I wasn't talking about your A series BMC engine Chris. My experience comes from running old "American" iron.
Sid.
Sid - my bad - I thought the pushrods on the Jimmy were on the side with the ports.
Learning while pontificating, I am . . .
Yeah - I'd agree. If there's room to grind it out and get similar or better flow, and the class rules allow it, I'd say fence it and go for it.
But I will still recommend Vizard's book on the A-series for anyone forced to deal with shared ports, regardless of which side of the pond the engine was built.