hi all. just wonderd if any1 could tell me the best pistons to use on a 2.1 zvh to get the right compresion ratio?

i wanna use forged 1's wit steel rods for strengh etc an to run higher boost levels. all i can find is zetec turbo but im told this will make my compresion ratio too high an make a laggy engine wich i dnt want. quick link forwhat ive seen

http://cgi.ebay.co.uk/2-0-2-1-ZVH-8v...item29eceddb2c

theese are lited for both so would they supply the right 1's for zvh or they be the same? any help would be great cheers