Any body useing a stroked gen 3 hemi engine in there race car?

I like your build details so far. Hold onto your pistons, your only looking at going .015 out of the hole, which is okay if you have adequate material above the top ring and the ring is below deck. There are plenty of thick (although expensive!) head gaskets to maintain piston to head clearance. That gives you the option of switching to methanol, which works well with a Gen III. I’m guessing you’re running an MSD Hemi 6 and utilizing the knock sensors, so 15:1 with methanol can be fairly manageable.