Oscar, The AFR 165cc heads are good performer. I can't say for sure how much more HP or torque they will make over your GT40s but I would expect them to be about 15-20 Hp better. I do know the AFR's made 303hp and 341Torq on a stock 1993 Cobra. given that your 88 GT has a better intake and cam than the Cobra I would expect it do do even better.
Answered by Tommy E.from Hewitt |
Oscar, When you say biggest I am guessing you are meaning valve size and port volume. That being true the AFR 185's would be the biggest I would suggest.