Stock cam is chevrolet #3904359 214* 218* .460" .480" 114 LSA
365 mag cam chevrolet #14096209 224* 224* .500" .500" 115.5 LSA

Make a´search on Classifieds,maby someone has a´good used cam for you. (Cheap)

I used that 420HP cam with the old log style manifolds. Never had any trouble. If it is a fairly long drop to to exhaust tips, I would try it in this application. Worst that can happen is you have to change to a smaller cam.