I've got a friend with a Cobalt SS. When I was stage 2 and he had an intake and catback I could slowly pull away from him. Seemed I could pull better the faster we went too (strange for an awd car). Now he's got the GM stage 2 (computer and smaller pulley I think) and has also changed exhausts. From a 60mph roll we were dead even up to 80 then he started pulling on me. By 100 he had 1-2 cars lenghts on me. However, now that I've got the VF-39 on, his days are numbered!