I have a 396/375hp motor, all stock(i think) anyway I have this tapping noise only at 1100rpm's. Not at idle and not anything past 1100 rpm's. Won't tap when I first start car, it only does this once the car is warm. Any ideas what this noise is? I have junky headers (warped flanges) could this be an exaust noise? lifter? rocker arm?

You just named all the places I'd start looking. Exhaust leaks can sound like lifter noise. Check the headers for an obvious crack (around welds, dents etc.). May be a lifter going bad also.

Mark

I know the headers are junk. a few holes in the collector area and lots of visual black marks on the heads where the flange is warped. I've been driving the car since Early May 2000 and the noise is the same no worse. Would a lifter only make a tap noise at 1100 rpms and no where else in the rpm range? I had a car once that had a bad lifter and it tapped all the time and got worse at a higher rpm.?????

I would tend to agree with you that a lifter would continue to make noise throughout the rpm range. I have a small leak in one of my headers down by the collector that makes a tapping noise also. It goes away when you rev it up.

Mark