Turbo 3800 T56 Grand Prix

bs009

Greasemonkey
Jul 26, 2008
119
43
Smashville
R3rOuAg.jpg

A9uDXqR.jpg



Hey all, thought I'd finally introduce my car seeing as I've never done that in the 13 years that I've had an account here. I come and go so I haven't stuck around too often in the past.
Really cool to see that this forum is still so active in a world where fbook seems to be killing off forums. I've found a lot of good info here over the years.

Story below but here's the TLDR:
1982 Grand Prix Brougham, been my car since 2005 ish

Drivetrain:
Stock 3800 series 2 with some light head porting. L67 shortblock with an L36 top end
Holset Hx35 turbo running ~20 psi right now
T-56 Magnum close ratio trans
stock 2.41:1 7.5" 10 bolt. Pending new axle that has been ordered a while back

other cool things:
- Boxed frame with Hellwig's frame FX kit
- Blazer knuckles
- LS1 rear brakes
- lowering springs
- 34mm front sway bar
- Hellwig 19mm pro-touring rear sway bar
- IROC wheels
- working AC controlled by the 1998 PCM

So this car is a car I've had since I was 14, it was my grandma's and then my uncle's car before I had it. The original engine was the 4.1 Buick v6 but it had had a lot of issues even after being rebuilt a few times. In hindsight it may have just been a shoddy machine shop that did poor work though. I'm sure it could have been fixed with enough time but we didn't go down that route. We swapped in an L27 and 700r4 in horrible fashion, but it was better than the 4.1 at least. It was fuel injected so that was a plus, but we had to modify the intake so much that it didn't really run well, and the trans had so many issues that it just didn't work as well as I had liked it to.

9TlaxWT.jpg

Obviously from the picture you can tell it was a mess. I'm pretty sure I drove the car under 10 times with that engine

We were pretty big fans of the 3800 engine and I still am today really and I wanted to put in something that was actually intended to be RWD and would work properly. So in college I decided to swap in a RWD L36 from a Camaro. This would give it more power than the L27, it would actually run well, and I'd be able to run it with a manual trans because that was an option for the Camaros. At the time though my daily was a 1999 Regal GS so a naturally aspirated car was not an option in my mind so I decided it needed a turbo. In my head this was going to work flawlessly from what I've heard about the T5 from Mustang forums.

So I bit off a lot at that time, I tore the body off the frame and boxed the frame, swapped in new shocks, 34mm front swaybar, a 19mm rear sway bar, and ran better fuel system.
Oh and did everything needed to hang a turbo off of the L36.

cM2ySjZ.jpg

KwT915C.jpg


FDINFpc.jpg

LvTyy3w.jpg


ZjrVVMh.jpg

f4XtlwS.jpg

bQ4ow4P.jpg


In hindsight I would have done the whole exhaust system differently knowing what I know now about turbo manifolds.


Eventually scrounged up some seats for it from a w-body Monte Carlo that didn't interfere with the shifter too

C5NBCyM.jpg


The swap took longer than I intended of course being a broke college student, but eventually I graduated and got a job and was able to finish it. The engine and turbo worked great, but as soon as I started to go above wastegate pressure I shredded the T5.

mOfDVu2.jpg


Since then it had been running a 4l60e instead since it was a little more durable than the T5, but still was pretty horrible. Good stick shift transmissions are pretty expensive and the 4l60e is a dime a dozen in comparison. This was always intended to be temporary until I could figure out how to get a T56 in the car that could actually handle the power.

pIYyy3E.jpg


It's also proven itself on the last two power tour trips as well

nvh5HP9.jpg

o1n3ExK.jpg

lB0fGH9.jpg


Eventually swapped out all of the gauges with autometer gauges that would play nice with the EFI motor

cAOAkiN.jpg


Swapped over to rear LS1 brakes and blazer spindles up front
c7ePRTP.jpg


Eventually I blew the L36 motor and swapped everything over the L67 shortblock from my 99 Regal and it's been working pretty well since then.

C64BQU3.jpg

O7E1RwQ.jpg


The engine bay has come a long way since I first built it:
EYnjkee.jpg

BSD6FyO.jpg


4 years later and I've actually finished the transmission swap with a T56 Magnum.

Zdx2RnV.jpg

ptzZcAf.jpg

qq93Wu5.jpg

B1hAZBk.jpg

8WVa8E3.jpg


afaik, I'm one of the few who have actually mated a 3800 to a T56 trans and I'm pretty sure everyone has done it differently because their details wouldn't have worked for me.
I also finally replaced the front springs, added a bump steer kit, and swapped over to a quicker steering box.

Biggest issue I have with the car now is the 2.41:1 rear gear ratio. I ordered a new rear end for the car to solve that issue but lead times are ridiculous for parts right now so it'll be a while before that gets here. I'm also waiting for my new wheels to arrive before I can install the new brakes on the front too. Eventually I'd like to get a cam in the engine, redo some of the exhaust and really see what this thing can do but for right now I'm happy with where it's at
It's been a long road with this thing but things are slowly coming together for it!


