The Wayne chamber appears to be open, with no quench surface. I assume the piston shown is close to zero deck at TDC.
This means the engine will have lower compression than the stock 261.
The 261 head's large chamber volume is partially contained in the exhaust pocket. Without a custom piston there is no way to get a compression dome.
With pop-off valves tuned for 10 pounds of boost wouldn't a tight quench area lead to detonation on pump gas? Seems they built it with a lower static compression by design.
