. I can squeeze 10 in town but only if you drive like a grandpa
Hahaha
I'm with you LT, regardless if it was worth it or not. The fact that you can and you did the swap is just cool and honestly why not, right. I enjoy watching this build solely due to the fact that it is not a high end build that costs you your first born, and is totally achievable in your own garage.
it was kind of cool to do it at home with no exotic parts and more or less basic tools
This dude has the most soothing demeanor of any car channel I’ve ever seen
This guy seems like he would be a good mechanic for horse power tv or something.. he had that look and voice.
I think he would be good on the truck show...
He even has a TN license plate, Horsepower Tv is filmed in TN.
@@LawrenceTolman 😂😂🤘🏻🤘🏻 when you know you know 🤷🏼♂️😂
@@LawrenceTolman LOL they don't know....
@@LawrenceTolman you are for sure better than the guys on there now. I know I am a master mechanic watching a show for normal people but, dang they play up the tiniest thing.
Keep 'em coming LT. Not a truck guy, but like how you talk through and show one of the most overlooked parts of a swap...the dang wiring harness.
thanks! i try and show every step along the way
Best part of all this is you are bringing to light an engine offered by GM that not many people know about! Keep at it!
thanks! i do like the more obscure and off the beaten path stuff
4:27 does a killer burnout & in the same breath, “ I can’t figure out for the life of me why this truck is wearing out rear tires!”
Guy fukken rocks! 👍😎
I think it's pretty cool that LT takes the time to read and reply to so many comments. Also, he doesn't get defensive and blast a bunch ppl taking up for the 5.3l. Obviously 5.3's are cheap and awesome, no better bang for the buck, etc. This 8.1l swap is super cool and waaay more unique.
> 1L of displacement per cylinder. Imagine if it was a single cab.
Done a few single cabs...
Imagine that 8.1 in a single cab s10 or colorado. Would have a real hard time keeping the tires planted
I’ve always sorta-kinda wanted to build a short box standard cab 2WD ‘SS 496’ (throwback to the ‘90s 454 SS trucks) half-ton Silverado with the 8.1L drivetrain. Of course it’d be black, with custom decals in the same font and everything as the old 454 SS trucks, I think it’d be cool. I figure the 8.1 with just an intake, headers, exhaust, and a tune should be kinda a rocket with stock reliability forever, vs. building a 5.3. No way would it fit in my Colorado, though, and it’s genuinely fast with a factory 5.3 and factory 4.10 gears.
@@ejmarkle60 yc0 77789inches hide 0zfzup
JE as47 was
i just did a mk4 454 in my single cab 91 , with an open diff lmao about the same hp level (holley sniper ,long runner intake and long tube headers)
I have a Yukon XL 2500 8.1 with 4.11 gears. Aftermarket tune, catback exhaust and new high flow cats. I just did a 300 mile round trip and got just a tick over 12mpg, premium. Still totally worth it. This engine is a gas diesel. So much torque available right off of idle.
You are the Richard Holdener of truck building. Keep up the good work!
well thank you! those are some big shoes to fill...
I've seen a couple of your videos before, but after watching this one I swear that we live close to each other.
possible, I'm on the west side of Utah lake
@@LawrenceTolman I'm about 15 minutes north of you then.
Smiles per gallon out of that 8.1 and thats what matters. Can't wait for the next phase.
plenty of smiles driving it
I have an 01 2500hd with the 8.1/allison combo. Upgraded form a 1/2 5.3 Towing is night and day. I can tow 8k and the 8.1 rarely if ever comes out of overdrive. Loads of torque. When it downshifts towing it only runs about 2900 rpms. I love it. Only problem I haven't figured out is how to drag a gas station behind me yet. 10 mpg town/hwy.
yeah, they're thirsty
Need to do a torque per dollar comparison, that truck is bad ass.
