I have not heard of anyone doing this but it seems like a great application for a turbo or supercharger. With the exhaust and intake on the same side of the head, a turbo installation would be very clean. Typically you would run a lower compression, say 7 or 8:1, depending on the boost. Mid-70's motors with low 8.0-8.5:1 compression could work well with 5-6 pounds of boost. The 1974+ model 250s with integral intake manifolds eliminate the sealing problems you would have when you pressurized the intake tract. I am guessing you would also have to O-ring the head or you would easily blow a head gasket. If you blow through the carb you would need to pressurize it, this is a special application that I am not too familiar with. Unless you can fabricate an intake adapter to pull through the carb. It is very interesting to consider, that's for sure!
Say, who built your motor, I am looking to rebuild a 250 six with a little more umph.
