I have run a 280 degree 480 lift cam in my 235s for years with out having to recess the valves. The duration gives the nice rumpty rump that you are probably looking for, power runs from about 1500 to 4500 or so. Max rpm on the rods is probably 4800 to 5100, higher and you run the risk of snapping one in half (done that twice racing the 235 at rpms over 5500) If you are using a Stock head and it is a street motor, you might consider doing a light light surfacing on the bottom to assure flatness, clay up the pistons, powder or oil the clay so the valve does not stick, bolt the head back on with a used head gasket, rotate twice, remove the head, section the clay with a razor blade and measure the thickness. .080 is probably a good number for the exhaust valve clearance if you want to be sure.
