to make an NA faster. The $/hp is so high, compared to a TT, and it's a heavy car, so it will never be fast. The 1 piece d.s. is also controversial. My opinion is never buy one unless you use your car for racing only. They vibrate. I say enjoy having a Z and save your money for proper maintenance, or a TT. Also, what's wrong with your clutch fork and O2 sensors?