Hi guys
i just want to get an opinion about X or H pipes
im having a 370z with Legamax HKS Cats with H pipe + FI LTH + Stillen 3rd G CAI
well i feel that im losing power, i mean before installing the stillen and FI, it was faster than now (old mods was HKS legamax, test pipes and takeeda short arm CAI )...
so if i changed the H pipe to X pipe will it differs ?
please HELP