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2002 Grand Prix tear down/build

Vilemods

Vilemods

New member
This is going to be a bit of a log for my project donor car tear down and 3.8L engine build. I am also going to start a sale thread for parts that I pull so if you see something you want you can either ask over there or PM me.


So I came across this 2002 GP GTP 40th Anniversary on craigslist for a price I couldn't refuse.

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I'm going for a turbo build on the engine and thought I was getting a SC 3.8L since this was a GTP but this car seemed to have a really hard past (I even found court papers about the original owner having to attend AA) and I don't have any of the cars records other then the title. Even if it didn't have a SC I was going down to the bare block anyway to put in new pistons/fresh bore/deck the block and heads. I also don't feel bad doing a SC to turbo setup since I'd hate to gut the SC.



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The interior was in really bad shape. I think that the rear passenger window was rolled down so it had maybe 2 years worth of rain and sun.....lots of sun since I'm in San Diego. There's still some decent salvageable parts from the dash and sunroof.



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Looked to be a factory NA car anyway, the badges on the doors would be different on a S/C car and the VIN number would show the engine option.

The hood/spoiler and roof rails are worth the most money.
 
Hope you have deep pockets to get that 3800 rebuilt right or you could likely have a ~500mi. motor. You'd likely be $$ ahead to just turbo it as is along with the supporting mods assuming it is running good now. Just my .02 though.

The interior looks to be an easy fix. I'd be willing to bet that with the carpet pulled and a good Folex treatment to it, it would look good and save on finding a replacement. Let it dry in the sun and slap it back in.

The seats don't look too bad. Clean off the grime and give it some Lexol on the tops of the seats and see what happens. May actually come back more than you think. My 06 GXP seats looked like that from the JY. They cleaned up really well with some scrubbing and some conditioning.

Sucks that the sun baked the clear off of it. Give it a bath and see what it looks like. Worst case you can try and find front/rear bumpers from another Anni. Ed. to replace those. The hood is likely be harder to find tho.
 
@Fivefingerdeathpunch I was actually wondering what the VIN code was for the engines. I tried doing some diggin for it but turned up nothing on the few things I looked at and gave up. Most of the VIN stuff I was finding was on older GPs. I couldn't find any images on a google search to define the differences between the NA and GTP for the 40th/A.


@FordMan77 The engine has a blown head gasket that I know of already and I have a feeling that water has been sitting in the cylinders since it was parked. I've done engine machining at my local college and have bored and decked blocks before, resurfaced heads with 3 angle valve jobs, etc. etc. so the turbo build was something I intended on spending some time and a little money on as an ongoing project. The interior was pretty nasty. EVERYTHING was sticky, smelled of cigarettes and mold. Was actually surprised I didn't find a dead animal in there. The only down side with the seats is the leather is cracking from baking in the sun and stitching on almost all the seats started to come undone so there are holes here and there. I've seen some pretty good restoring before on interiors like that but a lot of the plastics in the center console are total trash and just fell apart when I tried to remove them. Not to mention whoever had it before me trashed things like the trunk lock by drilling it out (no idea why), I only wanted the motor and trans really as donors for later projects anyway which is why I was going to pass on whatever parts were good in the car to guys on the forum or local club (if there's one here in San Diego).
 
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When you tear it down.. do a good job of looking at the plastic upper intake right where the stovepipe for the EGR goes through. A head gasket isn't very common on a 3800, a misdiagnosis by someone not knowing about the cracks that occur in the plastic manifold allowing coolant to fill the lower intake and cylinders is usually the culprit.
 
@Fivefingerdeathpunch Awesome, looks like it's a NA car then. Glad to know I wasn't crazy thinking someone would have swapped the SC to NA.

@BillBoost37 Thanks for the tip, I'll take a look when I get the engine pulled.
 
Vilemods said:
@Fivefingerdeathpunch Awesome, looks like it's a NA car then. Glad to know I wasn't crazy thinking someone would have swapped the SC to NA.

@BillBoost37 Thanks for the tip, I'll take a look when I get the engine pulled.
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crazy as it sounds, people do put na engines in place of a blown sc engine. hell billboost did it to his regal after the last l67 blew up on him.

my l67 blew up and im running a na bottom end now. cause the l67's are getting hard to find.

you can fine a used na engine with low miles, like 100,000 is really low, for around 300 ish, and just re gasket it and use that. its been proven that the stock bottom end is plenty strong enough, and if or when it blows up, your out 300 bucks, not 2k.
 
and we turbo na cars all the time. im running 12 psi on a l36 na block from 1996. its got like 110,000 on it. i must have 20 plus 1/4 mile passes on it too.

its a huge time and cash savings to just pop in a used block, work your heads, port em even, re gasket everything. then put a metal l26 upper intake with a North star tb on it and turbo that muther lol

while its out the car and stripped down be good time to cam it too.
 


Definitely following! Great find.

From first hand experience, this engine can definitely be rebuilt, but you definitely need to take more care than others to build properly. The big kicker is that almost all the bolts are torque to yield all the way from the mains, crank, cam, balancer, thrust plate, heads, side mains, connecting rods, and rockers. If you go with arp for mains, a main line hone is a MUST.

