3.8 or LLT ... I know... it's complicated
#1
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Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
3.8 or LLT ... I know... it's complicated
when I hear people say "it's complicated" when somebody asks a question about putting a 3.8 or even a LLT in a third gen, i always want to ask.. "how complicated"
let's say I want to put a LLT in my car. From what I can tell, this is what I'm looking at...
computer
wiring harness
custom motor mounts
engine
tranny
I see people doing the LS1 swap all the time... that's complicated....is it worse than that?
another related question... if SBC's are 90 degree engines, and the TTA was a 90 degree engine, then why is it so complicated to put a 90 degree engine in a third gen that previously had a 60?
sorry if these are dumb questions... i really don't know
let's say I want to put a LLT in my car. From what I can tell, this is what I'm looking at...
computer
wiring harness
custom motor mounts
engine
tranny
I see people doing the LS1 swap all the time... that's complicated....is it worse than that?
another related question... if SBC's are 90 degree engines, and the TTA was a 90 degree engine, then why is it so complicated to put a 90 degree engine in a third gen that previously had a 60?
sorry if these are dumb questions... i really don't know
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Re: 3.8 or LLT ... I know... it's complicated
I don't know what a LLT engine is. I though that maybe you typo'd LT1, but you used LLT twice, so not sure.
As for the 3.8L engine. It is a Buick engine and uses a different bellhousing bolt pattern. Need to use a BOP patterned transmission with it. With that a 700R4 won't bolt up. Most use (including the TTA) a 200-4R transmission. In which you lose the torque arm mount. So need to go with a crossmember or tunnel mount for the front of the torque arm.
If you can't find '89 TTA engine mounts then need to make some (as you listed).
Look for a thread by 'nielb', hopefully I spelled that correctly (maybe 'neilb'). He put a 3.8l turbo Buick engine in a Camaro. Has a thread on it here on the V6 board.
There are other little things that need to be changed. Sometimes the brake lines need to be moved as they interfere with the engine/frame mounts. Then possibly different front springs due to weight differences. Then exhaust manifolds and crossover and such.
The RWD (turbo) Buick heads don't clear the A/C box. If A/C is wanted there is a set of FWD Buick heads that can be used. The '89 TTA used these heads. But they have a smaller chamber which raises the compression ratio.
There isn't any real show-stoppers, just the time needed to do it.
RBob.
As for the 3.8L engine. It is a Buick engine and uses a different bellhousing bolt pattern. Need to use a BOP patterned transmission with it. With that a 700R4 won't bolt up. Most use (including the TTA) a 200-4R transmission. In which you lose the torque arm mount. So need to go with a crossmember or tunnel mount for the front of the torque arm.
If you can't find '89 TTA engine mounts then need to make some (as you listed).
Look for a thread by 'nielb', hopefully I spelled that correctly (maybe 'neilb'). He put a 3.8l turbo Buick engine in a Camaro. Has a thread on it here on the V6 board.
There are other little things that need to be changed. Sometimes the brake lines need to be moved as they interfere with the engine/frame mounts. Then possibly different front springs due to weight differences. Then exhaust manifolds and crossover and such.
The RWD (turbo) Buick heads don't clear the A/C box. If A/C is wanted there is a set of FWD Buick heads that can be used. The '89 TTA used these heads. But they have a smaller chamber which raises the compression ratio.
There isn't any real show-stoppers, just the time needed to do it.
RBob.
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Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
Re: 3.8 or LLT ... I know... it's complicated
nice! thanks...
BTW, I have a 5 speed if that makes a difference. what transmission was used with the 3.8 in the late 4th gens?
also BTW, the LLT is the 300 HP V6 from the 5th gen camaro
BTW, I have a 5 speed if that makes a difference. what transmission was used with the 3.8 in the late 4th gens?
also BTW, the LLT is the 300 HP V6 from the 5th gen camaro
#4
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Re: 3.8 or LLT ... I know... it's complicated
The main reason no one swaps 3.8s or 4.3s is that its about as much work to swap a v8, and as for the llt, cost and electronics, lets face it, not many llts are going to be lying around in JYs yet, though I for one would sure love to have one, 300 hp with the light weight and better distribution of an aluminum v6, with loads of headroom for power...yes please....but the main thing for that is figuring out the ECM/PCM stuff, because newer cars tend to have 10 million electronic things that are all tied in together, so the computer/s would probably be looking for data they wouldn't be receiving.
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Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
Re: 3.8 or LLT ... I know... it's complicated
yeah, it's probably a pipe dream... but what a NICE pipe dream.
#6
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Re: 3.8 or LLT ... I know... it's complicated
Forgot, fuel system would need upgraded as well, DI uses pressures of around 2k psi if memory serves.
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Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
Re: 3.8 or LLT ... I know... it's complicated
Not such a pipe dream: Search BUICK and you'll find plenty of Buick turbo cars here.
Because of your emissions problem (from your exhaust thread) the law generally allows the 4th gen engine swaps to the 3rd gen, if you keep all the 4th gen emissions parts with it.
