Just for kicks try going down a few teeth at once, all the way to a 8.something and see how the car holds up. There is a middle ground where the car will suck (like between 7 and 8). Then again, the tracks might just be too different or I might be running motors that rev higher with less torque. But I have had good results.
Scotty's track has a straight that is just about as long as ours in Madison. In fact I think his track is about the same length as ours, but about 10 feet deeper in the infield. Could be wrong about that though, I haven't been over there since late September.
Somebody asked about the P2K2, it is closer to the GM3 than to the P2K, I would definitely gear it a couple teeth down from the P2K. You can gear the P2K super tall and it will respond. In a lot of aspects I like the P2K the best, but if you get the Green 3 working just right, I think it's the fastest guy out there right now.