Mitch R's TGP Restoration Thread Updated 9-18-18

[Dark Ride]

Damn good progress. I admire your drive to fix one so far gone.

 

Changed thread title for you.

 

Thank you!

[Dark Ride]

Update:

 

Here is some stuff I got done about a month ago, just got lazy about posting.

 

I met up with danny and we decided it would be easier to swap engines without that annoying radiator support in the way so we cut it out. Should be much easier. You can also see that I used sound deadening material on the front of the firewall to replace the old rubber stuff that used to be there.

 

 

Here is the support put back in, I wish I would've taken more pictures, it really doesn't do the work justice. Danny did an incredible job.

 

Here is the new motor going in.

 

TGP + L36 =

 

After I got everything re-connected and buttoned up, fluids filled, I turned it over for the first time and ...

 

 

turn, and turn, and turn, no fire.

 

Insert 15 minutes of sadness here.

 

Then it dawned on me, that while I had wired the harness for the passkey module, I hadn't actually plugged it in yet. Lo and behold after plugging it in the engine fired right up. But it idled like complete crap. Turns out that somehow during the swap the brake booster went to hell and started leaking. So once I disconnected that it ran like a charm.

 

So I kept my promise of having a motor in by winter, unfortunatly within 15 minutes of having it idling right and backed it out of my garage for the first time on its own power, it puked. Turns out the brand new walbro pump I installed was faulty and after pushing it back into the garage that is where it rests.

 

So with that my goal for this winter is to relocate the battery to the trunk, drop the tank and replace the fuel pump, and re-install the rear-bumper with new crash bar.

[Addicted to eaton]

that sucks!

[supertrick_05]

Damn dude, this is an awesome restoration/build thread! Your car is going to be amazing when it's done, I can already tell that. Not sure if I missed it in the thread or not, but what plans do you have for the 3800? Turbo?

[Dark Ride]

Wow.  I've been working off and on on car this car since then, but I have to say it was really cool reading this thread and seeing my own progress and remembering how far it's come.  I've been starting to burn out on this again as sometimes it just seems like the car itself is against me, everything lately has been 2 steps forward 1 step back.  I thought I would post an update after all this time and keep this updated again as I'm definitely closer than I have ever been with this.

So let's see:

I got the new pump put in.  Got the windshield replaced.  Relocated the battery to the trunk.  Got it drive-able.  Installed a new Pioneer deck with my amp and 6x9s from my original Grand Prix.  This car is also partially a tribute car to my first car which was also a 90 Grand Prix although it was just a base LE.  Then it sat for a while.  About two years ago I bought a used Cartuning turbo kit from Bake82 and have been slowly installing the kit into my car.  I got all the oil lines installed as well as the wastegate perch & wastegate.  I also installed a front plog and an HV3 insert as well as L67 injectors.  After that is when the trouble started.  I knew that it wouldn't be bolt on given the differences between 1st and 2nd gen but it was quite an undertaking.  The kit came with a Garret T04B turbo with an on-center housing.  The turbo itself needed a rebuild and I decided I wanted to upgrade to the PT61 turbo.  Unfortunately, that turbo is no longer available as it seems Precision no longer makes an on-center housing(at least for that application).  I ultimately decided to use the Precision 6262 which actually worked better with its tangential housing.  The biggest issue I had was getting around the master cylinder as the original kit had the downpipe going right through it.  The 6262 helped in this regard as it dropped the turbo outlet down.  I ended up modifying the crossover and bit and used only a small section of the CT downpipe, adding mandrel bends to create a custom downpipe which ended up looking like this:

I also replaced the brake booster with one from a 02 Monte Carlo.  I also got my wideband installed.

Interior is still in pieces, hoping to at least get the dash put back together very soon:

Here is the motor currently, I actually had it assembled and running but had to take it back apart as the downpipe wasn't sealing properly on the turbo.

Picture of the turbo just cuz I don't think anyone gets sick of looking at them

 

So my next steps are getting the downpipe fixed, and getting this put back together again so i can at least move it.  Then I'm going to see about getting some of the bodywork done, there is some decent rust in front of the rear wheels that I think may need to be cut out and replaced.

 

Edited September 19, 2018 by Dark Ride

[Imp558]

Isn't there a problem with the plastic plenum and a turbo? It seems like guys do aluminum so I always assumed they flexed too much for boost and leaked.

I don't know for sure.

That car looks really good,  hope you make it to a meet some time.

