ok well i would like to start by asking if there is anyone out there that make any type of roll bar setup for 91 vr4's. also will a dejon powerhouse upper and lower ic piping work for the vr4 engine bay?, i wasnt sure but i figured it would i just wanted to ask before i got myself in really deep,and also i was wondering what a good and farily easy to use tunning software would be, i have somewhat looked into ecmlink but i dont fell like its the right way to go