A rocker arms does not know which manufacturer affiliation it is assigned--hell, even rocker arms from various manufacturers, all of which are intended for a specific engine (ie, all of them made for an SBC), have geometric design differences between them. And so we are simply attempting to best optimize the valve train geometry given the components with which we have to work. At least that's how I'm attempting to help.turbo camino wrote: ↑Tue Dec 31, 2019 5:30 pm Are we still discussing how to set proper geometry for SBC rockers on a SBF?
Now if the OP changes rocker arms, then the process starts over again. That being said, I think these rocker arms can be made to work adequately...they may not be not ideal by my personal standards but they can nonetheless be set up to provide more efficient transfer of cam information than most setups I often come across in the wild.
A rocker arm that is "too short from pivot to tip" does not in-and-of-itself have any say whatsoever on pushrod length--let alone rocker arm geometry as a whole--since that dimension alone is only a piece of the equation. Incidentally the nominal, dimensional difference from trunnion-to-roller tip between the SBF and SBC rocker is 0.060", where the Ford rocker [for the SBF 20-degree head] would be 0.060" long relative to the SBC rocker [for the SBC 24-degree head].turbo camino wrote: ↑Tue Dec 31, 2019 5:30 pmThere is no pushrod length that will compensate for a rocker that is too short from pivot to tip.