You can hog those magnum heads out some for sure. This is the best pic I could find at the moment. There is a large restriction in the bowl below the valve seat. You can see this comparison on the 2 Magnum intake valves pictured. On a well ported Magnum intake throat, a golf ball will snugly fit all the way in the port and sit on top the valve guide, where it will not even closely set that deep on a stock port. Don't mess with the short radius that much, but the other 3 walls of the port should pretty much go straight down from the valve seat, eliminating the bottle neck.
Scott B.
"I'm a self-made man... I started with nothing, and I still have most of it!"
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