I know a guy wanting to build a 4.150 or 4.250 stroke 400 block engine. I've looked at Scat and 440 Source stroker kits. I would like smaller (more modern) rings like .043/.043/2mm or 1.2/1.2/2mm. Does anybody make an off-the-shelf piston for these motors like that? I know Diamond will make customs, but $$$. Thanks.