Hey guys I have a 68Fbird w/a 455 6x heads - performer intake, Deamon 750, Mallory HYFire, 2000 stall, TH400 trans, 3:08 gear.  I was using a COMP XE262H cam.  I had previously used the cam in a 400 block that I was running in the same '68.  The cam is a mild 218-224 and lift is only 462-470. I've got two lobes on it rounded about 1/4 to 1/2 down.  The lifters are somewhat "mushroomed".  

I talked to COMPS tech line today we checked the spring height and seat pressure (both are well within spec) i was explaining to the guy how I had this cam in a 400 before the 455 and how I had purchased new lifters when I put it in the 455.  He said that was the reason for the ground off lobes.  He said 99% of the time, you will have cam lobe failure if you use new lifters with a cam that has already been broken in.

Last night I drained the oil and put a large magnet in the catch basin. There was NO sign of any metal particles in the drained oil. It was very clean and on top of that, this 455 has always had good oil pressure.  50lbs on start up, 40lbs while driving and 15-20lbs @850 rpm idleing on any hot day.

What do you guys think? Bad lobes becuase I used new lifters for a second break ***

Also - Should I pull the engine and break it all down? I mean the metal has to go somewhere right?

Thank you for your response.  

depending on what type and viscosity of motor oil you used after installing the cam,there is a posibility of correctness in the statement from comp about new lifters/ old cam.the material from the lobes went somewhere in the engine and at best you can only trap a nominal amount in the regular filter.  i would get the engine out ,apart,vatted, and renewed.this is too much "fun toy" to gamble with!  

new cam and new lifters w/ new springs will allwasy do the trick ,,,fresh oil and filter  

Attention to the original poster (if he's gonna see this topic again) Don't listen to "hot rod mike." Tear down the motor, I don't know how many engines he's lost to ruined flat tappets but it never turns out pretty, if you don't tear it down now you will probably ruin every bearing surface in the engine.