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Message: <blockquote data-quote="9psi 98" data-source="post: 529394" data-attributes="member: 9429">Which you will totally be able to do. The PI cams I had were not supercharger friendly at all. The duration isn't long enough on the exhaust side so you are losing some of your boost out of the exhaust before it gets a chance to close. Sorry that I took so long to find this thread. You can use an aftermarket cam that has over .500 lift in an NPI head without machining contrary to what a few people might tell you on here. In an NPI head, PTV contact isn't the major issue when installing a cam. The problem is that the valve springs have less room to compress in an NPI head than they do in a PI head. "Coil stack" is not something you want and with a higher lift cam, you are approaching it's limits. I did a lot of research and finally ended up taking my cam covers off and felt around with a feeler gauge just to find out how much space there was in between the coils. A stock PI cam has a .530 lift and that is what I originally had in my NPI heads without any problems. So how can there be a limit at .500 for an NPI head? I currently have CMS Stage 2.5 Blower cams that have are .536/.540 lift, 228/235 .050 duration, 114 LSA installed in my ported NPI heads. Yes, an NPI head can handle a .540 lift and still have some room left....not much though. I used Crower .060 offset retainers just to add a little insurance, but I am 100% sure that I could have gotten away without them. As for degreeing a cam, some people say it's a must and some others don't even bother. The undisputable truth is that the cam has a keyway on it and can only go on one way. As long as you don't let your timing chains jump the gears to throw your timing off, than you are 99% degreed already. Sure, you can get the timing wheels, tear off the front of your engine and do it the "right way" as most everyone puts it, but if there are no machining issues with your cams (usually if you get them from a reputable company there won't be any issues) they are doing exactly what they are supposed to be doing because of the keyway and the already correct timing. Degree them if you want, but I think it's a waste of time if you did a good install and kept things lined up the way they should be. It's always smart to turn your motor over by hand just to make sure everything is not going to collide inside the cylinder anyway.</blockquote>