oh for putting 500hp down get rid of the obx's and the 18's get some wide 15" rims and get atleast nitto 555r dr's or some m/t et street's. those bars don't help for shit when lauching your car just get a nice set of fully threaded coilovers, and the whole polyurathane bushing kit. look and see if z10 makes a raduis rod kit for your car that will help alot.

so raduis rod's
full coilover's
and bushing kit
and some sticky ass tires
and fill in your motor mounts