Quote:
Fast rate of lift camshafts and too much spring pressure will overide the hydraulic mechanism.
Some of the cheaper lifters can't handle it. 
Keith
Bingo!
Thats why i highly recammend the Anti-pumpup lifters like the Pro-magnums, I have had nothing but problems with the standard lifters & fast-rate lift cams, I think thats were comp & others make that mistake by putting there "basic" style lifters in the cam kits, thats why its best to buy them seperately, may cost a bit more, but hey, in the long run your happy, no excessive noise.
I've run a few .284H cams in both SBs & BBs, at 1st. i learned the hard way, then took the advice of a mopar member about 10yrs. ago. Buy the "Pro-Magnum" Anti-pumpup lifters & set the preload at 1/8" turn.
| 
