big call to say how much you take off head.cam size plays a big part/piston to valve/then comp ratio.you need to work the piston to valve clearance (cam should be dialed in first) & comp ratio as it stand now(before anything you done)once you know your clearances then you can machine head to suit higher comp & less piston to valve, if it allows you. this is a starting point. do you have the cam specs card,.

hey guys i have a 1000 ute and my a12 is a tiny bit smokey. still runs good but i know its time to start getting somthing different so i recently bought an a14. its a A14 with hi comp pistons. not crazy hi comp they are the ones bought of bige it also has a mild cam from stewert wilkins motorsport. the mild cam is a 37/70. also i have a H75 head wich has double valve springs and standard ports and valves and a pulsar electronic dizzy converted for a series. now i think im after a single side draught webber or dellorto, manifold and extractors. when it comes to setting up the webber what chokes, and jets do i need to use? also does anybody know how much i can shave my head so the valves dont hit the pistons but i also want to use just premium unleaded so comp cant be too high. is there anything i havnt thought of yet?