Yes this one is 622" the torque and where it all occurs certainly gives away the stroke, but this thing is very conservative on compression and camshaft. Also needs a much bigger carb.. But I have made more power at 525" with a B1MC, never scanned the sheet though. Again dynos are dynos but that car went 170 at 2975lbs. Did ET worth a poo as it was set up for stop racing. The Predator will likely make more power than this 600-13 piece at a lot less cubes. But it is a better head, similar internals on each, both built for bracket and stop racing.