i think that a 235 can be built to run past 4,000 rpm, but to try that with an old, tired 235 off the street is to ask for expensive sights and sounds.
Properly prepared--with attention to the crank, mains, and rods, the cam and valve train, the cylinder head, and especially the vibration damper--a 235 should do anything you ask it to do, within reason. Yet it is a small-bore, long-stroke, "antique" motor; it will not turn high rpm repeatedly and live long. It will not produce much "horsepower." Its forte is low- and mid-range torque that may surprise those who sneer at "just a six," produced smoothly, with a lovely, unmistakable sound.
With a 235, built to do what it does well, your '60 Biscayne is not a just another "street rod," popped out of the same fibreglass mold as the others. It is a true "hot rod," built to exceed what it was designed to do. Against its true competition, it can do right well--and collect more speeding tickets than anyone wants.
God's Peace to you.
d
