My Mega 540 came with domed pistons despite me telling the {now gone} jerk Indy salesman that I wanted 13.0-1 on my 440-1 540 kit. I will cut those pistons flat the first opportunity if I don't dish it to 10-1 instead. C-16 vs 110 at half the price and easier to get.

All the comments on flame propagation, quench effect being ruined, trapping unburned mixture, were pretty obvious to me when I looked at the domes and the chambers and thought about the quench flow with that damn hump in the way.

Let's talk about a guide for that quench flow toward the plug or ??? Cut into the flat of the head? Easy mill job or hand.