I suggest you get it to a dyno before you do too much else, because what you're saying here is contradictory. Unless your cam was way out of whack when you started, higher cylinder pressures should mean less top end.
Did you degree the cam when you got it, or did you just throw it in there? To get the most from any cam it needs to be degreed, BRAAP was nice enough to do a good writeup on how to do that:
http://forums.hybridz.org/showthread.php?t=111523
Timing the cam is different than timing the ignition. On the ignition, the earlier the spark happens the more time the engine has to burn the mixture, so you want more advanced spark timing at high rpms (up to a point usually in the mid 30's degrees BTDC). The cam is opposite. I tried to explain why this is, and couldn't. I looked a bit online and couldn't find a succinct explanation.
Check the bottom of this page:
http://www.webcamshafts.com/cam_glossary.html