I got a 89 RS with the 305 TBI and i am looking to put the proform 1.6 roller rockers on (Summit PRO-66915). I have read and herd this is the easy bolt on but i herd from some other people that the pushrod may hit inside the head, in the opening it goes through. can anyone shed some light on the subject??

 

You've heard right in both counts.

It's an easy bolt on, but you may need to elongate the pushrod slot. Use a rat tail file in a drill, that'll make short work of it.

 

you said i may? i take it that does not mean for sure, like i may not have to file at all? Can i just get longer pushrods? and if i do have to file down, how much do i have to file down? lot or little?

 

Yea, the factory gives you a bit of extra space, sometimes its enough for 1.6 rockers, sometimes its not.
I had my heads off to port them, so I did it anyway. Another guy on this forum just threw 'em on and drove off. Guess he didn't need to modify it.

Longer pushrods *may* help a tad, but that will just throw off your valvetrain geometry, so I wouldn't use those.

You don't have to file it down much at all, just a tad. Hard to quantify. F-bird'88 has made a few posts on this exact subject, try searching for his posts if you want. Basically, put the rockers on, and as you are adjusting the lash, watch the pushrod, and make sure it doesn't hit the head. If it does, remove the rocker and pushrod, and file it out.