The silver rocker is an older Summit roller rocker. The blue one is a brand new version of the same thing.
They're for 3/8" stud SBC with stock 5/16" pushrods.
My problem is the press in fulcrum (where the top of the pushrods contacts the rocker) fits the pushrod as you would expect on the silver one, but the blue one has a larger diameter, as if it's designed for a larger pushrod.
One of the comments under the listing for the part says -
"I had bought a set of 16 of these rocker arms last year but when I went to install them, one was built with a 7/16 fulcrum instead of a 3/8 fulcrum. Measure and make sure that yours are built correctly".
Here's the listing
So my question is...by looking at the two rockers does the blue rocker look like the part that contacts the pushrod look too big for a stock pushrod, it does to me, and it doesn't fit snug like the silver one. But with out seeing more blue ones I don't know of it's wrong or just the design...
I'm contacting Summit now as well.