Paul,
There is also the possibility that simple things didn't work; enough cam lube on the lobes[I like crane cams lube] prime engine and start immediatly, keep revs up 1,800 to 2,200 rpm for the first 20 minutes to break the cam/lifters in. On very aggressive cams you can break them in with lighter valve springs then change the valve springs after the engine is run in, this will save alot of wear.
Good Luck,
Perry.
