I am working on a 68ss 396 chevelle. I am having a big problem with getting the valves to quieten down. The cam is unknown except we know it is a hyd.
I have tryed it running,not running.I have even had dirt racers to try to adjust them. I have even changed the lifters. I was just wondering if it be that the cam is bad or the lifter valley bores is wore? Any help on this would be very helpfull. I have been trying to figure this out for 2-years off and on.
Bud

This might sound odd, but have you checked for a header exhaust leak at the heads?

Thanks, yes i have double checked every thing I know too check.

Dup,

Impossible to know for sure without checking the numbers on the end of the cam, but I'm betting the cam is a Comp XE grind.

If it is an XE you'll never get it to quiet down. Comp XE's (Extreme Energy) are loud by nature. The only sure fire way to quiet down an XE is to remove it.

Dan

So what you all are telling me is i will have live with it or pull it? To be honest i wasn't expecting that. I thought it might be worse.But the car runs to good to for the cam to be wore.Thanks for your help on this problem. I know some of the warning signs for a bad cam is there any other I may not know.
1) spits through carb.
2) missing.

Dub,

If it's a Comp XE cam, and assumming the lobes are ok, it's got nothing to do with worn (wore) lobes. The ramp design of the XE style cam sets the valves down on their seats hard. The noise you're hearing is not lifter noise, it's valve to seat noise.

Some people with these cams say they don't hear anything unusual, but many-many say they do. Again, assumming the cam lobes are not actually going bad, then the only sure fire way to quiet it down is to take it out.

Dan