no problem about the delay.i havnt run it since i flipped it.installed new receiver,have to swap servos.havnt had time(ball playoffs,work etc.),plus the weather hasnt been cooperating.this week is doable,so im aiming to run it sometime this week.im going to use some valve compound to lap the head and sleeve as you suggested.if it looks good,then i'll run it without a shim.i know it'll be performing better as we are in the middle of a nice stretch of weather with low humidity and cool temps(60-65 degrees) all week,so i better find time before its too late.thanks again for your tips as well.