yeah I think 24psi is perfect, I tried 28psi and did not like it. Part throttle was awful and it had some surging issues even with my MBC. When I went with a colder plug, preferably NGK BKR7E the surging stopped. I'll tell you though at 28psi the car is a monster At times it would break traction on turns, pretty scary but fun. I have to steal a quote I saw from another AF member, "if it feels like your riding on rails, your going to slow." [8D]