"I built a number of intake manifolds to help produce ball-busting power at the bottom of the gear and each improved ET’s. The manifolds included the first cast aluminum tunnel ram (Engineering project in school) which use d a Wieand BBC plenum, “the hairy one” which I made of fiberglass (NHRA refused to let me run it), and then once I was moving and shrinking the intake ports, my aluminum manifolds which were the first with a V plenum and semi-side-exit runners. This was all done to increase intake velocity."
Not only shrinking ports but intake manifolds as well to increase ET.
He also said this:
We’ve worked many a program where we used a record holding engine as a base line. In every instance, when the "soft" counterpart was tested, we’d gain perhaps only 8-10% more usable power, but the recovery time and acceleration rates were in a league all their own. As one would expect, the specific fuel consumption was always lower, but in every case the specific airflow requirement for the engine dropped considerably as well. So, now we’re making more power with the same displacement at the same or hopefully lower rpm ranges, and the engine’s consuming both less air and fuel. This not only verifies the fact that we’re achieving greater combustion efficiency, but the airflow relative to power notions that most believe in are no longer applicable.