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jrh2009
jrh2009 New Reader
12/20/18 6:37 p.m.

So, a couple of weeks ago, I scratched an itch I've had for years, and picked up a clean 92 Trans Am GTA.

It's in really well maintained, never abused condition, with some tasteful mods. It has the L98 5.7, auto trans, 3.21 rear, WS6 package. Drives nice and tight.

Modifications wise, it already has subframe connectors, square 18x10s with 275/35/18 front and 275/40 rear bfg sport comp 2s, some aftermarket struts, and the Baer 14(?) Inch rotors with c4 Vette calipers. Otherwise, bone stock.

I had been planning to LS swap the car, but upon closer inspection, it's too clean, unmolested, and reliable to change underhood. So I'm leaving the drivetrain alone, aside from cooling or durability upgrades. 

I'm interested in using the car for fun weekend road trips, and maybe 4-5 track days per year. I live not far from Road Atlanta, and AMP, and want to start back frequenting hpde's again.

My two main concerns are, durability, and suspension/chassis improvement. I've already been shopping for camber kits and a strut tower bar, (and have a smaller diameter Momo wheel on the way) but I could use some input from you guys who've been there before.

I want the car to handle neutral, and predictable, and be fun to drive at 8/10ths. I tracked an e36 M3 for years, and am admittedly spoiled, but would like this car to emulate its track manners as much as reasonably possible. I'm more interested in "fun to drive" than trying to set a blistering track record.

 

So for you guys who have tracked these, what are they like on track? Are they prone to understeer? How do they manage heat? I've already noticed it doesn't like stop and go traffic. It won't over heat, but it warms up more than I'm comfortable with when sitting in slow moving traffic. So maybe a bigger radiator/fan combo is in order?

And also, what would you change on it? 

 

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jrh2009
jrh2009 New Reader
12/20/18 6:50 p.m.

jrh2009
jrh2009 New Reader
12/20/18 6:51 p.m.

BoostedBrandon
BoostedBrandon SuperDork
12/20/18 7:02 p.m.

Well done! That thing is mint!

I've never raced mine, but it had the same temperature creep that you described. I eventually replaced most of the cooling system and it got better, but never really went away. I just chalked it up to old car quirks and left it alone.

However I'm sure an all aluminum radiator and dual cooling fans would help. I would ask if the plastic air dam is still under the car, but with the rest of it that cherry I'd imagine it is.

I really need to get mine running. I miss driving it.

jrh2009
jrh2009 New Reader
12/20/18 7:08 p.m.

In reply to BoostedBrandon :

Thanks man, I appreciate it. I looked for years to find the right hardtop GTA. You have to shop the previous owner as much as the car itself to find a good one. As soon as they fall into careless hands, it's all over for a third gen.

Yes, the air dam is there, no damage to the car aside from some dings that will get pdr'd out, and someone lightly tapped something with the front bumper that necessitates a minor repair there. The paint is all original, I'm just going to repaint the front bumper after repairing it.

They are a ton of fun to drive. I can't explain why, but the amount of fun behind the wheel is much greater than the sum of their parts would suggest. 

 

maj75
maj75 HalfDork
12/20/18 7:44 p.m.

Throw a Superbird nose on that Charger and they would be brothers from a different mother.

mr2s2000elise
mr2s2000elise Reader
12/20/18 7:49 p.m.

That is gorgeous. I wouldn't change a thing. 

Dusterbd13-michael
Dusterbd13-michael MegaDork
12/20/18 8:05 p.m.

I love everything about this thread. 

jrh2009
jrh2009 New Reader
12/20/18 8:43 p.m.

Thanks for the kind words guys. I'm in love with this car. Don't worry, asthetically I'm leaving it totally as is. It's gorgeous in person, I don't want to mess with a good thing.

I have some minor interior upgrades on the way. Im replacing the original air bag wheel with a Momo "Race" wheel with a shallow hub mount to keep the wheel in the same location depth wise. I also have ordered alcantera headliner fabric in the original color to replace the original gm fabric. The original headliner is still there (amazingly), but suede will be a nice, subtle upgrade.  

 Hawk's has reproduction seat covers, I'll be ordering a set of them. After that, the interior is practically mint. It's nice and tight with no rattles.

I'm really interested in chassis stiffening, and handling upgrades. I really don't want to change the appearance of the car, Its very tasteful at the moment, and I want to keep it that way. It's nice to see a third gen that has avoided the usual hacking.

I'll post more gratuitous pics!

jrh2009
jrh2009 New Reader
12/20/18 8:49 p.m.

jrh2009
jrh2009 New Reader
12/20/18 8:52 p.m.

Dusterbd13-michael
Dusterbd13-michael MegaDork
12/20/18 9:04 p.m.

