Hyd Roller vs Hyd Flat tappet on SM heads
Real question - If the rockers are too short, why do all of the B3 kits I've seen photos of on this site move the rockers up and away from the valve?
Because the shaft mounts end up too low and too close to the valves as the valves get longer.
The shaft location was based on a little over .400 lift and whatever the stem height is supposed to be. I forget the stem height number.
When you change the length of the valve, lift or both you need to move the shaft.
Also, switching to a roller tipped rocker changes shaft location.
And certainly the length, ratio, adjuster location and overall length of the rocker changes where the shafts need to be.
If you picture in your minds eye a straight line running through the stem of the valve you’ll notice that that line gats closer to the engine centerline. That means the tip of the valve is now closer to the shaft.
The ONLY fix for that is to move the shaft away from the valve, moving the shaft closer to the engine centerline.
Then you need to raise the shaft to account for the longer stem height.
A much better and correct explanation of this is in the tech section at
b3racingengines.com.
I suggest everyone study Mike’s tech pages. If everyone would read his stuff there’d be far less screwed up, out of control, guide eating Chrysler valve trains out there.