? Valvetrain Geometry ?

Doesn't seem to be a "standard" when it comes to after market rockers. They all seem to be different lengths. The picture I posted above was my Comp Pro Magnum Rockers on my Edelbrock heads.
Agreed. There is no cookbook that I know of that will tell you which rockers will fit which heads. Valve stem height and mounting perch height and placement will affect the rockers tip placement.

I am setting up for the Crane Retrofit Roller install on my 360 and was going to use ported Iron J heads with a new set of Harland Sharps roller rockers. I had the heads set up with 2.05 valves and with the 1.6xx installed height for the Crans springs along with lash caps, the HS geometry was flawless!! Then I switched to a set of edelbrock heads and diff valves/springs and the HS run off the valves. I would need to modify the shaft mounts to get a reasonable placement on the valve tip.

So I have this new set of nice rockers (only installed for mock-up/measurment on new dry heads) that I can't use. Guess they will go up on classifieds in a few days.

I really like the look of the Comp Magnum rollers but would have to use dbbl ball end pushrods adding to my expense.

Not intending to hijack, but has anyone used the Hughes aluminum rollers rockers on a mostly stock closed chamber Edelbrock head? The pics on their site sure look good but for street/strip application, maybe the steel magnums would be the better ticket? Opinions welcome.