Weights from Motor City website:

86/87 Sport - 2700lbs
88 GTU - 2720lbs
89 GTUs - 2725lbs

The dash in the s5 weighs about 35 lbs more than the s4. The early SE models, the GTUs, and the Sport models generally had aluminum hoods. Sport, 88 GTU and s5 GTUs all had big brakes and hard suspension.

My preference for autox car? GTUs. Aside from that the 88 GTU and the Sport would be a close second.

The ultimate IT car, in my opinion would be the Sport body with the GTUs driveline. Why?
- no sunroof
- manual steering(88 GTU has power)
- manual windows
- preferred aero package

Hope this helps in the information arena.

db

 

There ya go, that's one thing you can do. Get the best possible starting combination and then swap out parts from other cars.

I have a sunroof and the thing is a pain in the *** for helments. I just need an extra 1/2 an inch. It just talked a little getting used to. I like the sunroof though.

 

And the S4 base weighs just 2625. Brakes and LSD are important and the decision would be hard to make. But if your car weighs less it doesnt need as big of brakes to stop it.

The 4.33 gearing on the GTUs would really help out on an auto-x course, especially with the n/as lacking midrange power.

 

yea, i agree that a LSD is imporant (look at sig for current car im racing) but is there a way to turn off the anti-lock braking? that would help in a few turns ive been in... Thanks for all the advice, now the fun part, finding a s5 gtu...

Snake Eyes<l><l>

 

Yes you can remove the ABS.

 

Great discussion. Autox seems to be more about driver skill than equipment, and race tires seem to be the biggest factor in equipment. That said, a light car seems to be the third most important factor judging by who I have seen win the last autox I was at. Every top placer had slicks and some had no interior.

So I would guess any FC on the light side with race rubber and an experience driver (who has tuned the suspension) would be a great autox platform. I doubt the different models would mean much, nor would the brakes. The LSD would probably help a little and be worth swapping into a car w/o one.

I've got an 87 base w/ aluminum hood, no sunroof, serious weight reduction, race tires on separate wheels, aftermarket suspension and soon to have an LSD. I can live with it

 

There are alot of good ideas being thrown around here but there is also some bad info too in terms of which cars had which equipment. Here are my choices for running legally in the stock class:

88 GTU
Good:
About 2700 lbs, AL hood, power steering, LSD if no sunroof, big brakes, stiff suspension, TII seats
Bad: Nothing

86-87 Sport
Good:
About 2700 lbs or less, available with no sunroof, big brakes, stiff suspension, some have AL hood, available with power steering, TII seats (I know Icemark will dispute this :-)
Bad:
Open differential
PS may not be found with AL hood

89-90 GTUs
Good:
About 2775lbs, 4.30 rear gear, TII seats, AL hood, no sunroof, big brakes, stiff suspension, power steering, more engine power and extra 1000 RPM
Bad: ??? Maybe 16" wheels

For stock class autocross, you can change the shocks and the front sway bar, but the biggest thing is that you can run any tire on the stock size wheels so most guys run 205/55/15 or 205/50/15 on the stock wheels instead of the 205/60/15. This will effectively give you the 4.30 on the 86-88 cars and will open up a world of competition tire choices. Also, with the low torque of the car and with competition tires who knows if you really need an LSD???? Power steering is definately necessary because of the much faster ratio plus the speed that you will be able to turn the wheel. Cars with the vehicle speed sensing PS (all 86-88 cars) will have the fastest ratio but less steering feel than an 89-90 GTUs with RPM variable steering which has a slower ratio but more feel.

 

I disagree with wanting to run PS. When I first got my car it had a manual rack and I didnt like it much, but now I wouldnt trade it for the world. Its quick and responsive, and it weighs alittle less and frees up a few hp. The only bad thing about it is if you are stopped or going slow it is hard to move.

 

Well, I can't argue your experience but Grassroots Motorsports magazine considered power steering a must for autocross when they tested the brand new FC in 85/86. The only question they had was whether to go with the GXL for the LSD or the Sport for the lighter weight by about 80 lbs. They didn't come up with an answer at that point.

