Out of curiosity, how did this thread end up under Automatic Transmissions?

Good point. I moved it to a more appropriate forum.

-Jay

I read a report about using K&N in heavy equipment in very dusty conditions. A significant increase in engine failures.

Stock works fine for me.

regards
gary

Yea, I agree and unless you are driving in the desert and dusty conditions there on dirt roads and such, they do seem to last a long time.

I put a K&N in my '97 Escort and prior to doing it I had never exceeded 43 mpg on the highway. I just looked back at my mileage log and 8 of the last 10 fills have exceeded 43 and the other 2 were 42+ MPG. I'm not going to contribute all of it to the K&N, but I'm confident that it helped my FE. I paid about $45. for it and at the time I bought the K&N, Fram paper filters were between $15.-$20 at Walmart. I don't know what the price is now it may have gone up or they may have came down, but I don't have to worry about it. The K&N will last me as long as the car even if the car lasts as long or longer than my '88 has. I wouldn't tell anybody that K&N will help their mileage, but I can honestly say I think it helped mine.

The way I see it, any airflow restriction caused by a non-K&N air filter doesn't impact your mileage. When hypermiling, you spend most of your time driving at minimum throttle with the throttle plate mostly closed. So the largest airflow restriction in your air intake system is the throttle plate, which far eclipses any flow restrictions introduced by an new OEM filter or a dirty air filter.

Now if you were drag racing and going after maximum horsepower output at full throttle with maximum airflows, then you would want minimum intake airflow restriction and a K&N might help.

And/or low RPM, which has the same effect even if the throttle is wide open.

Re: K&N Air Filters - Worth the Money?
 

Thread Zombie here:

Short answer: NO. Tried it on at least 6 different cars and maybe 1 mpg difference.

The right amount of oil is difficult to measure.

I will never buy another one again.

Re: K&N Air Filters - Worth the Money?
 

I agree, for the fuel economy they aren't worth it.

Now, if you are putting many miles on in a year, or drive in dusty conditions often, it might be worth it in terms of filter replacement cost. It comes down to how often you change the OEM filter, its cost, and whether you plan to keep the vehicle long enough for the K&N to hit break even and save money.

Recharging takes patience. I've found it takes overnight to a day for the filter to dry out after cleaning. Then you hit the pleats with a quick spray. Purposely under oil the filter. Let it sit for 20 minutes to an hour, and then 'touch up' the non red areas. Definatily old onto the old filter for the times you need to car while the K&N is being recharged.

Re: K&N Air Filters - Worth the Money?
 

1. That hassle is Amsoil no longer makes their foam filter.
2. I always cleaned squooshed the foam on paper towels until it was as dry as I could get it, re-oiled and re installed and drove. When we changed the heads there were hatch marks....at over 350,000 miles, so I guess what I did worked.
3. Can't speak for anything but Amsoil and Wix, who shares the filter technology, but the smaller the particle removed from the air flow the better to keep wear causing dirt out.