ok thanks....i knew about doing it that way, but just wanted to see if anyone done this before?

I think the front cover will have to be cut also??? am i rite in sayin this???

Do what engine builders do. Mock the engine up, and turn it over with some modeller's clay on the piston. I read some where that you should have 100 thou clearance on a manual, and 90 thou on an auto.
Bear in mind too, that when adjustments are made to the cam timing, the clearance can get smaller. The biggie is the exhuast valve. It is being chased by the piston as it closes, on the exhaust stroke.

Im going to get my L16 block and L20B head cut Monday at 1mm each to raise the compression to around 9.2-9.5:1. Does anyone have an idea if the valves would hit the pistons or how deep valve cut outs would be in the pistons....I'm using a standard cam at the moment..