We are running 10.5:1 at 8PSI on 93octane plus meth injection and tuned properly. This is as much as I would feel safe running on a stock short block as long as it is tuned properly. I think is is more about the temps than the pressures because the cylinder pressures are directly related to the charge temps. Very important details! This is why we are able to get away with it on our setup. Timing also is just as important. I prefer the higher compression/lower boost over the 8.0-8.5:1 with tons of boost because in the end you are going to end up at the same point but you loose out on lowend,no boost torque and lower rpm torque from the lack of compression. I would not want to sacrificy torque for high peak ponies.