need help

[nattyice08]

right now i am going to college, and i have to commute everyday. its 9 miles one way, and its on back roads. i was wondering if anyone has a 92-95 GA that has put a k&n or cone filter on it. what kind of fuel mileage change did you get? i get about 21 right now city, but i need more than that. will a new filter help me? thanks

[rixGAphx]

A dirty filter will reduce engine power and milage.

On old carb'd engines, running without an air filter would generally gain either hp or milage, depending on one's driving style.

K&N and other cleanable-foam filters have a larger face area, but there is still significant restriction to the airflow.
It's *slightly* less than a stock accordian-type filter, so the engine will breathe easier.
All else being equal, at 3/4 to full throttle the engine will produce perhaps 5% more power.

Most people use this power/torque for better acceleration, and never realize any mpg benefit.
Perhaps you have more restraint than the rest of us.
Your fuel consumption at highway speed, say 75 mph, will get better.

But remember, that's only at 3/4+ throttle!!

At the lower engine speeds that produce good milage, being 2200 to 3500 rpm (the engine's optimum rev-range for hp-produced vs. fuel consumed), airflow restriction in the intake has VERY little effect! :eek:
Reason: The vacuum 'suckage' that makes the air move is greatest at these lower rpm, and it's great enough to overcome the restrictions of a stock air fliter.
The cone filter won't have any measurable effect.

When the filter is clean.

The greatest advantage of a K&N is that it gets dirty more slowly (some number of dust grains spread over a larger area).
After say 3000 miles, the K&N is breathing just about as well as when brand-new, while the accordian can be completely clogged with road dust (assuming nasty Arizona back roads).
And to clean the K&N it's just a few minutes on a Saturday morning at no cost, while the stock accordian is ~$12.

Even if the conical doesn't save a dime on gas, over the long run it will recoup it's initial cost by not requiring disposable accordian filters.

Just my $0.02. :D
-Rick

[Matt95GT]

K&N filters (replacement rectangle or cone) are a good way to avoid power/mileage robbing dirt clogs, but will not add up to any significant increase in fuel economy, unless your current filter is really that saturated in dirt.

Be thankful your commute isn't longer. Also, 21 MPG isn't bad for city driving... about the best I got when I had a 3100 GA. The addition of the filter made no change for me.