that would be a good idea
A 8.1/transmission and everything else that goes to the engine can be had for under 4k
8.1 is very reliable and easy to maintain. Mpg not great but when comparing I bought my 04 hd2500 almost 6 years ago with 40k for 23500$ shipped to my front door all fees included (1500$) shipping. Oregon to Texas. The same truck with dmax at time was at least 10k more plus ttl here. I love it. Had to put fuel pump on it because of how it was stored prior to purchase. But only valve cover gaskets since. 140k now. No regrets. I have 33s allison and recently 4.56 gears. Still 10 mpg combined driving. Sorry so long just wanted to inform non owners. Myself and 3 friends all daily 8.1s. Mine is lowest miles. One friend over 300k never out of truck only gaskets, plugs, wires.
they are very reliable from what I've read and heard
Thank you for making these videos! There is not much content covering the 8.1. These are such badass engines. I drove a UPS truck with 8.1 Allison combo, it took a beating every day for years. I have an 8.1 suburban and really looking forward to seeing what you do with ugly truck.
I think 14-15 mpg is a bit optimistic, even with overdrive. The 8.1's were notorious gas guzzlers when new. 3000 rpm at highway speed is pretty high IMO.
However, as a fun, joy ride type toy, it's a great ride!
Also, great production quality in this video. Very well done. Reminded me of a episode of Stacey David's Trucks show. 👍
Also love that you ran the numbers and said what you paid. Love it!! Thanks for this series
I’d love to have off road truck with an 8.1 and Allison.
bulletproof combination
I always wondered about those 8.1’s, glad you chose it
It’s a cool platform
@@LawrenceTolman I just came about an 8.1 that came out of a boat. Which is already cam'd. This makes me want to put it in my 2000 chevy really bad.
@@danking5382 do you have any of the marinizing parts for sale. if so let me know
This thing would be a monster even with LOW boost!
gonna limit it to 5-6 pounds probably until I build the bottom end. they say 550hp or so is the limit for the stock pistons
Would love to see you focus on making more N/A power before you boost it. But either way I’m still gonna watch it!
@@LawrenceTolman i'd do it all at once. the ring gap and compression might be an issue. maybe a cam to work work with the turbo would be wise though i don't think that would be needed to just get it going. the stock valve springs and rockers might need to be addressed to. the springs are weak, and bearings give out if you get too crazy on ls engines. it sounds like you might though i know the 8.1 is a bigger block and i think it's not actually a "ls engine". i love the idea of a sleeper btw awesome idea. got ideas for my little ranger.. was thinking a 302 built up but not sure. that ls in 3/4 ton is nice and anything in that family with a cam..
@@blueovalfan23 The Vortec 8100/496 is not an LS.. That'de be wishful thinking.. Hahaa
@@blueovalfan23 weak stock bottom end cant take much boost
Love ya LT! Been watchin you since you first started on PB. Definitely have matured and are more comfortable as a video host. Keep up with it, looking for more Truck Tech.
I appreciate that! It was a learning curve for sure
I've always wanted someone to do this... Glad to see you knocked it out
it was fun! and not that hard of a swap either
@@LawrenceTolman I'm gonna have to look into it.
And not to forget: worthy acoustics, finally 😉
I knew someone here in California that had one of those 8.1s in a long bed dually and he put a Gear Venders Overdrive box behind the Allison and towed triple axle horse trailers in the winter and new 5th Wheel RVs all summer and last I heard there was over 600,000 miles on the stock drivetrain.
Other than the usual alternator, waterpump, and fuel pump here and there the only issues were intake gaskets (twice),plastic intake manifold (once),crankshaft sensor(twice), rear main seal and the high pressure line on the hydoboost system(both at once) but with that Allison/GearVenders combo he was getting decent fuel mileage and only replaced the brake pads once about every 80,000 miles!!!!!
