As some of you know, I'm building a Hi-Po 425. I had Ross make me a set of pistons that would make 11:1 compression. They have a huge dome because my chambers measured in at about 114 cc's after unshrouding the valves a bit.It seems that Ross made a nice piston except that they didn't leave enough room for a stock spark plug to screw all the way into the chamber.It's not the dome that's the problem. (The dome is on the other side of the chamber).When I cut off the electrodes, the plug fits O.K. , although I haven't made a clay mold to check vavle and plug clearence yet, but at least it screws all the way in at TDC. Ross has offered to take back the pistons and re-machine them, or they said I could machine them myself with a diegrinder. I really don't like the idea of doing this myself, as one wrong move and the piston becomes a paper weight. For them to do it I have to get the rods off and they have "Spiral Locks" holding them on and I've heard they are a nightmare to get off. I found them easy enough to get on though. I think another option would be a racing plug that doesn't have the protruding electrodes.So, anyone ever expierience a problem like this?Even if not, any good ideas out there? This is one that has me kinda stumped( and upset) :crying2: P.S. Anyone ever remove spiral locks and know a trick for that?