I run my 95 LX in SCCA Street Modified autocross competition. In my last three events I have placed 3rd, 1st and 2nd, with typical competition of Subaru, Mini Cooper S, and Integra GS-R.
Before you change a single part on your car, go to scca.org, download the Solo rulebook and BUILD A CAR TO FIT A CLASS. Nothing will make you uncompetitive faster than using a part that bumps you up to the next class, where you'll have to spend tons of money.
The first class you'll be legal for is F Stock. Stock class is very restrictive, and mods other than shocks, catback, panel air filter, tires, brake pads and a rear sway bar are generally prohibited. This is by far the cheapest (yet slowest) class you can enter. Typical winners in this class include the Mustang Mach 1 and 05 Mustang GT.
Next in terms of cost and performance comes E Street Prepared. This class opens up mods like springs, front sway bar, wheels, brake lines, bushings, strut tower bars, engine programming, seats, intake manifold, headers, torque converter, differential and engine pulleys. Right now, the Camaro SS LS1 is dominating ESP on the national level.
After ESP comes Street Touring X. Here you can change your lower control arms, run any brake setup you like, but wheels are restricted to 8 inches in width and tires are restricted to 245mm. High-flow cats are also allowed. Look for the Subaru Impreza (non-STi) to be the leader in this class. Oh, and the SC MN12 isn't legal in any Street Touring division because of the displacement limit on forced induction cars.
And then we come to Street Modified, my class. I run SM because I began modifying my car before I read the rulebook, and a simple rear gear/driveshaft swap will automatically put you in SM. Why? I don't know. The SCCA unfairly penalizes certain simple mods, in my opinion, but then again the SCCA didn't ask for my opinion. Here's the problem: SM is a wide open--meaning expensive--class to run. If you live in a very active region, your competition will undoubtedly consist of trailered cars no longer driven on the street. Drivetrain options are unlimited, so long as the company that built the car also built the engine block you use. That rule means you'll be up against tons of B16 Hondas, SR20 Nissans and other cars that are lighter and more powerful than ours. Suspension options are also unlimited so long as the attachment points (IE A-arm to frame, shock to A-arm, etc.) are unaltered. So now you have full coilover vehicles to compete against as well. The BMW 3-series typically dominates SM, and if we had any in the region I run they'd be killing me every event.
C Prepared: The SCCA hates shaving weight, so gut your interior and this is where they'll put you. Vehicles in this class are production based, but no longer streetable.
So I can't stress enough to you the importance of picking your class BEFORE you modify your car. Though I'm competitive at a reginal level in my car, I would be flat out destroyed in any divisional event that pays points toward attending the Solo Nats.
But for what it's worth, here's my combination, with a rough price estimate:
255/45R17 Hoosier A6 tires--$900/set
17x8 Voxx Misano wheels--$500/set
04 Cobra front brakes--$350/pair
SCCoA GP front QA1 coilovers--$600/pair
Koni rear shocks--$250/pair
Vogtland rear springs $250/set (all four springs)
1 3/8 rear sway bar--$150
Urethane bushings everywhere they'll fit--$400
JL front STB--N/A, but the KB units are $125 or so
FRPP aluminum rearend with T-lok and 3.73 gears--$600
I won't list the engine mods, which I think are of questionable value.
In other words, I've spent way too much money on the car, and the next step is to swap in an Explorer motor and maybe TKO500 transmission. But in its current state, the car is still very streetable once I put the street wheels and tires back on.
And without a question, the best investment you can make is to buy the best tires allowed in your class (some classes have treadwear restrictions). Changing from a very good set of street Goodyears to race Hoosiers leapfrogged me from mid-pack to contending for the win in my class at every event.
So the short version is this:
1. Read the rule book before you turn a wrench or open your wallet.
2. It's all about the tires. They are without a doubt the best return on your investment.
3. DO NOT swap your rear gears unless you're prepared to have your butt handed to you and/or spend a lot of money.
Last edited by mercutio; 02-06-2007 at 08:55 PM.