You should do the same thing, but with a Quadraster truck, That'd be pretty sweet.
ive never even driven a quadrasteer rig, i think that would be pretty cool
Amazing! I always thought that 8.1 was the one people hated. I'd like to see this engine in a GMT400 model.
a lot of people favor the LS for parts availability and weight savings, but the big block still has a small following
Yeah people hate them cause you can't throw a bigger turbo on them and dump a bunch of black smoke out the back like a Duramax or a Cummins. They might have more fans if they were optional in half tons, but gas big block heavy duty trucks, that really hasn't been a popular thing since the 80's/early 90's, the Dodge Cummins pretty much changed the world 30 years ago away from gas engines in heavy duty pickups.
Hopefully you figure out what’s making those rear tires wear like that. Keep us updated 😂😂😂
I hope so too!
@@LawrenceTolman Check your tire clearance, I’ve seen a tire Spaghetti like that it was because the tire was rubbing against the wheel well when accelerating/or carrying to much weight.
Judging from this video I could take a pretty good guess.
I can’t wait for more vids on this build!
making some more as we speak
Great truck mod and what a interesting swap to a big block. Looking forward to future mods. Your knowledge from HP tv is a added bonus. Thanks for sharing. Fan from Sydney Nova Scotia
Thanks for watching! Yes, have learned a lot from them
I am absolutely in love with the 8.1
they are such a fun engine
ive got an 8.1 in a 2004 gmc wrecker i have, and when i am done with the wrecker, that 8.1 is going into my 1970 cadillac deville convertable for sure
Like your videos, but your 14 to 15 mpg estimate seems optimistic, particularly with the gearing
It's a good bang for the buck truck. I'm closer to $5K on my swap, but I changed the transmission, had to source brackets for the Squarebody swap, and did headers and a segment swap on the PCM for the 4l80e. But....Big Block! For comparison, you cannot get into an 8.1 2500HD even with 200k+ miles for under $12k, and....Big Block.
Ah, the peeling clear coat on the hood and roof is an all to familiar sight lol but I'm starting to think my 02 Silverado might be the "uglier truck" :(
yup, classic GM paint
And I thought only the white gm paint only peels lol
Well, I hope my 5.3L never needs replacing, but if it does, this confirmed my decision to drop an 8.1L in. My worries then are the 4L60E and G80 diff in the rear😆
it would do a number on the stock trans for sure
I can tell you from experience that truck would be more fun and feel faster with a much higher rear gear. As in 3.08s or 3.55s. With 3.08s it would feel like a rocket ship on the highway and still have plenty out of the hole on street tires. Very low gears in a truck like that would only be useful if pulling a heavy load like a large camper or towing a race car. Low gears are also great for smaller high reving engines
This is a great swap. Thanks for the info and detailing the minor issues with it. Great channel
Thanks for watching!
Loving this series! Keep up the good work, you clearly know what you're doing.
I own a 2001 Sierra ext cab 5.3. I recently just added 2inch lowering shackles and it got rid of the infamous GM rake. I'm digging the 4/6 drop on yours!
I'm probably not gonna turbo mine but will put a stronger trans, camming it, and perhaps swapping gears in the rear end. Thanks for the inspiration!
sure thing!
I did a 5.3 to 6.0 with h/c/I in my 1500 silverado. I haven't gotten it dynoed so I cant say what power it makes. But after seeing your videos, if I could do it again I'd 8.1 swap it, dont get my wrong. The 6.0 is great and fun but 496 is just so much cooler. And I can tell you I have wayyyy more then $3000 total into everything in my truck so the 8.1 swap seems to be alot better of a budget build. Not to mention depending on your area or what kind of deal you can find changes the price. My 6.0 in the same situation as your 8.1 was only $1350
This is a super sick swap, and def one of a kind. I'm gonna sub just for the turbo big block content in the future, I mean who could say no to that?
I know, right?
410s -430s is good, 3200 stall, cam. All it need lolol hell I do 2700 rpm in my 454 slammed obs crewcab with 410s with a 4l80e. Long trip I can do 300 on a tank. But city highway I do about 240 per tank. About 16-17mpg combined ill never sell mine... love the swap and truck man!! Stay different !
glad someone out there understands!
I love how you tell me what I need ti know without getting into friendship zone... that comes later
A budget pump gas upgrade for most of your towing duties. Makes sense to me.
