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

 

I used vauxhall c20xe pistons in one of our cars, they require the block boring to 86mm iirc, plus a little honing of the zetec little end to allow the gudeon pin to fit nicely, they sit 3mm lower in the block on tdc than the standard pistons. The engine i did also has had a kent cam, super chip, still on mfi managment using a bigger turbo with .48 exhaust housing running just over a bar of boost iirc and that made 197bhp with 239ftlb of torque so is plenty good enough really, hope that info helps.

 

sorry pal, but you really are down on power with a BAR of boost, i'd say the mfi needed sorting out really badly.
you ideally wan tto aim for 8.5:1 for getting good economy and response, but head down to 8:1 for getting more boost.
if you're going for big big power, then go as low as 7.5:1, i wouldn't do this unless your power is over 400bhp though as it'll be less efficient on lower boost.

 

just to add, you can always get the block decked to raise the compression back up a little