GN 3.8 swap into 2nd Gen F Body

NEOSpeeder77

New Member
Joined
May 27, 2015
Hi, new to the forums, and this is my first post, so prior apologies if my thread location is wrong...but to the matter at hand.

Im looking at swapping a Turbo 3.8l in a 1981 Pontiac Firebird. The vehicle is currently set up with a 3.8l. So Im imagining the bolt up would be fine.

However what all is really required doing this swap (if possible). A general list of items would be fine, however as much detail as possible would be appreciated.

Yes any big or small block swap would be nifty, but I really wanted to do something a little different, and the engine itself fascinates me.

Thank you
 
for intercooled you need to find a 3.8T LC2 engine pulled as complete as possible , with engine wiring harness , ecu , relays , esc module, sensors, ignition module, coilpack and brackets , you dont need the dash harness but you will need to do your homework to integrate the lc2 engine harness needs to your vehicle
anything you're missing or want to upgrade youll need to buy and they wont be cheap and will add up the costs $$$$$ ..things like .120A alternator (170) , intake (250), injectors(300) and matching chip (85), manifolds (200-1000), turbo (600-2000), downpipe (50-600), intercooler (100-1000) , MAf sensor or tranlator and lT1 sensor ..(100-300) , and air inlet assembly and filter .. there goes another benjamin or two and theres some unique brackets to the lc2 for accesories that add up the benjamins oh and the belt tensioner isnt a cheap item or easy to get a hold of if you need one .
depending on what options you want like a/c , pwr steering etc youll need those items too for the LC2 as the ps pump is unique and youll need a remote reservior for it
you'll need electric fan(s) for the radiator
a trans that can hold the power of the turbo motor and a converter for turbo ( 2004r or a built BOP 350 or BOP th400)
you may need to get a driveshaft made to fit depending on the trans you go with
also the rear gears should be upgraded to 3.42 and might as well do a posi while your there
then you need an efi fuel system..inline or external pump or a custom fuel tank with a pump in it .

drop motor in and then wire it into your engines fuse block plug for starter and ignition, volt lamp, etc
, youll need to add some switched circuits to feed the coilpack

now youll have an almost 30yr old LC2 and all the fun that goes with ownership like fixing ,tuning and maintaining. at minimum you should have a scanmaster and boost gauge , if you dont have rally pak add an oil and water temp gauge and consider a fuel press gauge, and a wideband

also keep in mind that buying all as a pulled engine can save many $$ but any pulled engine is still a used engine and usually theres a reason it was pulled . even if the motor was running doesn't mean its without issues .. you really should refresh the motor and seals before it goes in its parts are almost 30yrs old and that includes the wiring so just getting it into the car is one thing at that point you now basically have a 30yr old car that may need work to getting it running properly and that can rack your brain but its is easier if the mechanicals are sound to begin with .. no blown head gaskets , leaking rear main seal, worn out timing chain , worn cam lobes, bad valve seals , bent pushrods , burned valves , leaking intake gasket
then theres the accessory stuff .. tensioner that bounces , ac compressor that needs replacing , ps pump that chirps, waterpump that weeps, thermostat that should be replace , throttlebody that needs to be rebuilt for shaft wobble and bad seals , turbo that needs rebuild (light oil smoke at tailpipes is not normal) , hoses and clamps at intercooler that need upgrading
then the electrical stuff like reman mafs that dont work properly , ignition modules that seem ok but go south when hot , plug wires that need replacing

and then you get to play the lets go faster game ..bigger turbo , alky , higher stall torque converter , bigger injectors , bigger inlet setup, better exhaust ., bigger downpipe , better heads ..maybe a roller cam
then the its fast it should be pretty ..so on goes the fancy valve covers , some chrome and the addiction known as powder coating $$$
in the end when it works the smile of acceleration makes all the aggravation , time and expense disappear .
 
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Lol^^^.. I 100% agree with post #2... Mine wasn't "as" involved as a 1981 trans am would be since its still another G-body but the rest of that post is gospel, lots and lots of Time, Headaches, and of course money ....did I say money?.$$
 
We built one a few years back.

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The stock GN accessory drive does not work as well as the stock a/c system would be a nightmare to make fit. Beyond that you can use stock location intercooler and downpipe. We used an FAST but you could use a stock wiring harness adapted to the car. The accessory drive will be your biggest hurdle as it will have to be a custom one off. I would also suggest if you want A/C to retrofit it with a Vintage Air unit.
 
The 1981 Turbo Trans Am above was a neat project and exceeded all the owner's expectations although he insisted to retain AC, and this became our major challenge!

Not only was a new mount bracket needed for the AC compressor, there was no way in hell to snake a 3" down pipe around the AC box to the exhaust.

We also had to get creative with the fuel system, and we started with a new fuel tank and fabricated a fuel pump sender/hanger. Of course we had to deal with fuel line mods to complete the fuel system properly.

The transmission was also from a GN and a custom driveshaft was included.

When we finished our work, it went to a restoration shop for almost 2 years to make the car look like new inside and out!

All the Trans Am's are a great ride with a turbo Buick drivetrain, factory or custom! :)
 
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5.3 LS engine and a 88mm turbo and let it eat. Seriously. I love the turbo Buicks, but for 1/3 the cost you will make more power with the new truck engine.
 
5.3 LS engine and a 88mm turbo and let it eat. Seriously. I love the turbo Buicks, but for 1/3 the cost you will make more power with the new truck engine.


It all depends on what you want. You can throw in an a LS and be like all the rest of the sheeple or choose to go the road less taken with another platform. Don't get me wrong I love the LS platform and have built a few cars with them but its also overdone. jmho
 
I built a 67 Firebird in 09 and installed a new GM LS1 crate motor and drove it for 6 months and swapped out the LS1 for an LC2. I drove the car on the Power Tour in 09 with the LS1 and it seemed like every car there had a LSx motor of some sort. I drove the car on the Power Tour in 10 with the LC2 and Freiburger from Hot Rod came over and talked to me the first day and said he thought it was a cool engine swap and put pictures up on Hotrod.com. I just hate seeing the same thing under every hood even if it does "make sense".
 
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