I have a 2001 2500 hd 4x4 with a 8.1 and I get 14 on the highway and 12 in town it has a 4.10 gears on 35 x12.5 x 22s
not bad at all for a big block on a heavier 4x4
I'd love to put an 8.1 in my 96 Buick Roadmaster sedan. The LT1 does okay, but it really needs a lot more. I only get 12-16 MPG anyway, so I might as well have a bigger engine
you should!
For me the biggest issue with the 8.1 is the lack of aftermarket support.
yeah, its certainly not as well supported as the LS world
@@LawrenceTolman going off of what William stated, you should do a segment on what kind of aftermarket support there is for this engine. Would be good information to know.
Plus aftermarket parts r expensive $$$ for 8.1 which is basically a bbc with ls electronics..
That is just a cool truck right there. The turbo build is gonna be great. Can't wait to see how it goes
I have an 04 with an 8.1 and 4.10 gears and love it. I pull a 32ft camper and my boat with it and it's an excellent tow rig. The mpg sucks but I also have never needed to fork out thousands of dollars (just for parts mind you) to replace head gaskets or injectors on a Duramax. That motor is extremely reliable, Mercruiser offered the package for boats and I remember reading that they tested the 496 at wide open throttle for 500 continuous hours and it held together. That being said someday I'm still going to sell my truck to my dad once I find a clean low mileage cat eye Duramax with no rust 😂 I look forward to this build!
no question, a diesel is superior for towing a lot, but they are a lot more expensive to purchase and maintain, so a big block is a good substitute.
Also I have 4x4, crew cab, steel flat bed, full front end replacement. 8100 lbs empty.
Best looking truck for its year
There are a lot of ways to get those numbers from a 5.3 to start.. but the difference will come later with add on’s as the bar is raised, so will the separation from the two.
got that right
Imagine a T56 behind it! Now that’d be fun
It would be
For sure;)
I stumbled across a company called Raylar Engineering in my research of this very same swap for my 03 Silverado that actually makes what appears to be good parts for these 8.1 Vortecs, forged stroker cranks and aluminum cnc ported heads could make that a whole lot more fun
Yeah, I’ve seen a ton of their parts and hope to get some when I build the engine
That 8.1L Vortec in that Silverado is a beast LT.
thanks! its a blast to drive
@@LawrenceTolman You're welcome LT. Are you planning on adding aluminum heads to the 8.1L Vortec as well.
I've been really interested in this swap thanks you've opened my eyes so much
I had a 02 Avalanche 2500 4x4 with the 8.1l it was 373 geared and I had folks with 6.0 and 6.2 trucks ask me what in the hell do you have under that hood we cant keep up!...so yes the 8.1l is a total different ball game!..mabe a game changer!
I have an old carburated 460 big block out of an 80's E-350 RV I want to stuff into my ugly 2002 F150 once I kill off the bone stock 4.6 modular that's currently in it. After the engine swap I want to cage and back half it. I'm going the prerunner route rather than a street truck. I wanna be able to hit a curb doing 80mph and keep going! =^D
I need about 10k to 15k worth of long travel suspension components though, and a few years to build it. I'm getting the engine for free off my step brother though, so thats a very good start to this crazy project of mine.
Respect no doubt bad ass built we are here in this car and truck game to do orginal things go fast have fun and love what we do if your gonna whine about fuel mileage then your in the wrong game when your building hotrods fuel means nothing and if you can't afford the gas then you shouldn't be building hotrods power is what its about and originally and fun I love what you did here keep up the good work man damn rite
thanks! its a fun truck to drive, regardless of the fuel lol... and tires
Subscribed LT! NOW LET'S SEE SOME TWINSIES IN THAT BAD BOY! ALWAYS WONDERED ABOUT THESE BBC ENGINES AND CAN'T WAIT TO SEE WHAT YOU DO NEXT!
thanks for the sub! working on turbo stuff this week, should have an upload soon
That looks so much better! Keep the paint!
