Phil, didn't you say that you're running the Isky 301333? I know the LSA is 112; however, I've not seen the cam card. Overlap? Does your 55 Tbird have power brakes? Someone I know is building a 312/w target of 300 HP. I told him he'll probably need 228 degrees duration @ .050 to get there/w G heads, but he has power brakes. I'm thinking the 112 LSA of the 301333 will provide enough vacuum for his brakes.