I built a B16 about 6 months ago with Skunk2 springs. The cams were left stock, but after a few months the power dropped off considerably. VTEC also barely pulled at all. After we disassembled the head recently I realized the cam lobes had been ground down to a flat edge where they were contacting the lifters. I've never seen this before. Could it have been the Skunk2 springs were too much for the stock cams? Is there anything I can do to prevent this?

adjust your clearances correctly and this will not happen

All clearances were set according to the Helms manual. I didn't check them when we disassembled the head. This happened to every lobe at the same rate of wear. I made sure I set all clearances before running. I don't reckon all could have come undone. Do aftermarket springs require different clearances? I still don't understand.

Is there any scoring on the rocker arms? High spring pressure could cause this but for the cams to be ground flat this pretty unbelievable. Is the head getting proper lubrication?

does your oil smell gassy??