Thread: 1997 Pontiac Grand Prix to Supercharged engine swap

Hey guys my dad has a 58,000 mile Grand Prix that just spun the number 6 Cylinder Rod bearing. It tore the crank up pretty bad

A buddy of his has a running complete supercharged 3800 engine that he will sell my dad for $250.

I know I will have to splice a map sensor connector onto my dads harness.

He wants to keep his stock trans.

Now what do we need to get for a computer? Will a company flash his stock computer over with a bin from a different car or would it be better to but a pcm out of a GTP model?

I'm not to sure what series engine it is but I should know by tonight.

I have searched around the forums but really haven't found any info on a complete swap, only the top swaps. I'm not a newb at engine swaps but not really familiar with GM cars, I have a 6bolt swapped 500hp DSM.

Ok I confirmed it is a series II engine.

Ok I found the adapter for the map and the boost bypass valve along with the injector pigtails.


Now the alternator mounting looks different, can I use the old L36 bracket and alt? It looks as if it needs a longer belt.

Or should we just buy a alt off a 98 GTP?

One thing I've always wondered about swapping a S/C into a GT.... What happens to the DIC? Would you need a whole new DIC that is able to show boost? Or is there something you can do to enable the boost gauge on the GT?

Ok Injectors have the same harness.

This is a Grand Prix SE 3.8.

ZZP said they would do the ecu for 120, all I need to do is figure out the vacuum routing and hopefully she fires up the first time.

Well he doesn't have a 4t65e trans but we are gonna pull this engine again to rebuild it in the fall and he will probably get the ecu reflashed the harness from a 98 and the trans from a 98.

I hope ZZP flashes the ecu right... They had options for the 97GT with Top swap but I added notes to it. L67 Complete Engine swap with the 97 SE 4T60 Trans.

I got a new supercharger coupler, Alt Volt booster, L67 Swap harness kit for the map sensor, the ecu, and a gates micro v belt.

I hope this thing runs...

Here are some pics not 100% finished, waiting on ecu, SC Coupler, and SC Belt.

One way check valve?

Originally Posted by Bio248

i hope to god that you guys got someone who is able to tune that car handy because that 4t60e is NOT going to like boost at all. it might not even shift until you let off the throttle.

Nope just zzperformance.
I wonder if a vacuum pump would work, like the cammed low vacuum v8 guys use?

I have a buddy getting rid of a 97 gtp, its collecting dust in his yard and hes about to get it hauled away by the junkyard guys.
depending on how interested you are I could get the tranny out of it.

and if anyone is interested in a top swap 97 gtp lemme know.

Well we got her done, Started right up was a idle was a little rough. But I let it warm up bled the coolant system. Gave it a couple of blips and it smoothed out.

This engine has set for 6 years, planning on changing the oil in 50 miles. It has Mobil1 10W30 Fully Synthetic with an AC Delco Filter right now, will be getting same oil new and a new filter.

We took it out confirmed no leaks and now odd smells, no CELs, and topped everything off. It ran great, shifted really firm and no problems at all.

Then I had my friend in his stock Eclipse Spyder GS-T Turbo film us as we went by to see if any smoke or odd noises. Sounded great and walked away from it. Will post a vid.

It shifted great under full boost in auto and shifting it manually. There was no lag and shifted aggressively. This car would be great for bracket racing at the strip the times would be very consistant.

My dad is very pleased with how well it runs. I still have to wire the pink wire into the ICM for the boost bypass valve as it is now he runs it with no traction control. It melts the tires off too

He doesn't rip on his cars at all but we had to see what it would do.

On the intake it is short ram right now till I can order some Aluminum piping and couplers then it will be cold air in the fender.

I can't wait to get a better tranny when this one is done. Then comes the modular pulley system, injectors, fp rewire and a hptuner. But till then she runs good enough.

Here are some pics of the engine done and the custom PCM mount.

Originally Posted by Lionel

I have a buddy getting rid of a 97 gtp, its collecting dust in his yard and hes about to get it hauled away by the junkyard guys.
depending on how interested you are I could get the tranny out of it.

and if anyone is interested in a top swap 97 gtp lemme know.

Does it have the 4t65? if so how much shipped to 26726?

dont the supercharged 97's have the 4t65? it's a gtp anyway.

I work in a warehouse and get good shipping rates, I just need to find out the weight of the tranny, anyone know?

once i get the price on shipping I'll get you a price. I'm from eastern canada so it could be a little high.