all these points are very valid. it takes a lot of r&d before you can get what you're looking for. i read your list of mods, it does sound like your air/fuel ratios are kinda funny. also, you might want a flywheel to go with that clutch, and like everyone else is saying, the exhaust problem. i live in northern virginia and there are a few shops around here. Evolution is one in Chantilly (evolutionautosports.com) and they are very good. Have a lot of awards and very knowledgable. There's Autothority, but they mainly deal with European cars. Car Trenz (now under new management - called Alpha Omega Motorsports) are good also. Good prices on JDM parts. Check these out. Hope it helps.

Hope everything goes well. Good luck.