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Old 02-25-2013, 06:01 PM   #9 (permalink)
bestclimb
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Quote:
Originally Posted by LibbyMetro View Post
i know it automatically adjusts the ratio, but would the cone filter make for less restriction, the easier it is to suck the air in, the less the engine has to work for it, I just want to know if the mpg gain is significant or slight.
No gain in MPG. Some folks come up with anecdotes otherwise. The plural of anecdote is not data.

If it takes 20% throttle opening to cruse at 50mph with the stock intake. Then we add fancy filter and now it takes 15% throttle to cruse at 50mph. All we have done is moved the location of that intake restriction. The same number of air molecules (and therefore fuel molecules) are going through the engine.

With a carbed engine intake restriction can reduce mileage but it is not so much the restriction as what it does to the fuel mixture. Fuel is forced into the airflow by a pressure differential at a venturi in the carb. By increasing the amount of vacuum before the venturi more fuel is forced through the jet per unit of air that goes through the venturi making the mixture richer. The choke on a carburetor does the same thing.
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