[quote=gregsdart][quote=HardcoreB][quote=gregsdart]there is a weird hump on the dome with a bowl in it for the plug tip. And the motor wanted theee more degrees timing than the 440-1 heads, which were milled to 62 cc, and no real dome, just a raised area about . 080 high. So i think that if i want to increase compression, that weird dome has to go.
Thanks Greg, can we see a pic of the piston again? Makes you wonder if the plug placement is 'perfect' in the chamber. I wonder how the engine would react to gas vs Alchy? It'd be interesting to see a burn pattern AFTER YOU ENJOY IT IN THE CAR of course. Although 572-13 heads have been around for a long time, I'm sure there's things to learn about them. To that point, if a builder learned something and it cost him some money, it's within his right to keep it. These are all things to consider for posterity, the consensus seems to be run it and tune it. Although if Gibby did those pistons, I'd still bounce your results off him. Not everyone hits a grandslam on the dyno. And in most of those cases I've seen, if the user doesn't sort it out in the car it never shows what the dyno did. Did anyone ever explain why there's a X cast into these? I never noticed that before. [/quote
these pistons were done by Diamond. I would think you can't hurt them by lowering that dome a touch. As far as what it will ru, same chassis, same headers on the dyno, same fuel system dialed in.
