The intake vlve can't hit anything as It's
closed at TDC for the piston(s)
Only true if overlap is less than zero (which happens: the intake valve opens ATDC, but not true in the stovebolt even with the 216 cam).
There's enough room to clear a stock or small cam because of deck clearance and gasket thickness. The high-lift 261/Corvette cam only clears because the overlap is so short - the valve has hardly moved by TDC. Cams with less lift but more overlap may have problems.
