I welcome any and all opinions on this subject. Just reply with a yay or nay and give me your reason(s). K&N air filters are marketed as a way to gain horsepower, but what about gas mileage. In this day and age you have to get as many miles as you can without going broke. I am driving a '96 Explorer 4.0L Auto Tran. 150K miles. What about the Intake Systems? Same questions apply.

 

Go with the intake. Get an airaid intake. Fourwheelparts.com, and summit racing both have them. They are cheap for an intake (i got mine on sale for $140 with shipping). I have one on my sport trac (4.0 V6) and it was good enough to beat a v8 f-150 at the race track, and gave me 15mph faster than a stocker on the 1/4. As far as gas mileage, i havent been keeping tabs on it.

 

I wouldn't suggest the K&N unless you are willing to clean them out regularly. They will dust out your engine if you forget about them. I would rather change out the paper ones more frequently myself.

 

They are generally good for 50,000 miles before cleaning. Or at least the airaid is.

 

Maybe if you never drive off the pavement, but I wouldn't trust one on a dusty road or driveway very long. I just like to put the bug in peoples ears who are thinking of these big name brand air cleaners that you will pay through the nose in cleaning kits trying to maintain that single digit HP increase.

 

Cleaning a K&N filter is no big deal. Hell, I have one on my Jetski and never clean it. Of course there's not much dust in the middle of the lake anyway. On my Explorer, I just keep an eye on it. After a day of 4-wheeling, yeah I'd probably clean it. But it probably doesn't need it. K&N say they actually trap more dirt the dirtier they get - obviously because they are clogging up. But on a normal basis, I'd say I'd clean it about every 10K miles. I live in Phoenix, probably one of the dusty areas in the country. So every other oil change, and 10 minutes - no big deal. Oh yeah, the performance gains from a cold air intake are great. If you can get 15 MPH in the qtr for just chaning the intake - no brainer - do it!

 

Another bonus for my kit, was i got a free cleaning kit.

 

I bought a K&N air filter a month after buying my SUV.
I would say that I clean it about every 20,000 miles or so. I don't go off roading a whole lot.
The reason I got it was basically because I simply looked at my stock air filter. I have the 5.0L with the canister air cleaner. They had my whole engine trying to breath through a tube that had an opening the size of a quarter. Just by looking at that set up you would think something wasn't right.
I didn't notice any HP gains, but I know that at a higher RPM my engine can breath better. I also didn't have any noticeable MPG gains.
Yeah, and the cleaning kit came with my filter. They give you enough of the cleaning solution to last the life of the filter.
I'm happy with mine. I would tell someone to buy one. K&N, Airaid.. whatever. Just as long as you get rid of the filter case.

 

Yeah, they are all basically the same design. I once talked with someone who owned cleaners from all differents companies. He said they were all the same as far as filter construction. It all depends on how much you want to pay for a name.

 

I went with the K&N and the HP is slightly noticable, but the throttle response is much better. Also, may I add, the MPG increased a whole 1 compared to a new paper filter. Next project is to clean the throttle body, for all I know there could be someone in there among all the varnish.

 

Also, look up adding acetone to your fuel for mileage. About 2 oz. for every 10 gal. Do some research and see what you find, pretty interesting stuff.

 

I noticed no gains in performance at all in the std airbox KN application, but I can't say if the FIPK or other more drastic intakes do any better. If you over oil your filter after cleaning, it can coat the inside of the rest of the intake tubing. The most I can say is that you don't have to open the darn airbox very often and you can reuse the filter for years. I do believe you get better air flow throught a clean paper filter. If you do more searching on line, you can find research proving no real benefit of going with a KN filter (at least for the std airbox application). Personally, I wouldn't waste my time on it again. Shoot, if your ride has 150K, why blow a good thing by trying to hop it up. If it aint broke, don't fix it.

 

http://knfilters.com/search/hp_search.aspx Go to that site. Its KN filters. They have the explorer 4.0 dyno results for their diff products. The reg filter doesnt even show an increase, but the kits show 6-8hp gains.

 

I was talking about a cold air intake with a conical K&N filter. Never tried teh in-the-box replacement K&N. If it's legal, ie not California, go with the cold air. That's where the performance gains are.

Oh, Douchnafka - you gotta clean the MAF. If you have any considerable mileage at all and never cleaned it, this will make a good increase in perofrmance too. Instead of being starved for fuel, the engine will get what it wants and you will feel the power difference. Throttle body will help too but the key component is th MAF sensor.