you would need the 57mm throttle body and MAF sensor from the 2 liter to run 2 litre cams, and possibly a remap

but if you putting in piper cams it would also be worth putting in the bigger throttle body and MAF sensor and would need a remap to get the most from them, even if its only a generic map

if 2 litre cams area lot cheaper id say go for them and youll be looking at 135-140bhp on those cams with the remap, but im unsure of the power pipers will give you, maybe the power increase of them out weighs the price!?