Its called ring flutter and that's exactly why most ring makers now use a bigger end gap on the 2nd ring
I highly doubt that's what's going on here but I have been wrong before. my bet is the valve seals and possibly even a worn valve guide.
I recently had a 69 Camaro convertible in the shop that was puffing out blue smoke over 4000 rpm, it was the valve seals.
easy way to check if that cylinder is firing right is with a water bottle on the manifold no hiss means cold/dead cylinder
Last edited by bigblocks; 08-04-2013 at 09:47 PM.