I don't mean to toot my own horn, but I'm the only one I've heard of with a 3800 rebuild running strong over 10,000 miles so if you need any advice, I'm always here! Also, you might ask selliott for a pointer or two since he has a 500+hp turbo gp.

Can't wait to see the results!
 
@Scottydoggs Yep, was kinda my plan, I haven't been following what the GP crowd was doing since I got rid of my 96' but figured someone had started running turbos. I was reading in one of the other threads about the Northstar TB conversion but didn't dig to deep since it will be a while before I get that far but I already started keeping an eye out for them. I've got a decent size pick'n pull on the south side of SD that I might go scope out for some parts like the alum intake upper/lower and TB.

@wstefan20 Glad to know some guys have gone to the wild side for builds that can pass down the knowledge. I'm not trying to break records but I wanted a nice solid turbo setup to push around the same, or a little more, HP as a tuned SC. Thanks for the info on the main line, I'll have to keep that in mind when ordering the hardware and getting work done to the block. I will definitely be picking your brain later one in the future.


So far I don't have a lot for photos on what I've been doing but I've already got the car up on jack-stands and gonna drain out the fluids tomorrow. Still pulling bits off the car here and there and I'm struggling to get the drivers seat out since the battery for the car is trash and of course the seat was put all the way back on the rails. The place I'm working on it has some jump assist boxes that will hopefully give me the power to move the seat forward so I can take the bolts out. If it doesn't work I have some ideas on how to get it out without destroying anything. I also need to drain the gas tank and I'm hoping that whoever had it before me didn't have a full tank when it was parked. I'll try to get some pics of where I'm at on it and post them up later tomorrow.
 
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There's plenty that have had these engines built. The key here is if you don't do it right it usually goes south. Do it right and like anything.. it'll be good
 
So update time! I had some good time to work on the car the past couple days and made a bit more progress. First was tackling the drivers seat, luckily the jump boxes just needed a charge so I was able to move it forward and pull the bolts out finally.


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Next I moved on to putting the car on jack stands, pulling the front facia off, and draining the fluids.


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When I went to drain the radiator not a whole lot came out, I mean like almost nothing, and what did come out was just plain rusty water.


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I found where all the fluid was when pure water started to flow out of the oil pan and then finally turned into that nasty sludge of oil. So I'm pretty sure this car has a blown head gasket, or potentially something worse.


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I pulled the thermostat housing off and to my surprise and horror there wasn't even a thermostat. I was graced with a ton of crusty oxidized flakes of pure hatred from the previous owner. This definitely doesn't look good and is putting a bit of worry for the state of the block and the heads.


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I'm worried that the previous owner was leaking water into the cylinders from the head gasket and overheated the car so he pulled the thermostat and just kept putting pure water into the rad. I'm pretty sure the engine might be hydro-locked at this point so I'm really going to have to try and work those pistons out. I might have to get the block magnafluxed to see if its got cracks in it as well and check the heads for warpage/cracks. If the block is good I'm for sure gonna have to have it acid dipped. There was so much crude in the cooling lines so I'm sure all the passages are caked. Luckily I'm not out much even if the block and heads are toast since I still have the trans, harness, accessories, cv axles, etc. etc.
 
@Vilemods sounds like a good plan! Once you get those heads off and cleaned, check inbetween the intake and exhaust valves for cracks. You can usually see them with nothing but your eye. I went through three sets of heads before I found one without cracks.

My block and heads were too far gone and I ended up having to pull a junkyard engine to rebuild. No shame in rebuilding that!

Looks like the prior owners really loved this car.... LOL
 


@wstefan20 I've repaired cracks in cast iron heads before when I was taking a engine machining class at my community college and got to magnaflux it as well, fun to play with but like you said most of the time you can just see the crack. They had all the fun toys to play with! If I have to grab more heads and/or block then so be it. It's not a "build" without having a few headaches along the way.
 
@Vilemods Man! I wish I had the equipment you do! I never learned how to weld, so for me, they charge so much to repair heads it's never worth it. Probably paid nearly $1500 in machine shop costs alone total. Sure wish you were closer!
 
@wstefan20 Well that was when I was in school, I don't work at a shop. I went to school for welding/machining and drafting/design with a couple auto classes here and there for fun. I still haven't taken the engine rebuild class since I didn't have an engine to take with me but hopefully I'll still be in SD when I'm ready to start working on this one. The class is like $140 plus lab fees iirc? The place I'm working on the car is an Auto Hobby Shop. Military and their spouses can rent a lot/lift and have a tool room with mechanics looking over your shoulder or help if you need it. They are the coolest places to work on your stuff. Here its always busy too with guys doing things from oil changes to cutting springs, yeah....I watched a guy do that one day for his FRS. What's even better is the shop has classes for the service members to teach them how to properly do things like change out brakes and resurface the rotors. Past couple years they put in some Motorcycle lifts for the bikers on the base. If it wasn't for my wife being in the service I wouldn't have access to this kind of stuff.
 
@Vilemods Wow! That sounds awesome. Sounds like you'll have everything you need! Meanwhile.... I'll be building another engine for my fiero soon and probably spend $2000 more than it'll cost you! :th_laugh-lol3: Can't wait to see your results though. I'm thinking about a diy flowbench this time around... at my current job, I have access to special vacuum equipment and plenty of machinists to help me fashion a bench, but we'll see. There's always not enough time and way to much else to do though.
 
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