I have a few more things happening for the car this year so stay tuned for that!
Also if you find yourself on Hot Rod Power Tour next week look out for me and the car, I try to be friendly usually :LOL:
 
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carnutjw

G-Body Guru
Supporting Member
Sep 17, 2017
536
93
Power Tour this year? I remember seeing your car in 2018
 

Longroof79

Rocket Powered Basset Hound
Oct 14, 2008
11,757
113
Gainesville, Fl
An amazing, unique ride. Thanks for sharing the specifics (and pics) with us. (y):cool:(y) I can appreciate the amount of work that went into it.
 
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Reactions: 3 users

81cutlass

Comic Book Super Hero
Feb 16, 2009
4,316
113
Western MN
Really cool!

I put together an l67 swap in my fbird in college and never got to putting it in a G body.

It's kinda a bummer 3800 stuff is kinda dead.

Your using the stock ecm I'm assuming? Maf and HPtuners? How much boost?
 
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Reactions: 2 users

bs009

Greasemonkey
Thread starter
Jul 26, 2008
119
43
Smashville
Power Tour this year? I remember seeing your car in 2018
Yupp! As in leaving this weekend for it haha!
Oh man that's really cool! 2018 was a really good year for me at Power Tour, it was the first real road trip the car had done with the new engine and I was really on the fence about making such a long drive from Michigan, but I'm really glad I did it!
The car had a cooling issue the first day due to some cheap Amazon fans I was using and afterward was smoking the rest of the trip from burnt valve stem seals, but otherwise it was a really good trip!
Really cool!

I put together an l67 swap in my fbird in college and never got to putting it in a G body.

It's kinda a bummer 3800 stuff is kinda dead.

Your using the stock ecm I'm assuming? Maf and HPtuners? How much boost?
Nice! Not an easy swap for sure unless you can get your hands on the Holden supercharger. I really like the idea of a supercharged RWD 3800, I've thought about running one someday with a much larger blower than the stock blower to see what it can do haha!

Using the stock PCM for now, tuning it myself with DHP and tuning the MAF right now. I'm looking at converting the car to Holley HP EFI though soon to give me more flexibility with what I can do with the tune.
Right now I just have the stock cam so tuning is easy, but I am running E85 in it so there are some challenges with it. I've ran as much as 22 psi before I blew a head gasket, since then I've come down a little bit more. I think I just need to retorque down the head studs to be able to turn it back up.
Eventually I want to build another motor for it though and do a few things to make it handle even more cylinder pressure, but I think I'm at least a year away from doing that.
 
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Reactions: 4 users

81cutlass

Comic Book Super Hero
Feb 16, 2009
4,316
113
Western MN
Yupp! As in leaving this weekend for it haha!
Oh man that's really cool! 2018 was a really good year for me at Power Tour, it was the first real road trip the car had done with the new engine and I was really on the fence about making such a long drive from Michigan, but I'm really glad I did it!
The car had a cooling issue the first day due to some cheap Amazon fans I was using and afterward was smoking the rest of the trip from burnt valve stem seals, but otherwise it was a really good trip!

Nice! Not an easy swap for sure unless you can get your hands on the Holden supercharger. I really like the idea of a supercharged RWD 3800, I've thought about running one someday with a much larger blower than the stock blower to see what it can do haha!

Using the stock PCM for now, tuning it myself with DHP and tuning the MAF right now. I'm looking at converting the car to Holley HP EFI though soon to give me more flexibility with what I can do with the tune.
Right now I just have the stock cam so tuning is easy, but I am running E85 in it so there are some challenges with it. I've ran as much as 22 psi before I blew a head gasket, since then I've come down a little bit more. I think I just need to retorque down the head studs to be able to turn it back up.
Eventually I want to build another motor for it though and do a few things to make it handle even more cylinder pressure, but I think I'm at least a year away from doing that.

My M90 with a 2.8" pulley and S1X cam made 11 PSI on E85 and was very close to maxing out the stock l67 maf. Can always scale it or go to the N* or LS maf but I never got there. Ended up running a 12.60 with some additional time left on timing and chassis tuning that I never chased.

I'll be on PowerTour so I'll hopefully run across you :)
 
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Reactions: 4 users

Texas82GP

Just-a-worm
Apr 3, 2015
7,651
113
Spring, Texas
R3rOuAg.jpg

A9uDXqR.jpg



Hey all, thought I'd finally introduce my car seeing as I've never done that in the 13 years that I've had an account here. I come and go so I haven't stuck around too often in the past.
Really cool to see that this forum is still so active in a world where fbook seems to be killing off forums. I've found a lot of good info here over the years.