So, you could put the 4th gen 3800 (which was available with a 5 speed) in your car, if you use the entire engine, the 4th gen fuel tank and vents, and the 4th gen ECM and wiring.
Basically, a totalled 4th gen would get you everything you need.
Because of your emissions problem (from your exhaust thread) the law generally allows the 4th gen engine swaps to the 3rd gen, if you keep all the 4th gen emissions parts with it.
So, you could put the 4th gen 3800 (which was available with a 5 speed) in your car, if you use the entire engine, the 4th gen fuel tank and vents, and the 4th gen ECM and wiring.
Basically, a totalled 4th gen would get you everything you need.
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#8
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Re: 3.8 or LLT ... I know... it's complicated
Not such a pipe dream: Search BUICK and you'll find plenty of Buick turbo cars here.
Because of your emissions problem (from your exhaust thread) the law generally allows the 4th gen engine swaps to the 3rd gen, if you keep all the 4th gen emissions parts with it.
So, you could put the 4th gen 3800 (which was available with a 5 speed) in your car, if you use the entire engine, the 4th gen fuel tank and vents, and the 4th gen ECM and wiring.
Basically, a totalled 4th gen would get you everything you need.
Because of your emissions problem (from your exhaust thread) the law generally allows the 4th gen engine swaps to the 3rd gen, if you keep all the 4th gen emissions parts with it.
So, you could put the 4th gen 3800 (which was available with a 5 speed) in your car, if you use the entire engine, the 4th gen fuel tank and vents, and the 4th gen ECM and wiring.
Basically, a totalled 4th gen would get you everything you need.
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Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
Re: 3.8 or LLT ... I know... it's complicated
The original post says 3.8 or LLT...
AND references the 90 degree TTA...
so I was just adding my two cents...
AND references the 90 degree TTA...
so I was just adding my two cents...
#10
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Re: 3.8 or LLT ... I know... it's complicated
The LLT doesn't spark my interest, but you'd need a complete, rear-totalled donor. With a good BCM in it. In those, the TCM is separate from the ECM. And fitting the automatic might require major floorpan surgery. Speaking of which, we have tapered front subframe rails, the 4th and 5th gens don't. This is a problem, because Cali doesn't like you moving the cats, relative to the exhaust manifolds.
The '96-'02 3.8 used a Ford based hybrid version of the T5, with deep ratios.
They only came with a 3.23:1 axle.
The '96-'02 3.8 used a Ford based hybrid version of the T5, with deep ratios.
They only came with a 3.23:1 axle.
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Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
Re: 3.8 or LLT ... I know... it's complicated
After driving a 96 Camaro with the 3.8 engine, I'd take that tranny with it, no problem.
But, if you didn't want to, you could just run the regular V8 third gen T5 behind it. The 4th gen trans has the same splines as the V8 third gen trans, so a 4th gen engine with 4th gen clutch kit and third gen V8 T5 equals a fine setup to me.
The bellhousing could be either V6 4th gen or 3rd gen, since the 4th gen 3.8 uses the front wheel drive GM metric bolt pattern, just like the 3rd gen V6 does. Its the only rear drive Buick V6 family with that transmission pattern, but they made plenty of them. GM stopped the Buick rear wheel drive transmission bolt pattern blocks when the 78-87 G-body got killed. They were all fwd pattern 3.8 blocks from 88 on.
But, if you didn't want to, you could just run the regular V8 third gen T5 behind it. The 4th gen trans has the same splines as the V8 third gen trans, so a 4th gen engine with 4th gen clutch kit and third gen V8 T5 equals a fine setup to me.
The bellhousing could be either V6 4th gen or 3rd gen, since the 4th gen 3.8 uses the front wheel drive GM metric bolt pattern, just like the 3rd gen V6 does. Its the only rear drive Buick V6 family with that transmission pattern, but they made plenty of them. GM stopped the Buick rear wheel drive transmission bolt pattern blocks when the 78-87 G-body got killed. They were all fwd pattern 3.8 blocks from 88 on.
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Car: 1985 TA
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Re: 3.8 or LLT ... I know... it's complicated
OK. Ive been looking for hours on here with no definitive answers. What is required in a buick 3800 series 2 supercharged into a 1985 305tpi car? Anything can be done but on a budget and i dont own a machine shop. Any help would be great. Thanks
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Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
Re: 3.8 or LLT ... I know... it's complicated
Use a 1987-92 3rd gen V6 700R4 or 4th gen V6 4L60E automatic transmission. You'll need to custom make your motor mounts in the front.
Use the 3800 ECM and wiring. You'll need to re-pin some of your harness stuff in the dash and under the hood as appropriate.
This will take a lot of time just with re-wiring and making mounts. If you are not up to customizing stuff then this swap isn't for you.
I'm going to at least attempt this when I get home.
Use the 3800 ECM and wiring. You'll need to re-pin some of your harness stuff in the dash and under the hood as appropriate.
This will take a lot of time just with re-wiring and making mounts. If you are not up to customizing stuff then this swap isn't for you.
I'm going to at least attempt this when I get home.
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