[Dark Ride]

They aren't ideal.  They can explode if you push too much boost through them.  Most guys seem to be able to run 15 psi before it really becomes a concern.  For now I'm leaving the stock wastegate spring in which limits boost to 9 psi.  The trans is still stock and they can't take much more than that either without upgrading.  My long term plan is once I get it completely put back together, painted, and driven a bit, I'll pull the motor and trans, upgrade the trans with a new input shaft and chain, and put a turbo cam in the engine.  While I have it apart I'll install the newer aluminum uim.  Then I'll crank the boost higher.

[Mach 5]

happy to see this still going. I just noticed the post prior was 7 years ago.

We've (chevy buick dealer) had the stock plastic manis here explode even without boost. as well as leak. just be careful but you already know that. Good turbo for this. nice downpipe

 

-Jarek

[Dark Ride]

8 hours ago, Mach 5 said:

happy to see this still going. I just noticed the post prior was 7 years ago.

We've (chevy buick dealer) had the stock plastic manis here explode even without boost. as well as leak. just be careful but you already know that. Good turbo for this. nice downpipe

 

-Jarek

Yeah, I've seen some where it backfired into the manifold and boom.  Definitely, going to an aluminum one sooner rather than latter.

I actually made some decent progress over the weekend I've got to get posted up.  It's running again.

[Dark Ride]

New lower downpipe:

Upper downpipe installed with heat shields to protect master cylinder and the plastic valve cover (aluminum ones are also in order here)

Turbo installed, I coated the exhaust and center housing with high temp paint to hopefully prevent rust.  We'll see if it holds:

Charge pipes, air filter and oil lines installed.  Need one more t-bolt clamp.

All back together, just need to install that one t-bolt clamp and bleed the brakes.

Intercooler install will be coming this winter hopefully, I'll install the BOV at the same time.  I need to move the car and would also like to get the rust work done soon as well.  I'm not going to be driving it hard until the Intercooler and BOV is done.

Edited October 3, 2018 by Dark Ride

[Leadfoot]

Way to stick with it.  This will be great once its done.  Post a vid when you get it out and run it.

[Dark Ride]

On 10/3/2018 at 3:57 PM, Leadfoot said:

Way to stick with it.  This will be great once its done.  Post a vid when you get it out and run it.

Thanks, I'm really looking forward to it being done.

 

Rust behind the doors in front of the rear wheels...

Does anyone have any experience with rust repair here, is this something they can cut out and weld in a new piece of metal.  It doesn't have to be pretty since I'll cover it up with the ground effects anyway.

[Brodizzle83]

Ha, found your build! Nice car man! As for the rust fix on the rear quarter...cut and weld in a new piece. Just any old sheet metal with the same gauge thickness, then spray it and treat the backside (if you can get to it) with KBS Coating's RustSeal.

Sent from my SM-G955U using Tapatalk

[no1kicker]

This is great.  I've always wanted a 3800 TGP and I was curious how much of the cartuning kit would fit.  Seems like the downpipe was the biggest issue.

[Dark Ride]

Thanks!  Yeah, the downpipe was almost completely custom.  The CT kits have 2 bolt exhaust flanges between the upper and lower downpipe.  I had to use vband as the flange wouldn't fit between the rear exhaust manifold and the firewall, it's a really tight fit.  The gen 2 engine bays these were made for are at least a couple inches wider.  The vband requires a good deal of finesse to get it locked in place.  If anyone ever does this I would absolutely recommend using the vband flanges with the machined male/female design, they were a life saver.

I'm not a body guy unfortunately, so I'll end up having someone fix the rust and paint it.

[Brodizzle83]

Looks like you already repainted the engine bay...that in itself is a huge undertaking and a detail that makes a huge difference.

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[Dark Ride]

Yeah, its pretty easy to do when there is nothing in it

I took it for a drive around the block, it suddenly wants to eat tires, not sure what caused that...lol 

It's definitely fast, and there is very little boost lag, which was what I was going for.  A car that builds boost like a blower but without all the parasitic loss.

[Brodizzle83]

Hell yeah! Did ya tinker with the other car yet? How bad is the trailing arm rust on it?

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[carkhz316]

Back from the dead, haha. Glad to see this thing still going!

[Dark Ride]

12 hours ago, carkhz316 said:

Back from the dead, haha. Glad to see this thing still going!

Yeah, finally running again.  How about you, how's the Monte? 

[carkhz316]

I drove it in and out of the garage once this year. And now it's back in storage for the winter. Sad, I know, haha.

[Dark Ride]

9 hours ago, carkhz316 said:

I drove it in and out of the garage once this year. And now it's back in storage for the winter. Sad, I know, haha.

Yeah, but I can relate, especially with the family.  I have two myself now, and they keep me plenty busy.  At least it stays rust free that way.  My poor GTP has succumbed to the MN winters.  Probably only got a year or two before I start seriously questioning whether I can keep driving it.