yes it is an odd size. That is where the cylinders honed up nice, straight and round.so I decided to change bore size and C.H. for close to 10 to1 comp.Diamond allowed us to change any two things on piston no extra charge.I am freshening up motor since rebuild 27 years ago.I have removed the forged speed pro low compression pistons,8 to 1 comp., in favor of the diamonds.On another note, Diamond responded by Email to myself and talked to my machinist on the phone today.They told me it is common on aluminum rods and extra wide OEM rods.That is why they ask for that info on customs and they would take a cut on the pin towers.But my argument is the rods are factory width 1.2",some are up to +.002",and some down to -.0005" My machinist is still working on them to see if they will help out.I guess maybe I was confused,I thought we started with a 340 piston and made changes from there.They said the job number on the build sheet was a mistake and that was a LS1 number. The number on the piston is right and the one traced to my machinist.So I guess these 700.00$ pistons are going to cost me a little bit more.Yes well, its only money, I'll make more tomorrow.