I prefer the American Racing with X pipe. All the data I have seen shows it to be better. You should always go with an X pipe. Go with the 1-7/8 ARH with X them go for the cam. If you can swing it, go for it all at once.

Hey I need your advice... I installed Pulley SLP, Magna flow axual dual compettetion, Carbon Fiber LMR Air intake.. Im planning to installed american racing or kooks .. I dunno which one is better.. should i go with X or with out .. or should i go for cam shift also... I have l99 ..