You can get a cat-back, but nothing more on the exhaust.
If I were to do everything possible within the rules of G Stock for my SVTF, this would be it.
K&N Air Filter
Lightweight SSR 17x7.5" Rims & Titanium Lug Nuts (drop 37lbs of unsprung weight!)
Kumho Victoracers (shaved & heat-cycled)
Koni 2-way adjustable dambers
HIA cat-back exhaust (probably wouldn't really, not much advantage)
Lightweight Oddessy or Optima battery (dropping 30lbs out of the nose is a good thing!)
Hawk HPS brake pads
Full roll cage (strangely enough, they do this to allow the road racers to come AutoX without being totally screwed for classing)
Alignment (can't do much, maybe squeeze a little caster out of it and some front toe-out)
And that's pretty much everything that I could do in the stock class. Would make a VERY fine little racer, and one that could regularly beat Touring-Class STis as it's on R-comps.
Stock class really isn't that slow, especially at the regional level. At the final race, a Mini Coopper S on slicks and Konis (with a 2nd year driver) was within 2 seconds of Chuck Hemmingson in his Subaru STi on slicks. Chuck had just come back from winning the national Touring 2 road race championships and was on the cover of a magazine or two. That same Mini destroyed a couple full-race C3 Vettes, M3s, Evos, etc etc, and had the 3rd fastest time of the day. So don't be in this huge rush to get out of stock class.
Don't waste another minute waiting on parts, or anything else. Just get out there and start racing! You will suck at first, and you will be slower than many other cars, but the only thing you will regret is not starting earlier...
Last edited by Carrera26; 12-29-2005 at 08:37 AM.