Well my buddy bought an 07 z-06 last year. Well he recently added a pro D-1 to it. Well the person who installed it said that 8 pounds of boost would be okay for set up. My buddy is knid of worrined because of the 8 pound and i think 15 degrees of timing. Is he okay or should he be worrined? Please help. I told him that maybe he should keep it at 5 pounds of boost. By the way he made 605 horse to the wheels with this set up. Let me know what you guys think?

I wouldn't run 8lbs on the stock compression ratio. I've talked to a few reputable tuners who agreed that 5 psi is safe and effective on the stock compression, but much more than that is asking for trouble. If he upgraded the pistons and essentially made it a s/c motor, then 8 psi would be no problem.