Originally Posted by Skater30

You're obviously way more technically knowledgeable than I am on this subject David, but I can almost guarantee you're not going to see any true "ram-air" benefits in performance. First of all, the cowls are not sealed, which would be necessary to provide true "ram-air" induction to the throttle bore. They have vents/drains in other areas of the cowl that allow air to escape, negating true "ram-air" effect. And if you rigged a sealed tube from the air intake to the throttle bore for true "ram-air" intake, you'd be risking ingestion of water if you ever took spray into the intakes (which does happen). As an example, we run the injector hats backwards on the K-boats we race out here in California so as to not injest water spray from other boats. When we go to try and set a kilo record, we don't turn the hat around to face forwards, as they go just as fast with the hats facing backwards, even though there's 140+ mph ram-air right into the butterflies when facing forwards! And, I can tell you from 15 years of experience with 28s that these rigs take more than small gains of 3-5hp per engine to even be noticeable on the speedo head, or in the seat of your pants. I do really like your enthusiasm and detailed knowledge of performance equipment though! Let us all know how she runs..........

Originally Posted by Taboma

Ordered a manometer to test with this spring. I should be able to test from the plugged temp. sensor port in the intake manifold. It will be interesting. The issue of a sealed induction system is valid to a point, however, think of a compressor air nozzle pointed at the fill opening in a balloon. The compressed air will fill the balloon and expand it to a point until the pressure in the balloon exceeds the blast force from the air nozzle. It is pressurized, but not to the pressure of the compressor. The idea is to stack air in the plenum to counter the deficit created from the negative pressure (in relation to the atmosphere) the engine creates at WOT. The formulas posted show that it takes very little enhancement of pressure to achieve additional HP. We are talking of .75 to 1.25 PSI in the scenarios posted to achieve 22 to 28 HP respectively. I think that the cowl will act like the "balloon" analogy. ??? Maybe! Man am I tired of the cold weather. I need to be in my boat.