Anyone own a vehicle with this engine? Eats gas of course, but is there anything inherently bad with this engine?
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Gm Vortec 8.1L?
- Thread starter RedVenom48
- Start date
Ive looked into these engines as well. Seem pretty well built. Look at raylar engineering. They carry superchargers and stroker kits for these. I've been considering putting one of these in a 69 gmc i have, among other engine opinions im considering
Sent from my SM-G965U using the svtperformance.com mobile app
Sent from my SM-G965U using the svtperformance.com mobile app
I asked my Chevy buddy about one of them once, him and his dad were doing an 8.1 swap into an H2 for a guy and I asked why not build the 6.0 instead. Neither of them understood it either, and neither of them really liked those engines, parts were a lot more expensive. This was like 8 years ago though so I have no clue if that's still the case.
Had a friend who had one in an avalanche. Think he went over 200k easily and I know he wasn't a maintenance freak with that truck
Lasted him a long time before he went for diesel truck.
Lasted him a long time before he went for diesel truck.
It's an updated big block based on BBC architecture, not LS architecture.
Cylinder heads are not bad but the exhaust manifold studs are small (M8x1.25) and break often. I was always replacing them on a 3/4 2005 Suburban i had years back.
TBH, i wasn't real impressed with the power that truck made.
Cylinder heads are not bad but the exhaust manifold studs are small (M8x1.25) and break often. I was always replacing them on a 3/4 2005 Suburban i had years back.
TBH, i wasn't real impressed with the power that truck made.
I have a friend with a 8100 Sierra 2500 and he loves it, hasn't given him any trouble either as far as I'm aware.
My mom's husband was part of a race team that had one in a 3500 Dually. He said it never gave them any issues even when towing the 30+' race trailer. Well, aside from never being able to pass a gas station.
It's a good engine, makes decent power, and is fairly cheap. The aftermarket for it is tiny and shrinking since it has been out of production for years. Basically nothing from earlier BBCs will work with the 8100. If you were just doing a mild build I'd rather start with a Vortec 454. Tons of aftermarket support there. I know a place to get good mildly used ones at a decent price if you're interested.
We service one in a Yukon XL. It’s been relatively minor maintenance over the years. Most likely due to being elderly owned. Only real issue we have with this particular variant; it doesn’t like A/C compressors. I will say it’s relatively stock, cat delete only, and that thing has a lot more ass behind it than my 5.3.
Pick your poison.
Pick your poison.
Thanks for the replies all.
So, Im looking at this engine as an option in the next truck I purchase. The Excursion has too many gremlins piling up and frankly, I have no desire to put more money into it. The Triton series of engines isnt bad, but I have zero desire to dive into them for major repairs. In this realm, the GM LS and this here 8.1 are superior.
I dont want a new truck payment, and I want something thats simple and reliable. Im open to a 2003-2006 5.9 Cummins Ram, but Ive only found a handful of them.
So, Im looking at this engine as an option in the next truck I purchase. The Excursion has too many gremlins piling up and frankly, I have no desire to put more money into it. The Triton series of engines isnt bad, but I have zero desire to dive into them for major repairs. In this realm, the GM LS and this here 8.1 are superior.
I dont want a new truck payment, and I want something thats simple and reliable. Im open to a 2003-2006 5.9 Cummins Ram, but Ive only found a handful of them.
I have an 02 in a 2500 HD. Its clapped out beyond belief, and gets thoroughly abused in farming operations. Got 10.1 the first tank I owned it, and thought screw it, and drive the piss out of it and don't get much less than that. It has CEL for knock sensor and something else, but it still starts so I don't worry too much about it. Oil get changed when its convenient, and we just use 5w40 from our bulk diesel container. It has 262k miles and I assume the seat will fall out the rusted bottom before the engine quits.
Bite the bullet and pay a little more for the Cummins. Fuel mileage alone will be roughly twice what you’d get with the 8.1 and while there are a few irritating things with the Ram, they’re relatively easy and inexpensive to correct.
03-05 will they make all the power you’d need with HPtuners and don’t have nearly the electrical gremlins. If you want to go wild on mods the 06-07 are where you want to be to use EFILive though you have the TIPM which is a double edged sword.
The 48re is a badass trans when built but doesn’t have that nice OD spread like 5th in the Allison though for towing but it will still pulls awesome with that low end torque.
I have a 2004 GMC Sierra 2500 HD with the 8.1L and the Allison 5 Speed auto. I got the truck in 2013 with 91K on it and it now has 118K. The trucks is a beast. I only plow the driveway, go to the dump, and tow my car with it, hence it's low mileage. The truck tows my 20' trailer with my hellcat on it with no issues. It's stock besides shorty headers, intake and catback. They like to drink oil. Between oil changes I usually put a quart of oil in it, but that's pretty common from what I've read. It's a shame they don't offer a motor like this anymore.
Word is that GM is working on another BB.
That's a good looking truck, Ray. 27K miles over the past 8 years is definitely low miles. I assume it's primary duty is to tow your Hellcat.
I just bought an immaculate 01 2500HD 8.1. My two checked fill-ups got me 12.5mpg. 3.73 gears. Keep in mind the factory tire was 245/75/16. Even a 265/75/16 is going to throw your mileage/economy off - 5%.
They have oil consumption issues because of the intake manifold design and how oil vapor is sucked in. Supposedly the best fix is a lower thermostat.
The Allison trans in the truck is really nice. I wouldn't want to own an 8.1 behind a 4l80 with that sucky long first gear, which is what every 2500 suburban/Yukon used. Probably why they seem to have worse fuel economy.
I had a same year 6.0 2500 and it felt slow to me from a dig. The 8.1 roasts tires.
They have oil consumption issues because of the intake manifold design and how oil vapor is sucked in. Supposedly the best fix is a lower thermostat.
The Allison trans in the truck is really nice. I wouldn't want to own an 8.1 behind a 4l80 with that sucky long first gear, which is what every 2500 suburban/Yukon used. Probably why they seem to have worse fuel economy.
I had a same year 6.0 2500 and it felt slow to me from a dig. The 8.1 roasts tires.
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Is that 12.5 your average city/highway? If so, thats already a 3.5 average improvement over my Excursions V10 lol.
More a mix of highway and rural with some around town. But all shorter trips. None longer than 18 miles. Same gas pump each fill-up shouldn't be any bad math in there.
Bet city driving would tank the mileage quick.
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Also, truck was old enough that I Classic tagged it. No annual registration. Cheaper insurance.
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