Originally Posted by A39Coronet
Originally Posted by polyspheric
no amount of scoop is going to creat tangible boost in that way

200 mph = 2 psi boost

I saw no remark w/r/t the longer a car is at high speed, the smaller the intake needs to be. Those big scoops are needed for 0-100, not after.


Like I said, no scoop is going to create tangible boost like a blower.

Per Warren Johnson:

“If you plug in the numbers, you’ll find an increase in inlet air pressure of .142 psi at 90 miles-per-hour. Standard atmospheric pressure is 14.7 psi, so this represents an increase of just under 1 percent. If the air/fuel ratio is adjusted to compensate for the increased pressure, there should be a corresponding 1-percent increase in horsepower. For a 1,200-horsepower Pro Stock engine, that’s a gain of 12 horsepower. Hood scoop pressurization increases dramatically at faster speeds: It’s 2 percent at approximately 130 miles-per-hour, and 3 percent at 158 miles-per-hour. At the magical 200 mile-per-hour mark, the theoretical pressure increase is .704 psi, or 4.8 percent. That equals 56 “free” horsepower.

“Unfortunately in racing, just as in life, there is no free lunch. The penalty you pay for this increase in inlet air pressure is the extra aerodynamic drag produced by the hood scoop. A hood scoop is inherently dirty in terms of its aerodynamics. You can minimize the penalty with proper radii and contours, but you can’t get rid of it. And because the scoop has to be large enough to enclose the carburetors and intake manifold, you don’t have much latitude to change its physical dimensions and frontal area.

“From all of my calculations, it’s a wash between the increased horsepower from the ram effect and the higher aerodynamic drag produced by the hood scoop. In other words, though we gain horsepower from the increased inlet pressure, we have to use all of that power just to push the hood scoop through the air.”


And sadly for WJ, his performance calculations didn’t equate to real life MPH gains. Still today, the MPH is not where it should be for a Pro Stock car factoring in the average gains across the last decade before the scoops were eliminated. Plus, the cars look stupid with that flat hood, and since they aren’t any faster, bring back the hood scoop AND carbs.


Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston