My L32 Swap Build Thread (20k mile update!)

[RivMan]

Hey guys, figured I'd toss together a build thread for my new DD project.

I picked up this 04 Grans Prix GT for $1700. The motor was knocking pretty bad, and it looks to have been run out of oil. The body is in great shape with no signs of Michigan rot showing on the outside.












The interior is in great shape with some regular wear and tear, it'll be great with a good cleaning and a couple misc parts. I got under the car to check for rot / any other issues, and I noticed the oil pan and trans pan were covered with quite a bit of oil. I also noticed a little bit of rust on the oil pan that had some fresh oil on it. I tapped there with a screwdriver, and this was the result:



I guess I know there's a little rust...

I was intending to buy a motor from Morad, however I found a great deal on this wrecked car locally. It's an 04 CompG with 130k miles. The motor starts, and sounds new, I ran it up and down the road and it seems to shift fine. The radiator is still good, no cracks in the trans, ect... Picked it up for $1500!













My plan is as follows:

1: Swap in the L32 Motor, it should bolt in with no drama. I'll probably swap the manifold / headgaskets while it's out.
2: Swap the exhaust off the CompG onto the GT (The GTs exhaust is a little messed up)
3: Swap the wheels and tires off the CompG onto the GT
4: Re-tune the L26 PCM to L32 Specs and treat it like a TopSwapped car (Vent the boost control solenoid)
5: DRIVE!

Once the car is up and running, here's my endgame:

6: Swap the HD Diff from the CompG Trans into the GT Trans
7: Swap the HUD and DIC into the GT
8: Swap the CompG Struts (If their still good) onto the GT
9: Swap the CompG Swaybars onto the GT
10: Swap the Red brakes onto the GT
11: Part out / Scrap the CompG

More updates soon, I hope to have the cars in the shop this weekend!

Any tips would be great, this isn't my first rodeo, but I've never messed with the new body style before.

Where's the best place to pickup these parts:
Headgaskets
LIM Gaskets
SC Gaskets
TTY Bolts needed?

Thanks
-Rob

[str3etgl0w]

Looks like fun man good luck with the build

[PurpleGuy]

Rockauto has good prices on LIM and blower gaskets. Prob have head gaskets as well. Which TTY bolts you lookin for?

[Fivefingerdeathpunch]

Dont touch the head gaskets, there is no need to.

Just change the LIM gaskets to the new upgraded style.

And on your tuning, what program are you going to use and why would you need to vent the boost solenoid? Thats the first time I've ever heard of that.

[ShadowSwept]

Looks nice. 04+ aren't my favorite but that color is awesome. Good luck with the build!

[matt5112]

rocker arm bolts are TTY.

Buy the reusable bolts from the vendors.

[MoarkatsINmuhtrailer]

i love how the gt got the spo spoiler and tips and the comp g has regular gp tips and spoiler haha

[RivMan]

I have a DHP Powertuner here to use.

This is the part if the instructions that I was reading about venting the bypass valve. I think it's required because I'm planning to use the GT's PCM.

"" Go ahead and attach the Boost Bypass Valve to the supercharger. It's held on with a bracket and two bolts. Run a vac line from the tree on the supercharger to the top nipple on the BBV. The bottom one needs to see ATMOSPHERE, because our L36 PCM's cannot control the BBV."

-Rob

[matt5112]

the L36/L26 bin cannot control the BBV.

The L67/L32 bins can.

Put the right bin on your existing PCM, and enjoy.

Or swap PCMs and harnesses, then drop the GT trans files on the PCM if you decide to run the GT trans.

[RivMan]

From what I've read, the BBV is completely controlled by vacuum except when the traction control is active. I guess I could toss the GTP Harness in there, but I just don't see the purpose at the moment.

Has anyone tossed a CompG BIN into run a top swapped engine? L32+3.29's stock, should be dead on. As long as it's not looking for anything fancy from the tap shift / magnasteer / stabilitrak system...

-Rob

[Rico]

Either way he's gonna have to run a wire to the solenoid or use the harness from the comp.

[RivMan]

Top Swapped GT's don't use the solenoid, the just let the manifold vacuum control the valve. No wires required.

-Rob

[SDGTP99]

Wouldnt be too hard to fix up that comp g. Just use parts off your gt. Then you don't have to swap engines, retune, etc etc.

[RivMan]

Engine swap's easy, GT's got a clean title...
Body on the CompG's shot, the whole chassis is twisted, buckled the roof so bad the sunroof popped up. Also it has a Salvage title. Not worth fixing at all.

-Rob

[matt5112]

Either way he's gonna have to run a wire to the solenoid or use the harness from the comp.

No, he wont.

You can simply just disable traction control in the BIN. Or setup that "auto off" function.

Top Swapped GT's don't use the solenoid, the just let the manifold vacuum control the valve. No wires required.

-Rob

Yes, you can.

But you don't need to.

Depends if you want traction control to work or not.

[RivMan]

Yeah, not at all worried about TCS. It still has a big effect without being able to dump boost. Normally the first thing I turn off anyways.

My Riviera had the BBV completely removed, and the bypass port welded over. It worked great daily driving, instant boost. Had to run a bit more pump shot on tip-in to combat KR, but the end result was well worth it.

-Rob

[matt5112]

What?

Why would you do that?

It'd cost you fuel economy.

Add a cam, and now you have retarded blower surge.

[RivMan]

It had the biggest cam and most aggressive heads available back in the day. Fuel was $1.10 a gallon, and economy wasn't really an issue!

-Rob

[RivMan]

A little bit of progress this past weekend. I still don't have the cars in the shop, however I did start ordering some parts. I picked up an Engine Gasket kit from ZZP. I'll be swapping the LIM, valve cover, and Oil Pan gaskets for sure, also all the stuff required to get to the LIM. I picked up Aluminum coolant elbows as well.

Is it worth swapping the head gaskets at this point? I've never personally seen a GTP with a blown one, so I'm tempted to just let them be. I don't really plan to move to anything smaller then a 3.4 pulley.

Thanks
-Rob

[matt5112]

ZZP valve cover gaskets dont fit and leak in factory valve covers.

they only work with their metal covers.

I would let the head gaskets be.