The cam, as pointed out, is different from 325 hp and 350 hp. Essentially, that is the only difference between the 2 engines. I’d try a good reputable cam grinder like Bullit Cams. Their cores are better. I’d be very concerned about todays Chinese cores. I think with some hunting a nos GM cam could be sourced. Calcimine is good oil. Shaeffer and Brad Penn are good oils, as well.