In Reply to: Re: Aftermarket bonnet air scoop for E28? posted by Scottie on January 14, 2001 at 21:58:14:
I don't understand this thread of there not being enough air in the engine compartment to supply the engine. The entire bottom of the comartment is of course open to the atmostphere, the car is zooming through the air at high speed, and -- as if that wasn't enough -- the engine fan, and possibly the a/c fan -- are pulling air into the engine compartment at a high flow rate.
I can understand how some of you may think that you could loose some HP sucking hot air. But what is the temp difference between the engine compartment air and the outside air? Maybe 40-60 degrees? How much HP do you think this is going to make? 2-4?
Hot rodders have used K&N filters atop their carbs for years. Admittedly, some of these use scoops, but I've seen some pretty big engines under Chevys and such and they don't seem to be starving for air. I mentioned in another post that I once had a Jeep Wagoneer with a 300 cid V8, hooker headers, an Edlebrock 650 intake/carb setup and a 3" x 14" round K&N Filter atop the carb. It makes the cone filter on my BMW 3.5 look puny. That thing sucked more air and fuel during one smoky 4-wheel burnout than my BMW 3.5 could use going to and from the market and that Jeep never seemed to be starving for air.
Just some thoughts...
535i (w/ a K&N Cone in the space in front of the coil...)