I swapped to the LS7, had to switch from a single bolt cam sprocket to the 3 bolt cam sprocket( about $25 for the sprocket and the 3 bolts new). Prior to putting the cam in I switched over to the PAC 1219 springs(allows up to a .625 lift cam), titanium retainers, new valve-stem seals on intake and exhaust sides, and I also added the Texas speed hardened pushrods in the process. Then I put some new GM MLS head gaskets and torqued everything back down.