Originally posted by thefrush
I have an SVT Euro that I run 16's on for autocrossing, it is my race wheel/tire set.
Rules are rules. If you want to really 'compete' in GS you must follow them. On the regional circuit, it doesn't matter as much, but nationally you cannot squeeze by with anything. Plus, are you really trying to be super competitive in GS? Because if you are, I would reccomend getting a K&N drop-in, catback exhaust, and some lightweight 17's with race tires before you start getting illegal mods.
Most of my answer right there. If you really want to be fast, spend your money on some R Compound tires instead of that other stuff. Nothing will make even close to as much difference. The second best would be to get some Koni Adjustable dampers, which are stock-class legal.
As for the engine mount and a STS, you really won't be getting much use out of either on course anyway. 90% of the course is between 4K RPM and redline in one gear the entire time. Most of the time, you won't even leave 1st gear, or you'll shift once into 2nd and leave it there. So it's not like either of those will be much of a benefit to you anyway.
Nobody at the regional level is going to care anyway if you want to do those mods, as a noob driver isn't really going to get close to anyone really in competition for points... Besides, I beat 90% of the STS drivers on street tires with no mods, so it's not like STS is some much higher class. In fact, since they are a "street tire" class and can't run R Comps, the good Stock class drivers usually beat them.