 

S5 GTUs.
why?
-LSD with 4:30 ratio, you needed, in tight turns to get out of the hole.
-16X7 wheel size=215/40/16 Hoosier=best traction, lower CG,and best final gear ratio you can get legally.
-less than 50 lb of weight difference
-prefered P/S with the same quick ratio
-no sunroof
-8000 rpm redline, no need for 3rd gear in some of the faster courses
-14 more HP

why not?
some GTUS came with A/C from factory.

if you are serious, you need to read the SCCA rule book first, maybe that will influence you decision.
anyway,
good luck to you.

cheers

 

I know you are just quoting websites, but all the Sports w/o sunroof I ever saw were only 2623 lbs (according to the window stickers) and all the GTUs models were 2780 lbs.

 

yep, the Sports were alot lighter 2623 w/o sunroof for a California spec one, and the seats were standard seats not Turbo seats.

BTW, the 88 GTU came with a LSD regardless of sunroof or not, its just very rare to find a 88 GTU without a sunroof.

Quote:

89-90 GTUs
Good:
About 2775lbs, 4.30 rear gear, TII seats, AL hood, no sunroof, big brakes, stiff suspension, power steering, more engine power and extra 1000 RPM
Bad: ??? Maybe 16" wheels

 

Yo,


I've weighed my 1989 GTUs at the track, I think it was something like 2710lbs....but who knows how accurate the scale was.

I think the 4.30 rear end is what is going to make the GTUs the best autocrosser. Given the lack of low end torque on a NA 13B...being up in the powerband is going to make all the difference.

But, I'm biased. *grin* I've actually autocrossed vs. my buddy Paul in his prepped Civic Si. I was on 10 year old suspension and AVS Intermediates and he was on Koni yellows and Falken Azenis (A race tire IMO)...and I was only 1.5-2.5 seconds off his time. I can chalk that up to his tires vs. mine.

I'll have to give it a shot with the 15" A008R's and my new suspension. Win or lose-they'll be some ****-talking after that, let me assure you. *grin*

Kevin
1989 GTUs "No excuses this time!"

 

008Rs? thems ANCIENT! what are they from, like 1982? they've gotta be hard by now R compund tires have a limited number of uses before they lose their stickyness, regardless of tread left.

 

Yo,


They still stick!! They're only from 1998!! *mmph*

I've done two track events on them...they do remarkably well for their vintage.

At least I can chew them up and not my street tires. One day I'll step up and get some Toyo RA-1's...

Kevin
1989 GTUs "A008R's rulez! 0ldSkoolz!"

 

What about a 88 Base with a 91 GXL engine, LSD, brakes and suspension(spelling)?

 

My 86 Sport DOES NOT HAVE TURBO STYLE SEATS!

 

Ice,

I agree that it was only a quote from a website and I had no window sticket to refer to. Been trying to get that one finished up for racing this season. I think it is going to be a good car.

Per the door jamb sticker in the Sport, 2623 is what it is. The GTUs weighs 2510 with 5 gallons of gas and the light wheels with Hoosiers, but there are a few things missing in that one...........

I have another listing of weights done by all the magazines and it is all over the place! I'm glad I didn't quote that one.

db

 

well the problem with the Mag quotes is that they are not consistent.

For example one weighs with a driver and all the fluids (including gas tank) full.

Another weighs the cars with approx. 1/4 tank of gas and no driver or luggage.

Right there you could have a 150-200 lbs difference.

And sometimes a mag will just quote whoever dropped the car off for testing.

So yeah mag weights can be all over the place.

Here is a window sticker from an 87 Sport, granted it does have air and floor mats and cassette... but it gives you a pretty close approx:

 

You guys just made me love my 88 GTU that much more!
Too bad I'm in to draggin! hehehe...
doh!
I would probably love AutoX but I just don't know much about it!

 

I have an 86 sport, they came with 4 pot fronts, 2 pot rears, vented all around

 

oh yeah; another thing that makes the '88 GTU better than the base or GTUs is that it came with the best gripping seats out of the bunch, and they weren't that crappy leather! They are probably the most supportive stock buckets I've sat in to date.

 

I am starting to realize how lucky I am to have found a aluminum hood for my 90 GTU.....I also have another question for you hood guys.....did cars with aluminum hoods have different latch assemblies and hinges....because of the light weight? Just wondering before I unstall it......also did other cars come with that hood beside the GTUs's? As far as the brakes go....I installed the larger TII brakes front and rear.....great upgrade....and they grab like no tomorrow!! Thanks.

 

Some convertables had aluminum hoods. The hood I got from an 88 vert bolted right into my 87 base and the latch fit. It was basically the same as my steel hood but 20 pounds (estimate) lighter.

 

Yea, sorry I was mistaken. Sport models had the 5-lug wheels and larger brakes. They were not available with a LSD though.