Ported runners and plenum and maf picked up a bunch of power on the l98 vette we had.

Id think a bolt in 4 point roll bar, triangulated strut tower brace, and solid hatch bushings (dont know if they exist) would make the car as stiff as could be expected without a full cage or seam welding. 

Dusterbd13-michael
Dusterbd13-michael MegaDork
12/20/18 9:06 p.m.

Oh, are the frame connectors bolt in or weld in?

I know theres plenty of tube suspension and crossmember options. May be those manufacturers have some chassis bracing options that can be recreated in your own shop. Like frog arms on the miata.

jrh2009
jrh2009 New Reader
12/20/18 9:15 p.m.

It has proper weld in connectors. They are tubular, and welded on each end. Don't know the brand, but they appear to be very solid.

Gearheadotaku
Gearheadotaku UltimaDork
12/20/18 9:21 p.m.

 

 That is a great GTA!  What kind of wheels are those?

The front brake kit you have uses what I believe are the same calipers as the C4 Corvette so pads choices are plentiful.

For cooling, Champion radiator has  direct fit aluminum units that won't break the bank. You can get them through Summit racing and Jegs. You already have dual fans but not much shrouding. Get a fan set from a Gen 4 Camaro 98 or newer. (V6 and V8 are the same) They move a ton more air and plug into your existing harness.

The fans on a TPI car are computer controlled vs temp switch alone on a TBI car. You may have to change your fans to run like a TBI car car so they turn on and off together at what ever temp you want. On my '91 L03 car I just put in a lower temp fan switch and it runs way cooler. (fan on at 210 vs 235) I am in need of a bigger radiator and dual fans as I too get pretty warm late in a track session. You would do well to get an external trans cooler too.

Welcome aboard!

jrh2009
jrh2009 New Reader
12/20/18 10:35 p.m.

Good advice guys, that's all really good info. 

The wheels are JNC. They seem to be a cheaper brand, but the fit and finish looks great. I have no complaints with them.

https://jncwheels.com/collections/jnc005

I can't find a triangular strut tower brave that works with the TPI. I can find them for the TBI/carbed engine. The only one I can find for the tpi is the two point brace. Would that be worthwhile still?

 

I've also learned about the "wonderbar", and for the 55 bucks they cost that seems like a no brainier.

Also, just wondering, didn't the C4 L98 Vette use the same engine with aluminum heads? Would the Vette heads bolt on my engine with no other mods? I wouldn't expect any power from them, but weight off the nose would be nice.

And nice ride Gearheadotaku!

 

Daylan C
Daylan C UltraDork
12/20/18 11:00 p.m.

Pretty sure UMI and QA1 both have strut bars that work with TPI. Also I'm taking note on the 4th gen fan idea.

I'm another member with a 3rd gen problem. Here's my '87 GTA hardtop on jackstands. Yours is much nicer.

Dusterbd13-michael
Dusterbd13-michael MegaDork
12/21/18 3:40 a.m.

Yes, l98 vette had aluminium heads.

Check your car for a woberbar. I swear the gta already have one, but it's been a minute and I've slept since then....

81cpcamaro
81cpcamaro Dork
12/21/18 9:53 a.m.

You can use the L98 heads, just know that the center two intake bolts on each side are at a different angle than the iron heads. Not a bit problem but just a heads up.  Lower intake manifold is the biggest bottleneck in the system.

The air cleaner setup is not the best flowing, so any help there will be noticeable.

Joe Gearin
Joe Gearin Associate Publisher
12/21/18 9:55 a.m.

 

Great score!  As a child of the 80's, I've always had a soft-spot for the 82-92 F-Bodies!   For suspension stuff check these guys out:

 

Heidts Performance

Detroit Speed

 

It's pretty amazing what can be done with older cars these days.   I love the resto-mod / pro-touring movement!  

 

 

Patrick
Patrick MegaDork
12/21/18 11:13 a.m.

Undo brake mods, get factory gold mesh wheels, enjoy automotive design perfection 

Daylan C
Daylan C UltraDork
12/21/18 12:23 p.m.
Dusterbd13-michael said:

Yes, l98 vette had aluminium heads.

Check your car for a woberbar. I swear the gta already have one, but it's been a minute and I've slept since then....

My gta doesn't have one, his is newer though so it might.

jrh2009
jrh2009 New Reader
12/22/18 9:27 p.m.

Thanks for the input guys, it's really helpful. I haven't gotten to check underneath for the wonderbar yet.

I was productive  today though, and replaced the original headliner with alcantera. I'll post pics, I'm very happy with the outcome.

 

heres the after.

jrh2009
jrh2009 New Reader
12/22/18 9:32 p.m.

And here is before.

jrh2009
jrh2009 New Reader
12/22/18 9:53 p.m.

Right before removing the old stuff.

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