Basically what I was trying to say is that just like when I built my 493 I was shooting for zero deck and quench with about 10.5 comp for pump gas. I did not shoot for a setup to use the D-dished pistons as I wanted a flattop piston with quench and the comp ratio I was shooting for. But at the last minute I decided to use the 75cc EZ heads instead of the 84cc Eddy heads and the only way to now get comp in the 10.5 area with quench was to use the D-dish piston to have the comp I wanted and still have quench and nothing in the way of the flame travel. So to me I shoot for everything to work with the flat piston and only consider the D-dish piston if I have to much comp and a D-dish piston will get me what I want. I am not aware of any advantage of using the D-dish over the flat top other then letting the builder hit his comp mark and still have a good flame travel. Ron