Story below but here's the TLDR:
1982 Grand Prix Brougham, been my car since 2005 ish

Drivetrain:
Stock 3800 series 2 with some light head porting. L67 shortblock with an L36 top end
Holset Hx35 turbo running ~20 psi right now
T-56 Magnum close ratio trans
stock 2.41:1 7.5" 10 bolt. Pending new axle that has been ordered a while back

other cool things:
- Boxed frame with Hellwig's frame FX kit
- Blazer knuckles
- LS1 rear brakes
- lowering springs
- 34mm front sway bar
- Hellwig 19mm pro-touring rear sway bar
- IROC wheels
- working AC controlled by the 1998 PCM

So this car is a car I've had since I was 14, it was my grandma's and then my uncle's car before I had it. The original engine was the 4.1 Buick v6 but it had had a lot of issues even after being rebuilt a few times. In hindsight it may have just been a shoddy machine shop that did poor work though. I'm sure it could have been fixed with enough time but we didn't go down that route. We swapped in an L27 and 700r4 in horrible fashion, but it was better than the 4.1 at least. It was fuel injected so that was a plus, but we had to modify the intake so much that it didn't really run well, and the trans had so many issues that it just didn't work as well as I had liked it to.

9TlaxWT.jpg

Obviously from the picture you can tell it was a mess. I'm pretty sure I drove the car under 10 times with that engine

We were pretty big fans of the 3800 engine and I still am today really and I wanted to put in something that was actually intended to be RWD and would work properly. So in college I decided to swap in a RWD L36 from a Camaro. This would give it more power than the L27, it would actually run well, and I'd be able to run it with a manual trans because that was an option for the Camaros. At the time though my daily was a 1999 Regal GS so a naturally aspirated car was not an option in my mind so I decided it needed a turbo. In my head this was going to work flawlessly from what I've heard about the T5 from Mustang forums.

So I bit off a lot at that time, I tore the body off the frame and boxed the frame, swapped in new shocks, 34mm front swaybar, a 19mm rear sway bar, and ran better fuel system.
Oh and did everything needed to hang a turbo off of the L36.

cM2ySjZ.jpg

KwT915C.jpg


FDINFpc.jpg

LvTyy3w.jpg


ZjrVVMh.jpg

f4XtlwS.jpg

bQ4ow4P.jpg


In hindsight I would have done the whole exhaust system differently knowing what I know now about turbo manifolds.


Eventually scrounged up some seats for it from a w-body Monte Carlo that didn't interfere with the shifter too

C5NBCyM.jpg


The swap took longer than I intended of course being a broke college student, but eventually I graduated and got a job and was able to finish it. The engine and turbo worked great, but as soon as I started to go above wastegate pressure I shredded the T5.

mOfDVu2.jpg


Since then it had been running a 4l60e instead since it was a little more durable than the T5, but still was pretty horrible. Good stick shift transmissions are pretty expensive and the 4l60e is a dime a dozen in comparison. This was always intended to be temporary until I could figure out how to get a T56 in the car that could actually handle the power.

pIYyy3E.jpg


It's also proven itself on the last two power tour trips as well

nvh5HP9.jpg

o1n3ExK.jpg

lB0fGH9.jpg


Eventually swapped out all of the gauges with autometer gauges that would play nice with the EFI motor

cAOAkiN.jpg


Swapped over to rear LS1 brakes and blazer spindles up front
c7ePRTP.jpg


Eventually I blew the L36 motor and swapped everything over the L67 shortblock from my 99 Regal and it's been working pretty well since then.

C64BQU3.jpg

O7E1RwQ.jpg


The engine bay has come a long way since I first built it:
EYnjkee.jpg

BSD6FyO.jpg


4 years later and I've actually finished the transmission swap with a T56 Magnum.

Zdx2RnV.jpg

ptzZcAf.jpg

qq93Wu5.jpg

B1hAZBk.jpg

8WVa8E3.jpg


afaik, I'm one of the few who have actually mated a 3800 to a T56 trans and I'm pretty sure everyone has done it differently because their details wouldn't have worked for me.
I also finally replaced the front springs, added a bump steer kit, and swapped over to a quicker steering box.

Biggest issue I have with the car now is the 2.41:1 rear gear ratio. I ordered a new rear end for the car to solve that issue but lead times are ridiculous for parts right now so it'll be a while before that gets here. I'm also waiting for my new wheels to arrive before I can install the new brakes on the front too. Eventually I'd like to get a cam in the engine, redo some of the exhaust and really see what this thing can do but for right now I'm happy with where it's at
It's been a long road with this thing but things are slowly coming together for it!


I have a few more things happening for the car this year so stay tuned for that!
Also if you find yourself on Hot Rod Power Tour next week look out for me and the car, I try to be friendly usually :LOL:
Very cool build! I'll bet it's really fun to drive!
 
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Turbo Zach

Comic Book Super Hero
Sep 8, 2015
2,534
113
50130
You are my new idle. I have a Turbo Monte. I gathered all the parts and engines to put a Series Two in my car, but I put it on hold years ago and built my original 3.8 into a intercooled blow through engine. I can say I am happy with the choice. That car runs really good. Two years ago I bought a 2003 GS. I have a stage one kit on that car. Tuned ECM and a 3.5 pulley. It runs pretty good too. I recently bought a 81 Buick Century. The plan is to put a Series Two in that car and later the Supercharged engine out of the GS in that car. The GS still has a lot of life left in it though, so it will be a while. I have been daily driving the Century because it gets good mileage and is comfortable to drive, but I can't wait. I think you have an awesome combination. I don't know why more people don't go that route. Probably because it is not all laid out for them? Love your car and what you have done to it.
 
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Reactions: 9 users

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