i was wondering i have a 90 integra and i have a after market tack that says the car will rev to 8,000 or 9,000 rpm but it wont cuzz its set stock at i think 6 or 7,000rpm be for it hits the rev limiter i dont want to float a valve? so how much would it cost to put stonger valve springs in so i could rev out to 8,000?