I have almost zero paint and body skills so thats the plan haha
Been looking for one of the Suburbans with these in good shape.
Subscribed and following this build.
thanks!
LT would be interesting to measure before and after with a loaded trailer between mile markers measured distance.
that would be cool
Not sure if the engine is stock or not, but I'm pretty sure there are aluminum heads out there that'll fit the 8.1, not sure if Mark IV big block heads fit, maybe LSX heads if the LSX block is closer to the 8.1 block. Some aluminum heads and a cam to match would really wake it up and give it a wider rpm range if you'd ever like to wind it out. I think a n/a build would be sick.
yeah, a company called Raylar Engineering specializes in 8.1 stuff, and they have heads, cams, stroker kits, and more
As good or better then powerblock tv!! I'm used to hearing you speak I love it
please make a video comparing 7.4 v8 with 8.1 v8 their power differences and technical improvements! thank you I'm a fan of your channel and I love v8 I hope one day I can put one of these on my silverado here in Brazil.😎
I’m sure you know this but if you’re gonna turbo it, you can definitely reuse your stock bottom end, just add ring gap. Especially if that engine has like 100k plus miles of daily driving, everything’s happy and working together (rods, pistons, crank, etc) and can take quite a bit of punishment. For instance the 5.0 sbf I’m swapping into a ranger, the stock gt40p pistons and rotating assembly will take more power than the block will as long as the rings are gapped properly (shooting for 500 to the tire with a mild ish buildup and turbo) so I’m sure your 496 can take some lickin
im on the fence about it honestly (opening up the gap). I know its a good idea, but mainly because I do plan on building the engine to hold 1,000+ within the next year it would be 2x the work for a temporary short term solution... but we'll see what happens
@@LawrenceTolman well if you're going all out and have the budget, of course go with forged. But I know of a ton of stock bottom end engines holding ridiculous amounts of boost with just ring gap. A buddy of mine had a 351w from an 89 f250 with twins on 24 lbs making over 1000 on the stock bottom end and it held for a long time. Wasn't even the pistons that gave up in the end. Main bearing grabbed the crank at 6500rpm and thats all she wrote. Those junkyard motors can surprise ya lol
Those late model Z71 wheels look great with the red brake calipers.
Iv got a stock 05 gmc sierra with a 5.3 and has 20 inch gmc wheels from a newer truck. My truck roasts the tires just fine and honestly from flat footing it does it better and has a better smoke show. Not sure what 5.3 you have lol.
Love the look of the truck tho. I'd like to lower my truck since its a 2wd about like yours.
sounds like a badass truck!
I’m glad this came across my feed!!
Liked and subscribed!! I like this kinda stuff!
Awesome! Thank you!
@@LawrenceTolman I would like to know average MPG though
“14-15 mpg” is better than my 5.3 the way I drive it
One of my favorite gm truck body styles. Sounds pretty good too. I bet you like wearing those rear tires out. ;)
I am! although now I gotta buy some new ones lol
I think it's worth it it a unique build that most people can't say they have every one fan boys over the 5.3 and don't get me wrong it's an excellent engine but it's better to stand out in a world full of all the same
Gen 6 Big Block is closer to 4.8-6.0 in layout than previous gens.
lots of similarities in the design
ive built the same truck, just working out the wiring bugs, cost me a lot more because i built the engine and swapped in a bigger trans.
theyre a lot of fun!
Somebody hasn’t been watching Richard Holdener’s channel on 5.3l’s 🤭 good project sir. I highly encourage you to check out the turbo stuff Richard does, it’s definitely awesome.
I've seen a bit of what he does, and sure, you/he can make a lot of HP with a 5.3, but the torque @ low RPM was what set the two apart for me, and also comparing NA to NA. I know folks have been begging him for a long time to do an 8.1, I would be excited to see that also
@@LawrenceTolman -very true 💁🏼♂️ I don’t own the 8.1l, but do have a 454 and mileage is so bad that it pushes me to think that a 5.3l with a whipple charger would be an acceptable comparison.
