[biketopia]

If you plan to do a cam, you should replace the lifters, and then the heads need to come off. You can do a factory LS9 or LSA cam and some LS7 lifters and pick up like 90hp, plus you can pick up one of those cams for like 90 bucks from your local dealer, or less if you get a used one. The LS's are pretty good about being sealed up, if they don't leak I wouldn't mess with it unless you want to replace the oil pump and timing kit. You need a way to realign the covers if you pull em off just FYI. Either I'd go in and do a cam, lifter, oil pump, valve spring upgrade now, or just let it be and stick with the intake seals and knock sensors. Use GM sensors and replace the under intake harness with GM also. Plenty of people have run into issues using after market there, also you can seal up the rubber with silicone to help keep dirt and water out of the knock sensor wells.