Engine/Tranny Upgrade
GM-Or-Bust!
03-08-2005, 12:45 AM
I have '90 98 Regency Brougham and I swapped out the original 3800 engine & Tranny for a '95 3800 which came from out of a Bonneville.It was a direct bolt on, no modifications needed. Can I go any newer than that without needing to make any major modifications?
1990TS
03-17-2005, 09:39 PM
Getting it bolted in is the easy part. Getting all the proper wiring harness changes done is the more difficult part. Did you get this combo running yet? The PCM's are totally different and so is the transmission 4t60 vs. 4T60E that is PCM controlled. I think the best way to do this swap would be to get the PCM and wiring harness from the Bonneville too. And have the factory service manual for both vehicles so you could compare connectors, terminals and wiring. You could get this engine to run with the original electronics from the 3800, but it would not run too well, certainly not up to it's full potential. Also you would most likely want to get the air intake from the 1995 Bonneville too, as the PCM was located in it. There are also some exhaust system differences so you would want that from the 1995 car too. To go to any newer engine would be almost pointless as the Series II L36 3800 Vin "K" was new for 1995 and then became OBD II for 1996, same HP, more electronics. It's been the same through 2005 with the exception of the new Series III supercharged 3800 used in the Grand Prix since 2004 rated at 265 HP.
Hansnet
03-18-2005, 01:19 AM
I have '90 98 Regency Brougham and I swapped out the original 3800 engine & Tranny for a '95 3800 which came from out of a Bonneville.It was a direct bolt on, no modifications needed. Actually I would like to know how you did it and some pics since in 95 GM introduced the Series II 3.8 (205hp, 230lb) which was on the hybrid OBD system therefore it will not direct swap into any car prior 1995 without semi-significant wiring work.
Can I go any newer than that without needing to make any major modifications? Anything is possible if you can swap out a Vin C to a Vin K. Note 1995-2003 USED THE EXACT SAME MOTOR AS A 1995 BONNEVILE (L36).
Getting it bolted in is the easy part. Getting all the proper wiring harness changes done is the more difficult part. Did you get this combo running yet? The PCM's are totally different and so is the transmission 4t60 vs. 4T60E that is PCM controlled. I think the best way to do this swap would be to get the PCM and wiring harness from the Bonneville too. And have the factory service manual for both vehicles so you could compare connectors, terminals and wiring. You could get this engine to run with the original electronics from the 3800, but it would not run too well, certainly not up to it's full potential. Also you would most likely want to get the air intake from the 1995 Bonneville too, as the PCM was located in it. There are also some exhaust system differences so you would want that from the 1995 car too. To go to any newer engine would be almost pointless as the Series II L36 3800 Vin "K" was new for 1995 and then became OBD II for 1996, same HP, more electronics.
yeah what he said......
It's been the same through 2005 with the exception of the new Series III supercharged 3800 used in the Grand Prix since 2004 rated at 265 HP.
Actually 2003...then the Series 3 N/A Motor came out...(bye bye plastic intake)
I am really dying to see some pics of this swap and how you did it since I thought it was quite difficult.....
How did you deal with the OBD Hybrid setup from the 95????
Also pulled this FAQ..might be a little more informative:
"Can I add a Supercharger to my car?"
This is one of the most often asked questions on this and other forums. Having a NA (naturally aspirated, as opposed to force-fed) Bonneville and seeing a Supercharged car at a wrecker is enough to make anyone drool. Especially when you see just how easily that Eaton Blower comes off of there! Is it possible to just bolt one up? NO. There are other possibilites, though, and none are cheap.
The reasons this will not work are extensive. The L27 and L36 NA powertrains are actually quite different when compared to the L67 (SC). The heads are different, the lower intake is different, with different injector placement, the fuel rail is different, and the compression ratio is also different. And pushrods, lifters, and rockers. Now we get nasty. The L67 gets a heavy-duty Transaxle, too. Either the 4T60-E(HD) or the 4T65E(HD). Then there's the PCM. And the engine wiring harness to go with it. This doesn't even get into the little things. About the only thing these cars really have in common other than outside appearance is the Throttle Body.
So what are my options? First, you can find a salvaged drivetrain, and drop the whole thing in. Engine, Trans, wiring harness, and PCM. You can get one from a Bonneville or a Grand Prix. Very expensive by the time you're done. If you really want this, you could sell your car and buy a SC model for less. And alot less trouble.
Second option would be an aftermarket Supercharger. This mod will run you over $3000 US. You still have the problem of possibly killing your transaxle, 'cuz you still don't have the heavy duty version. Once again, you could sell your NA Bonneville, combine it with the $3000+ you would have spent on this mod, and buy a newer SSEi or SC SSE, SLE or SE (rare, but they're around).
