[Toyaholic]

Originally Posted by mxracer_72

Dan,

Please let someone else drive your car on the interstate at ~70mph. Then, you roll down your window, open your mouth, and breathe. Try to tell me there's no such thing.

As far as I can tell, the idea would definitely work... the concept seems similar to the intakes I've seen on some Vettes (and on my streetbike). In another example, the factory-rated horsepower on my 2006 Yamaha R6 is 125hp without the ram air effect, but 131hp with. Doesn't look like much, I know, but its actually a 4.5% increase.

Any positive pressure will help the car make power (I can dig up my old MathCAD files and textbook examples from Aerothermodynamics, if I must). However, this rules out letting the mail slot supplement the factory air box. The pressurized air will go for the easiest route, whether that be into the intake or out the other side of the airbox. For the ram air to work, the airbox needs to be sealed.

Someone else mentioned the radiator heating up the air that would go over it. Although I'm sure the air may ever-so-slightly heat up, my intuition tells me the ram air effect would outweigh the slight loss from heating. Also keep in mind that the mail slot would pull in air MUCH cooler than underneath the hood.

If someone designed an intake that used the mail slot, assuming the slot size was adequate, it would most definitely add horsepower. The effects of cool air, positive pressure, and a straight-to-the-intake design would all culminate in power gains not seen by current stock or aftermarket intakes.

Now that's a breath of fresh air.... pun intended!

It may not be true forced induction via ram air, but cool air and the little bit of force (or less resistance) has worked for me. I can feel it on the "seat of the pants" meter!