Ace what do you mean by readjusting tappet clearance. Do you still adjust them for almost tight or do you give them a little looser adjustment. ERC
This is a very perceptive question!
There are two answers.
My comment to re-adjust tappet clearances was a simple answer that since there are changes to the rockers, the previous pushrod length would probably not be right, and would need to be adjusted to fit the new rockers.
However, the rocker ratio does affect the behavior of the valves, and the lash ramp of the cam must be considered. In order to maintain the same lash ramp timing for take-up of the valve lash, and to avoid changes to the timing at the .012" points, the general rule-of-thumb is to increase the lash adjustment by about .001" per tenth of rocker ratio. So, in this case with 1.15:1 ratio, it would be appropriate to add about a thou to a thou-and-a-half of cold lash when using these rockers. If not, the valves will begin to open while the cam is still on the lash ramp.
But, this is such a small ratio increase that if a person used the same "zero lash cold" adjustment as before, he'd simply add a degree or so to the duration, and probably not even have any notable effect at all on the lash ramp effectiveness.
When we go to higher rocker ratios, we do recommend that the lash be increased, and we also let the owners know that they can do some "fine-tuning" by using less or more lash in their final adjustment.
In the case of these Shotgun Rockers, it really isn't critical, but as long as you asked, I gave you the technical answer.