Much to my surprise:
Not all screw in rocker arm studs are created equal!
The machine shop supplied me with PBM 7/16" screw in rocker arm studs.
Laying a straight edge across the installed studs revealed an unsettling picture.
The studs were so far out of concentric that there were gaps of about .025" at adjacent studs!
I have not been able to find a concentricity spec for these studs, but I measure .012" or worse!
I have installed ARP studs, guaranteed to be concentric within .005".
Laying the straight edge across them now gives a whole different picture.
Worst gap across the entire 8 studs is barely .003"
Most are touching the straight edge..........
I am smiling !!
Not all screw in rocker arm studs are created equal!
The machine shop supplied me with PBM 7/16" screw in rocker arm studs.
Laying a straight edge across the installed studs revealed an unsettling picture.
The studs were so far out of concentric that there were gaps of about .025" at adjacent studs!
I have not been able to find a concentricity spec for these studs, but I measure .012" or worse!
I have installed ARP studs, guaranteed to be concentric within .005".
Laying the straight edge across them now gives a whole different picture.
Worst gap across the entire 8 studs is barely .003"
Most are touching the straight edge..........
I am smiling !!