Originally Posted By: CNC-Dude #5585
Originally Posted By: stock49
Originally Posted By: OHC Sprint
None exist and haven't for a very long time.


Help us here Marc. We're push rod guys so re-grinding an old stick to a smaller base circle but higher lobe lifts can be 'fixed' with longer push rods.

Are you saying that current blanks can't be cut to the 'H' spec because there is not enough material in the rough cast lobe?

I get it that with an OHC setup the cam is running directly on the valve stem - so a blank cam shafts gross lobe diameter is the limit of lift that can be be ground in.


Yeah, the problem with regrinding an OHC cam is that you reduce the base circle too much and then you either have to use lash caps to compensate or use longer tip valves because the followers are not adjustable and cannot make up the slack created by the smaller base circle. You have to do each valve individually to regain what was lost by regrinding. Very tedious and a lot of skill required to do it correctly.


Add in the rarity of the motors, parts, skilled labor and the COST and just a handful of guys have ever done it.