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Old 08-01-2013, 01:28 PM   #6 (permalink)
Aero Deshi
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Join Date: Jan 2010
Location: Vero Beach, FL
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MagMetalCivic - '04 Honda Civic Sedan EX
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Keep in mind that modern autos create much less CO emissions than older carbureted cars did. CO2 is not the same as CO. An air concentration of 380 ppm is constant for CO2 because that's what us puny humans have done to the atmosphere over the last 150 years. A level of 350ppm CO would kill you dead if you lived in a house with that level, it would take 6 hrs or more. At 3,500 ppm, say goodnight Gracie in 30 minutes. CO2 would have to be at 30,000 ppm or higher to kill you by asphyxiation, not poisoning. 5,000 ppm CO2 is the legal limit for exposure, so that is survivable for fairly long exposure.

Catalytic converters remove 99% of the CO from the exhaust, so the level is manageable at 100-1,000ppm AT THE EXHAUST.... by the time this is diluted down, it is negligible.

Diesels create 5 to 10 times the amount of CO at 1,000-5,000 ppm CO so they're worse.

Anything not properly tuned or without the catalytic converter is a CO death pump.

As always though, better to be safe than sorry...or dead.

Relating to the OP: You need to manage the air coming off the sides of the vehicle as well as across the top, just taking care of one or the other invariably means creating large pressure differentials within close proximity to each other. These lead to drag which would at least offset any gains that would otherwise be achieved, and may create more drag than the original configuration. The Kamm was really intended for vehicles with a trunk and a notch back to manage air coming off the roof, something with a square back needs an entire extension of the form in order to be effective.
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