Well, everybody has an opinion so here's mine: they will be fine IF you do not go beyond 8 p.s.i. AND you install a boost retard unit AND you run 91 or higher octane. I've met several people with stock, (hyper pistons), 87-93 Mustangs and blowers running 8-9 p.s.i., boost retards, and hi octane that have engines that are runnig and racing with over 100,000 miles on them. Your air/ feul ratio is CRITICAL. I would not floor it until all of this is installed and your on a chassis dyno with a good wide band O2 sensor to check your ratio.