This is what I am going to be going with for my primarily E85 car. 9.5 is marginal for 91 octane but still doable.

10:1 sounds a little high to me for straight pump gas on a turbo car, but I am no engineer or tuner.

 

Ok so now that 9:1 is the best option what about bore? 86.5mm is stock should i just leave it 86.5mm or over bore? 87mm, 87.5mm,88mm? Is there any real advantage if i over bore, quicker spool?