High Compression, Carb.....and Pump Gas

[SDMAN]

Stick with <11:1, and 10.5-10.75 is the sweet spot for premium pump swill and aluminum heads. You only gain ~4% HP per full point of compression, so the very small power gain isnt worth the considerable (and ultimately expensive) risk. Even at the 10.5-10.75 ratio, you need to get all the details handled.