Originally Posted by
onehundred80
The OEM pulley grooves are about .135 deep and the rib on the belt is about .08 deep with squarish corners at the root.
You could conceivably make a groove say .11 deep with .020 rads in the corners, the width of the groove, included angle and the radii at the top would have to be the same as the OEM pulley. You would gain .050 on the inside diameter of the groove or you could make the outside groove diameter .05 smaller. It would be weaker because of the smaller radii but ....
You do not want to lose the existing belt contact area or it is a step backward.
The SLK grooves are not that deep. I measure .090". Shop plans to make a tool to duplicate the stock groove shape and I left him a belt with the fact it needs to sit flat against the pulley after the machining is complete. the grooves measured at the largest diameter after cutting should not be less than 68mm if cut at .090", 2.25mm's.