Reply to "Edelbrock F351 Intake (no 2V or 4V designation)"

The F351 intake is a 4V intake.

The Edelbrock intake runners are about 1.5 inches in width and 2.2 inches in height. This is the size of the 4V intake port at the push rod bulge. The 4V intake port is approximately 4.3 sq. inches at its inlet; its dimensions are 1.75 inch width by 2.50 inch height. It was designed to match with intake manifolds having high volume runners. Yet by the push rod bulge, which is only 3/4 inch into the port, the dimensions are 1.48 inch width by 2.21 inch height. This is about 3.27 sq. inches; i.e. the port’s cross sectional area decreases by one full square inch. Thus the first 3/4 inches of the 4V intake port, the section between the intake manifold flange and the pushrod bulge, is a funnel shaped transition from intake manifolds with high volume runners to a smaller intake port having about 3.15 sq. inches average cross-section. The Edelbrock manifold ignores the funnel, and attempts to keep the runner to port transition at more of an even cross-section, rather than fanning open to mate with the entire intake port. This really has no detrimental effect on the operation of the induction system ... but at the engine speed the intake is designed for it doesn't seem to help either.

The heads are most likely 1971 quench heads. As I remember it, the dot was added early during the 1971 production run. Only the earliest 1971 heads were cast without the dot.