See here's another problem, grades of gas. My dad's been in the oil business for some 30 years now and knows all about everything - he explained to me, in a high compression car such as i'm building, don't go to stations such as Racetrack or the other discount stations, as they don't have their own refineries, they basically grab all the junk from other companies, mix it together and there's your gas - you'll have high risk of grenading that motor especially on boost or nitrous. Go with a high quality gasoline, such as Chevron, and use 92 octane if its available to you, not 91. Ever notice how the cheaper brands premium is always a point lower than the higher quality gas? With 92 octane, everyone is right, you CAN run 11:1, I would never go higher than 11:1 on a pump gas motor, but theres several things that affect cylinder pressures - your carb is one of them, and your cam is another. The more overlap, the more compression that bleeds off. I've known people in ice cold weather to have pinging problems with 10.8:1 using the largest Comp Cams Nitrous series cam, so just because its large doesnt mean it bleeds off alotta the cylinder pressure, so do your research on this one.