Another option, which is more practical and a helluvalot cheaper is a Turbo. There's room for it, and they're easier to set up. It would have to be a custom job, 'cuz nobody makes a kit YET.
Note from 99bonnevilleSE:
"Just want to make a note, it would actually be about the same price to do a turbo kit and a supercharger kit. Just the turbo has more potential for power at the lower boost levels and can be under boost faster depending on how large or small you go."
Now what is REALLY practical? The 3800 NA is no slouch, and it has alot more potential than the little bit Pontiac took advantage of. For less money than we've been talking about, you could do the exhaust, intake, maybe a chip, and possibly still have money to work over the valvetrain. We have a couple members here that have done just that, and they spank stock SSEi's quite easily.
What's your preference? It'll have to be something other than just bolting up an Eaton M62 or M90, and everyone will choose a different path, but in the end, you choose the one that's right for you and your car.
Can I go any newer than that without needing to make any major modifications? Anything is possible if you can swap out a Vin C to a Vin K. Note 1995-2003 USED THE EXACT SAME MOTOR AS A 1995 BONNEVILE (L36).
Getting it bolted in is the easy part. Getting all the proper wiring harness changes done is the more difficult part. Did you get this combo running yet? The PCM's are totally different and so is the transmission 4t60 vs. 4T60E that is PCM controlled. I think the best way to do this swap would be to get the PCM and wiring harness from the Bonneville too. And have the factory service manual for both vehicles so you could compare connectors, terminals and wiring. You could get this engine to run with the original electronics from the 3800, but it would not run too well, certainly not up to it's full potential. Also you would most likely want to get the air intake from the 1995 Bonneville too, as the PCM was located in it. There are also some exhaust system differences so you would want that from the 1995 car too. To go to any newer engine would be almost pointless as the Series II L36 3800 Vin "K" was new for 1995 and then became OBD II for 1996, same HP, more electronics.
yeah what he said......
It's been the same through 2005 with the exception of the new Series III supercharged 3800 used in the Grand Prix since 2004 rated at 265 HP.
Actually 2003...then the Series 3 N/A Motor came out...(bye bye plastic intake)
I am really dying to see some pics of this swap and how you did it since I thought it was quite difficult.....
How did you deal with the OBD Hybrid setup from the 95????
Also pulled this FAQ..might be a little more informative:
"Can I add a Supercharger to my car?"
This is one of the most often asked questions on this and other forums. Having a NA (naturally aspirated, as opposed to force-fed) Bonneville and seeing a Supercharged car at a wrecker is enough to make anyone drool. Especially when you see just how easily that Eaton Blower comes off of there! Is it possible to just bolt one up? NO. There are other possibilites, though, and none are cheap.
The reasons this will not work are extensive. The L27 and L36 NA powertrains are actually quite different when compared to the L67 (SC). The heads are different, the lower intake is different, with different injector placement, the fuel rail is different, and the compression ratio is also different. And pushrods, lifters, and rockers. Now we get nasty. The L67 gets a heavy-duty Transaxle, too. Either the 4T60-E(HD) or the 4T65E(HD). Then there's the PCM. And the engine wiring harness to go with it. This doesn't even get into the little things. About the only thing these cars really have in common other than outside appearance is the Throttle Body.
So what are my options? First, you can find a salvaged drivetrain, and drop the whole thing in. Engine, Trans, wiring harness, and PCM. You can get one from a Bonneville or a Grand Prix. Very expensive by the time you're done. If you really want this, you could sell your car and buy a SC model for less. And alot less trouble.
Second option would be an aftermarket Supercharger. This mod will run you over $3000 US. You still have the problem of possibly killing your transaxle, 'cuz you still don't have the heavy duty version. Once again, you could sell your NA Bonneville, combine it with the $3000+ you would have spent on this mod, and buy a newer SSEi or SC SSE, SLE or SE (rare, but they're around).
Another option, which is more practical and a helluvalot cheaper is a Turbo. There's room for it, and they're easier to set up. It would have to be a custom job, 'cuz nobody makes a kit YET.
Note from 99bonnevilleSE:
"Just want to make a note, it would actually be about the same price to do a turbo kit and a supercharger kit. Just the turbo has more potential for power at the lower boost levels and can be under boost faster depending on how large or small you go."
Now what is REALLY practical? The 3800 NA is no slouch, and it has alot more potential than the little bit Pontiac took advantage of. For less money than we've been talking about, you could do the exhaust, intake, maybe a chip, and possibly still have money to work over the valvetrain. We have a couple members here that have done just that, and they spank stock SSEi's quite easily.
What's your preference? It'll have to be something other than just bolting up an Eaton M62 or M90, and everyone will choose a different path, but in the end, you choose the one that's right for you and your car.
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