....on 'stock cars' NASCAR allows the air from the cowl area only because it is a 'clean air' area. Meaning it is the best place too draw air into the carburetor that is non-turbulent. The air is not forced into the carburetor but rather pulled into it by the engine vacuum. One of Carroll Shelby's old tricks was to adjust the hood hinges to hike the back of the hood up about an inch on his Mustangs...Junior Johnson also used this trick to extract the heat from the engine on his early stock cars. The term 'cowl' induction never intended for the air to be rammed into the car, if it had it would have been turned around called a scoop! My engineering started when I was quite young hanging around my dad's garage and junk yard. I was experimenting long before I could drive on the street...I used to have a dirt track outback and build old cars and drive circles all day...every time I blew up the engine smoke always came out the back of the hood and so did the water...if you watch NASCAR notice how when the engines blow smoke and steam come out the back of the hoods, that's why they can't see! If you will notice driving on a foggy night you can see the fog roll right out of the rear hood seam. If you really gotta know and see for yourselves pour some oil on the exhaust manifold or use a smoke bomb and test it...but please use something other than these beautiful PT Cruisers to experiment with. Trust me on this one...it exhausts out...do the windshield washer jets of water get sucked down into the rear hood seam? Jeff V as for the friction, it will be of no concern..just picture it like this. If air builds up under the hood and can't escape it creates an 'air brake' but by allowing it to escape out the rear it makes the drag coefficient of the whole moving mass much less. The coefficient on a PT Cruiser is about .38 (not to good) that's why it takes horse power and gear to get much past 120 mph. This one little modification can lower that to about .36 and when we lower the Cruiser about 1 1/2" it drops to .34 and that is about where most cars of today are at from the factory. Take a paper cup and hold it out side the window while running down the road...notice that you can't hardly hold it when it's opening is facing forward..now punch a hole in the bottom with your finger and try it. It will just glide with no resistance. Now transfer that thought over to the hood vent issue and you got it...
Inferno red GT/R-package/rear wing/5-speed
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