It’s mainly about the combination, and I agree going for that teenciest .25 of a hp is usually a waste and hurts the driveability. But it doesn’t hurt to try sometimes. While I had the last motor I built on the dyno 350 tbi engine, with a comp roller cam, EQ iron heads with vortec style chambers and a tbi intake pattern. We were running the stock gm tbi intake manifold, tbi unit I modified and the stock ecm. We were pretty happy with the way it ran, but I had this “stupid” tornado or some such name tbi spacer that I had acquired on a junk engine somewhere along the way. So for grins we slipped it under the tbi and made one more pull. I’ll be damned if it didn’t pick up another 8hp and like 10ft-lbs across the entire rpm range. It put that tbi motor across the 300hp mark - not bad eh!