As far as detonation goes, I really agree with K_gpz on this. The drop from 8.8:1 down to 8:1 will keep the motor farther from detonation under boost. I have looked very closely at the cars running huge amounts of boost and high static compression ratios and in almost every case they are either running race fuel, very little timing or both. Very often they also have engines that were designed from the factory with forced induction.
Another thing to consider is that there is no knock sensor out there that will work with the 12 valve Alfa so it's really important to avoid knock in the first place. I am a strong advocate of water injection. If your engine management system has provisions for knock control it can be connected to the water injection system so that when the water level is low it retards the timing. (I have not actually done this, I go another route)
The logic behind the 8.8:1 compression ratio I designed is this:
1. We can get in enough boost to blow the transaxle with these pistons so we don't need any lower. (original SuperVerde ran 7.5psi, no intercooler, no water injection, L-Jet and 89 (r+m/2) pump gasoline. Not even premium fuel!)
2. With the supercharger removed or when off boost, power is very close to stock (drag race verified!). The off boost issue is important because I don't want the supercharger to engage every time I encounter an minor uphill section of the road. With a turbo, you have essentially the same issue.
With all that said, I would really be uncomfy with 8.8:1 and 22 pounds of boost on an Alfa V6 with pump gasoline.
Greg Gordon,
www.hiperformancestore.com