I have run a few reground cams over the years. How radical the cam can be reground depends on the cam core itself. Stock lift is in the .404 range. Typical regrinds come in at the .410-.430 range, sometimes a little higher, depending on how worn out it is. That being said, came cores are like any other part, tolerances can be close or wide. Chet Herbert reground a couple of cams for me, most were in the .450 range. The last one he did was back in 1985. That core was an exceptionally good core and he was able to regrind that core to .480 lift 280 duration. I still have the 235 motor I installed it in. Choppy idle and fun to drive, sounded great with the clifford tube headers open. But I think that cam was an exception. At any rate, 264 degrees of duration .450 lift is a pretty good street cam with pretty good street manners. The stock 261 and corvette cams are not all that great in my opinion. About the same lift as stock .405 as opposed to .404, about the same duration, the ramp events are where the changes seem to be. A much better alternative would be Langdon's bull dog cam. That cam is like .435 and is a really good choice. A little warmed up but not so much so to make the motor run choppy. Nice rumble, nice idle. I dont think Tom Langdon sells them himself any longer but Tom Lowe over at 12bolt.com sells them now and has some in stock last time I looked.
https://www.12bolt.com/store/p545/235_261_BullDog_Hydraulic_Camshaft.htmlMy guess is that if you wanted something similar in a mechanical lifter, any of the good cam grinders could make something up that would get you in that range.
