Clearly they don't! Stop selling us chevy parts for our BBF!

 

If you watch in the video you can see how the steel rocker is waaay too far out on the valve stem.

 

Where the roller rides on the valve stem makes no difference what so ever as long as it doesn't run off of the edge and the rocker arm produces the correct motion.

 

There are alot of “BBC” stuff that fits Ford motors. the main cap bolts for a 351M/400 are the same as a BBC. It could have been your aftermarket stuff that made the difference in this situation though its hard to say for sure.

 

Sure but then why would the cast roller rockers fit mint? I'm confident the steel rockers would have come off the edge of the valve... it was that bad. Plus you can't even tighten the GD nut down.

 

Those might be for Cobra Jet heads? Guide plates and screw in studs or not
Either way, you need longer pushrods to use those on your heads
Your fulcrum is way down on the stud
You raise that rocker arm up on just one side (longer push rod), that will affect the ratio (slightly less) than the advertised 1.72

 

Maybe they need longer studs to work with your heads

 

.where did you end up getting push rods from ?