3.8 gn engine in 71 cj5

hello there. was wondering if anyone might have some input on putting a 3.8 gn engine in an early 5.like what i might need for the wiring harness and such.

 

Oddfirejeeper,

Do you mean the 3800-- like in a current Buick, or Pontiac?

If so yes--- I saw a rock crawler on ebay a year ago that did with single port fuel injecton and supercharger- 270 HP You use the 3800 Camaro flywheel and clutch and a custom adapter that you have to build yourself.


If you mean an earlier-- like 1980ish 3.8 RWD even-fire that is just a matter of getting a
Sunbird flywheel and clutch which is even-fire ballanced.

 

it's a 3.8 turbo out of a 80 something gn. fsm? and howdy from here as well. just not sure if i really want to do it or not. i'm all stock except for body and tires. 3.8 would really make it scoot though.

 

forgot about the flywheel. glad i'm asking questions befor i really start to get into it. i think it's around 86 or 85 gn

 

yeah it's still a rwd i heard it will bolt right up to my t-14 and same bell housing

 

OH the GN! turbo Regal ! That is a "Stage II" Buick V6 racing engine!
If you can keep it cool in your Jeep with a turbo---- just get the harness aftermarket-- and a BIG radiator!


There is an entire aftermarket for Turbo Buicks and a Turbo Buick WWW club full of experts online-- do a WWW search under "Buick V6" and you will find them easy--- tons of such parts.

 

Yes it will bolt-up to a T-14-- but need a even-fire Flywheel ( can modify odd-fire one) and clutch. Some have a 4 bolt main-- AL heads with big valves. Some were run in Indy 500 cars too! SUPER TECH engines!

You could build one aspirated (carb) or put TBI on it-- and build a 300 HP engine that will take the punishment--- high volume Oil pumps--- and all that Jazz.


GN Stage II engines are rare and $$$ and can be made to do 8000 RPMs all day long with enough $$$ forged pistons, ballancing and all that racing stuff--- its the elete Buick V6 version. There was an odd-fire version made for a couple months of production too--- very rare-- in early 1977--- seen one and had the pan off in a bone yard.

 

yeah alot of hp for stock drivetrain. i guess just can't really open it up till i'm ready for newer front.

 

still debating the swap though. i know if i try to keep it stock it will be worth it in the long run

 

resale $$$$ depends on how nice (fewer hacked up parts) install is. welcome from Northwest IN

 

thanks alot for the input people. i'm going to have to do alot of research on the engine swap. i love the v-6 but want something with more aftermarket upgrades for the engine. right now i'm running a 600cfm carb on my 2bbl intake and need to get it jetted down a tad. is there a 4bbl intake for a 231 odd-fire?

 

I have an 84/85 vintage 3.8 sfi turbo in my 67. I assume you already have a 225 under the hood? The mechanical swap was pretty easy. Use the odd fire flywheel and the 3.8 harmonic to have the engine balanced. T86a, in my case, bolted right up. Use same part no. pilot bearing in the crank. Check to make sure the crank is a turbo crank- rolled filets. Consider a new front pan while you have it apart. 225 short water pump bolts right up to late model front pan. I have had no cooling problems, but I added a high vol water pump and a pusher electric fan with the AC. AC and Alt bracket are peculiar to turbo car. You can use 225 water pump pulley by adding a spacer and use the 3.8 crank pulley. You will need to have custom exhaust made for the down pipe ( from turbo to muffler). I used 3.8 mainfold on pass side and 225 manifold on driver side. Custom crossover connects the two. Get as much of the donor harness as possible. A appropriate year service manual is invaluable to help troubleshoot the harness. The ECM , I am told , will not do well in a manual transmission application. I bought a custom chip and have had no complaints. If the motor is from a stock GN, its not a Stage motor. You will need to switch the outlet from your gas tank to 3/8 and the return line to 5/16. You will have to be a bit creative to plumb the fuel line to the motor as the Saginaw fittings are a pain. I added a completely seperate ignition hot fuse block to run the extra circuits. Nevertheless, it will haul the mail.

 

Hi there, I don't know how I missed this thread but I am close to installing the turbo in my '70 (hopefully Spring).

I have done alot of research so ask me, I may know (or not)

A. Mandery in Indianapolis has already chimed in and he has truly been there with his 1984 SFI transplant. I have riden in his rig and it is truly impressive!!

Probably not the greatest motor choice for rock climbing and slow trails but awesome on the street and dunes!!! My CJ5 is being built soley for street and dunes. Your '71 already has the strong rear axle so you have that shortcoming solved. The GN motor will produce around 385 ft lbs of torque. A stronger T90 trans may be worth the upgrade. The T14 will do for now but it may be a weakness. I'm not sure what trans Andy is running but his is doing fine so far at 15# boost :twisted: .

Is it carb'd or injected? Give me your block number (side of block --under the drivers side head) and I can cross reference it to the correct year. Do you have the complete car?

If ECM controlled, it isn't as scary as it appears. In my opinion, a lot of work up front but you will enjoy it's functionality later. I will be running pre-81 basic electronics with help from MSD. Andy (A.Mandery) uses laptop software to fine tune his which is really handy.

Where is Hamilton? Kalamazoo area?