Hello everyone,

I have a set of chebby 041 heads sitting on top of my 1973 sbc motor. I am thinking of installing some 1.6 rockers on the intake sometime in the near future. Right now the setup is this: 1.5 rollertip rockers, 5/16 pushrods, and guideplates. Here comes the question.... Will I need to drill or have drilled a larger diameter hole in the heads where the pushrod thingys goes through, if I switch to the 1.6 rockers? And to what size should they be drilled to if necessary? I think I could take on a task such as this. It doesnt look to hard. Just want to know if it is needed or recommended. I thank you.