454 tbi with 4l85E swap into c1500 350tbi

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PlayingWithTBI

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That's the difference between the "antique " and "classic " plates, right? The mileage restrictions?
AZ only does Historic Plates. The mileage restrictions have nothing to do with them, they don't care. It's up to the insurance company. Once your insurance reports to MVD (yes it's MVD in AZ, ha ha) you have that type of policy, MVD will exempt you. Otherwise any vehicle built later than 67, has to have emissions here in Maricopa County, ugh.
 

Supercharged111

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The 8.1 liter gen 6 big block is very interesting from a tech standpoint, as it is essentially a stroker 454 to 496 set up like a LS motor. It has the 7-4 firing order swap, cathedral port heads, and individual ignition coils. Raylar and Dart both offer aftermarket heads for them. Several companies offer camshafts for them and they are torque beasts. I would love to play with one in my hauler rig, just because I can. They are starting to get harder to find. Oh and don't even try to run a 4L80 behind one. Allison 6 speed only. I wish someone would offer a legal manifold for them, aside from Raylar boring out the stock manifold.

I'm gonna have to go ahead and disagree with the 4L80 statement. I'm pretty sure my 454 punches harder than a stock 8.1. I know the blower has been on the truck for just shy of 100,000 miles, but it's likely you can add another 20,000 or more to that number. Original trans as far as I could see. Smelled like original fluid when I flushed it back in March. I haven't even shift kitted the thing and put a 5,000# camper in the bed and a 9,000# trailer out back. Prior to my ownership, it saw 80,000 miles with a 2500# welding bed on it and frequently towed in that configuration. I don't think you're giving the trans enough credit. It would be an easy enough swap though for my truck with the TCM-2650 I believe it's called. But the reality is that, even if I do gut the trans, I'll likely just rebuild with stronger clutches, shift kit, etc.
 

someotherguy

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There's GMT800 dudes making serious power, drag racing boosted LS's and 4L80E is the way they go. 'nuff said :D You won't be finding any Allisons in that bunch. A few are running 6L80E's but apparently the tuning is a lot trickier.

Richard
 

Bloodwater79

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Bloodwater man I am SO SORRY we have totally hijacked your thread. Please pop back in here and keep us posted on your swap project. Don't let anyone discourage you; if you have even half-ass mechanical skills and ambition, your swap is totally do-able without major hassle. Yeah you'll need to source/make a few supporting items but so far the biggest hurdle I see is that 3500HD transmission; if you can spring for a rebuild then the shop can change out the tailshaft and housing from one of their core units, or you could source a non-HD trans elsewhere.

Just as motivation this was a former '94 3500HD 6.5TD/NV4500 that was missing the engine, trans was junk, interior was trash, and pretty much every body panel was shot. I did a Vortec 7.4 swap, full 95-up interior swap, and built the truck almost literally the way the factory would have - using "spare parts" from donor trucks including 93, 94, 95, 96, 98, and 99 and in my "spare time" ... :D

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Richard
lol...not a problem, I was actually out of town for the last several days and stayed away from the internet. took the family camping so no new progress on the truck.
 

Bloodwater79

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Some of us have actually built trucks, from the ground up, so I wouldn't worry to much.. :D


I think the goal is to obtain something that wasn't available factory, or not easily available. OP sounds like he's building somewhat of a homemade 454SS with parts he has available due to the donor truck being rotted out. My project dream is something that never existed, a C1500 RCSB with the 8.1. :D Nice little hot rod made with a combination of factory parts.

Richard
My dream truck build that I have been talking about but have not started:
I want to find a 67-69 c10 and a similar year suburban
I want to cut the burban behind the 2nd row seats and turn it in to a crew cab, then mod the frame of the c10 and drop a duramax with either the 6 speed manual or allison into it and use it as my hauler. This way I can trailer my 69 camaro and have the excuse that I don't want to put miles on the new car :)
 

Bloodwater79

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Nice job on your update! When you did the interior update, how did you handle the wiring issues? I have a beautiful complete 97 interior to put into my 93 crewcab, but the harnesses are totally different at the firewall connection. I guess I can delete the air bag stuff, but then what. The 97 has the ECM on the fender whereas the 93 has it behind the dash. I wonder if maybe I need to find a dash harness from a 95. Thanks in advance.
I believe the 95 is the route to go, since it would be OBD1 and the 97 is OBD2. I had that issue when I was rebuilding a 93 Transam, the better parts were on teh 96 and 97 but the computer and wiring were different due to the change to OBD2
 

PlayingWithTBI

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95 was kind of an odd-ball year for PCMs and controls with OBD2 coming up, you may want to think about an earlier year on which to base your project.
 

stutaeng

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And the 4L80e did come mated to the 8.1 from the factory in the 2500 Suburbans and 2500/3500 Express Vans. Actually, the Express Duramax also had 4L80e.

I'm gonna have to go ahead and disagree with the 4L80 statement. I'm pretty sure my 454 punches harder than a stock 8.1. I know the blower has been on the truck for just shy of 100,000 miles, but it's likely you can add another 20,000 or more to that number. Original trans as far as I could see. Smelled like original fluid when I flushed it back in March. I haven't even shift kitted the thing and put a 5,000# camper in the bed and a 9,000# trailer out back. Prior to my ownership, it saw 80,000 miles with a 2500# welding bed on it and frequently towed in that configuration. I don't think you're giving the trans enough credit. It would be an easy enough swap though for my truck with the TCM-2650 I believe it's called. But the reality is that, even if I do gut the trans, I'll likely just rebuild with stronger clutches, shift kit, etc.
 

Christian Steffen

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I'm gonna have to go ahead and disagree with the 4L80 statement. I'm pretty sure my 454 punches harder than a stock 8.1. I know the blower has been on the truck for just shy of 100,000 miles, but it's likely you can add another 20,000 or more to that number. Original trans as far as I could see. Smelled like original fluid when I flushed it back in March. I haven't even shift kitted the thing and put a 5,000# camper in the bed and a 9,000# trailer out back. Prior to my ownership, it saw 80,000 miles with a 2500# welding bed on it and frequently towed in that configuration. I don't think you're giving the trans enough credit. It would be an easy enough swap though for my truck with the TCM-2650 I believe it's called. But the reality is that, even if I do gut the trans, I'll likely just rebuild with stronger clutches, shift kit, etc.

4l80e is definitely stout enough for a normal NA 8.1, I'd almost say most NA 8.1s.

I do think that the 8.1s are cool. IMO though if anyone wants to mod them more than just a cam swap it might be more beneficial to just start with a L29, turn it into a 496, and throw some really good heads at it and a good intake manifold.

There's GMT800 dudes making serious power, drag racing boosted LS's and 4L80E is the way they go. 'nuff said :D You won't be finding any Allisons in that bunch. A few are running 6L80E's but apparently the tuning is a lot trickier.

Richard

The tuning for the 2014+ 6l80e is definitely complex, I can vouch for that lol from what I've read they're quite strong when tuned correctly, even stock. Apparently a bad tune can kill them though.
 

Sam Cooper

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There's GMT800 dudes making serious power, drag racing boosted LS's and 4L80E is the way they go. 'nuff said :D You won't be finding any Allisons in that bunch. A few are running 6L80E's but apparently the tuning is a lot trickier.

Richard
That is quite true but those 4L80e transmissions are far from stock. I have researched the Hughes and Monster transmissions. If I was going to go with a purpose built custom transmission I would likely lean toward the six speed, maybe 6L90. In the bigger vehicles, like an Escalade, after 2007 I could likely find a controller to run the engine (most any LS controller will drive a 8.1L) and six speed trans.
 
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