When reducing the CR to boost friendly 8.5:1 or 8.0:1 (KA) which

is more likely to perform better? Pro's & Con's

 

The 8.5:1 compression ratio will yield more power at less psi, but does not have the extreme psi capability of the 8.0:1 compression ratio. It all depends on how high you want to crank the boost. 8.5:1 should be good for about 350-375rwhp, maybe more. Do some research and see which is best for your application.