If your mtr is 10 & a half or less comp ratio,don`t run over 34 degrees of total advance,it won`t help you.Also if your rocker arms are adjustable,back them off a 1/4 turn at a time as they could be a little tight.Just had the same problem on a 283 chevy w/ same carb,backing the valves off made a big diff,it had a cam comparable to yours.
