Cam re-grind

When they regrind a lobe, they reduce the base circle.

Depending on the original lobes and LSA, you can only change the lobe a small amount.

For example, if you have a cam with say, 280 advertised duration, .480 lift (.320 at the lobe) on a 112 LSA, it would be difficult to make it much more lift or close up the LSA more than about 4-5 degrees. Or gain more than .050-.060 lift.

Ken from Oregon cams can give you more precise numbers.