Florida Trail Riders will require me to install a spark arrestor on my scoot to race next year.I'm perfectly happy with my YZ's power and was not planning on an exhaust purchase.Which one should I get? Can I use my stock head pipe and just buy the can? I've heard the power gains can be worth the bucks-should I feel lucky to have the excuse and get a whole system? The bike is used for Hares, Moto and fun riding-I would prefer enhancement on bottom to mid. Will I have to rejet? I know this is an old subject but the magazine tests are Moto oriented and not much help-Anyone have a Pro Circuit T-4? Which end cap? How about the FMF? Are they really THAT loud? THANKS!!!!!!!