Putting the finishing touches on my 350 build, and am in need of rocker arm advice. I have read the articles on 1.5 / 1.6 ratios, but am looking for info based on a real persons experience. I have installed a 488/ 488 lift cam, new springs, and goodies. The cam manufacturer rates the lift with 1.5 ratio rockers, and I know the 1.6's will increase the lift by a percentage. I have not done anything to the heads to allow them to accept a high lift. My question is..how high can I go without slapping the pistons, or better yet, will using the 1.6 rockers increase the lift to a point that will make the valves tap the pistons. The articles I have browsed put the h.p rise anywhere from 14- 25 hp between the 1.5's and the 1.6's.

I know to look for pushrod bind, spring bind, and retainer clearence. All of that should be ok.

 

Unless you have very high compression, the valves aren't going to hit the pistons.

Spring coil bind and retainer-to-guide/stem seal are the important considerations.