It doesn't seem to be damaging anything that I can tell. I am having intermittent lifter noise. I am thinking air may be getting introduced into the lifters. It had a comp cams hydraulic flat tappet and I got tired of the lifter noise and changed it to a sig erson roller with scorpion hydraulic lifters. I am still having the same intermittent lifter noise. On a cold start up the lifters may or may not rattle (it usually seems to be one lifter at a time). After warm up the noise will go away. Last week I ran it at the track with the exhaust open and didn't notice any problem. Engine ran great and never missed a beat. Capped the headers and started the engine for the drive home and could hear a very loud lifter. After a short distance the noise quit and it is running ok now. Sure would like to stop the noise though.

Roger