I love truck tech on PN but i think i'd probably might stay here.
welcome aboard! and thanks for watching!
Why go with the 4.30 gears?
Shout out from Arizona 😎 keep up the good work. Just subscribed.
Awesome! Thank you!
Best part is the torque and the bbc sound!.
yup!
Can this conversion pass the California smog laws? And be smog legal? Its a great alternative that replacing stock 475,000 mile motor thats in my 04 silverado crew cab short box.
4.30 gear with an 8.1 is not smart. Why didn’t you put a 3300 rpm stall tc in there too?
How’s that? Most big block trucks with the 4l80 (the trans I have) come stock with 4.10s, so 4.30 is very close to that.
@@LawrenceTolman Those trucks are heavier, have taller tires and they are design to tow 10k+ pounds.
Be a good swap for my C30. The original TBI 454 is getting tired. Wish the accessory brackets were easier to find (for a squarebody you need the Workhorse brackets that put the A/C compressor up top)
yeah, they will be harder to come by. I saw someone on a FB group for 8.1 has brackets they make for the swap I think...
For the money I would turbo the 5.3. But big blocks have a cool factor that can't be matched. One more thing. You blow up the 8.1 those aren't super easy to find. 5.3 on the other hand are everywhere for cheap. Stock 5.3 with a decent turbo setup then just swap in another 750 motor when she goes.
you are correct on all counts, and thats why I'm gonna be super careful with the 8.1 before I build the bottom end
Great video LT!! I can attest to the struggles and finances involved in this awesome build you did.
My 13’ Ram 1500 has 500miles on the 5.7L to 6.4L stroker motor now; it was expensive and very time consuming, I believe in the end it’s worth it.
I will say all the bottom end torque is nice! Barely pushing the pedal is easy cruising.
Mine is called “Red October” 4door 4X4 lowered 2/4.
sounds like a badass truck!
Lawrence LT Tolman. Thanks! I know you are planing on going turbo, but I think it would be really cool to see a heads and cam combo; but with that low compression you are boost ready.
Are you on Facebook/ Messenger, I’ll send you a video.
i like the idea of a turbo. it's funny you sound like me talking about my 6.0 only mine isn't doing donuts. aint tryin' either. it's got locker, 4:10 gears and better tires. high traction, similar alleged power, though not the torque and original parts.. something would prolly break. it'll turn them over though usually the wife aint thrilled if i do lol. i have got her sideways out of lights a couple times. it's also in a 3/4 ton 4wd frame. it did give a newer challenger r/t a run for it's money with all that weight. amazing engines.. i say that being a ford guy my whole life. just knew the ls was a really good one, got lucky on a deal with my brother inlaw and bought it.
the 6.0s are great engines, and the HD drivetrain is nearly bulletproof... nice trucks
Curious what to did to the harnesses. Was it plug and play or did you have to repin stuff? That wasn’t mentioned. But got me really curious I want a 8.1 or a 454 lol
I had a K2500 HD with an 8.1L mated to a 5 speed Allison. At best, I was able to achieve 11 mpg on the highway. I thought the power and torque was impressive until my dad proved his stock Duramax equipped truck would accelerate much faster and he was towing a 7500 pound camp trailer. That being said, get that turbo on your truck LT.
yeah, I've got the L5P to handle the towing duties and it is impressive for sure
I hate being myself but, a 370 shortblock, with stock 5.3 706/862 heads, elgin 228/230 or 238/242 cam, PAC1218s, ebay long tubes, TBSS intake, ebay 102 TB, thinner cometic headgaskets in the 0.041"-0.027" range to up compression, 160 tstat, NGK TR6s and a Circle D or Yank 2800-3600 converter would rape that thing all day long on HP and I believe that it would also beat it on TQ. Depending on the cost of the 0.030" over 6L it could be cheaper, the same or onky slightly more than this 8.1 swap. The biggest question is how much boost can an 8.1 take? A gen IV 6L shortblock with gapped rings has made 1,500+hp for Richard Holdner maxing out a 3 bar map sensor and not breaking. Cool build, subbed, very interesting.
there's no question a 6.0 could make a lot of power with a good cam and some other mods, but honestly, this build wasn't/isn't about doing what everyone else has done. I want to try something out of the ordinary... Oh, and yeah, the stock 8.1 wont hold up a lot (if you believe the internet) so it will eventually get built and probably stroked out as well.
