With the stock turbo, there in no sense revving beyond the factory redline, because you don't make any more power. With a the FP68 turbo and 93 octane you can run at least 25psi to 8000rpm, but I would not go over 7200 myself with factory internals. Forces on the rods increase with the square of rpm. At some point the valves will float. The cost to run 8000rpm safely is high.