When ya swapped the PCM from black box to 0411 did the key fob to open the doors still work along with the AC, and the 4x4?
Its hard to find a 2500 with the 8.1 these days. it only shows me 22 trucks on autotrader (with 4wd selected). So next best thing would be getting a 2500 with a 6.0 and swapping it to an 8.1. However, I notice that it is also difficult to find a 8.1 engine and tranny combo for sale on ebay (or any other website)... Sucks, im graduating soon and will be getting employed right off the bat and would like to finally upgrade to a better truck. Always wanted an 8.1...
I would love to see other NA mods, before you add boost - either way super cool
i would love too, but turbo kit is already in the works
Lawrence LT Tolman save it for after - wink wink
11 mpg I own one, power is great
Let’s say you had a stock stall, 4l80e with say 3.13 gears or so for a daily driver 8.1 swap. Think that would get ok economy? Like at least 12 city 16 highway if you didn’t romp it? Always wanted a big block half ton
it might get a little better mileage, but with a 4l80 and those gears, it would be a dog out of the hole, and you'd be putting your foot into it a lot just to get moving (which uses a little more fuel).
I had a 2001 Sierra with the 6.0L V8 and 4L80e/4L85e. Was a stout truck and then the 6.0 wanted to blow. Had plans to swap a built 8.1L and a built Allison 6 speed but ended up having to lose the truck. Currently got a 94 F-150 that I plan to swap a BBF V8 and have an adapter housing made for the Ally 1000 with the SAE 2 or 3 bellhousing. I'm choosing a built Allison because why the heck not... The C4/C6 and TKO crap is SO OLD......So here's what I got in mind.
-Built, Stroked and Sleeved 460/7.5 (stroked to 501/8.2)
-MSD Direct Ignition
-Jon Kaase HEMI heads
-Built Allison 1000 6-Speed
-Stand Alone TCM (Hoping I can set my shift points to 6400)
-Sterling/Dana axle conversion
-4.10 Gears
sounds like a fun build! I have heard the allison has trouble shifting at higher RPM, but no firsthand experience with that.
@@LawrenceTolman If the idea with the Allison goes wrong, I may be able to contact Performance Automatic OR Browell Bellhousings to see if they can make a bellhousing to fit on a chopped Ford 6R80 trans. I don't wanna give up on the 6-Speed auto conversion since I'd like to have a double overdrive on an old engine.
You won;t need to go to that high of an RPM with the Allison. I have a 8.1/Allison and the gear ratios are perfect. Just find the right rear end gear so as the transmission shifts through the gears it stays in the power band. On an 8.1 it's like 3600rpm, my 8300lb truck moves right out from a stop all the way up to 85(I don;t take it past that, it's a stock 2500HD not a race car)
There really is no comparison to older transmissions or even the 4L80's, the Allison is a game changer and you can alter your entire build around it. It's like having a T56 that shifts itself, the ratios are just spaced right and are all pretty close.
Very cool, I love a sleeper. Did you know the Colorado SS single cab weighed only 3500?? You could put a stock ls7 in that and smoke a 2023 Camaro. I'm down for a muscle truck 💪
you can call jegs and get an atk 6.0 remanufactured long block rated at 460 hp with warranty for 3900
theres no question an LS can be cheap and powerful
3900?!! Are you out of ur mind. You could build 2 6.0 engines for that price
Can’t wait here it with some headers!!
i cant wait to hear it with a turbo
This a damn good video. I subscribed. Keep up the great work!
thanks!
It's an awesome truck LT the old saying there is no replacement for displacement holds true cubes are king.
Agreed!