Do they really give you 15 more horse power?
And do they really last forever?

I'm thinking of getting one for my truck so any info would be appreciated.

~85

 

No, they do not give you 15 HP. A clean stock air filter flows a sufficient volume of air to easily support a stock or stock+bolt-on mod engine.

Yes, for all practical purposes they will last for the life of your car.

 

Depends on how much air your engine needs. The K&N will sometimes be less limiting to the engine, so for heavy airflow you might get more power. But there are several problems with K&N filters.

From reading on a similar webpage, not personal experience...

The K&Ns usually sit in the engine bay where all the hot air is. Hot air means less performance. So you may get more air flow but lose the power due to hot air. For best performance you will need a cold air box. The stock filter at least draws some cool air from outside thru the airbox. I think some K&Ns are drop in replacements so that would kill this argument, but then you are then limited to surface area just like the OEMs.

Many people have experienced degradation of the airflow sensors on their intakes. The fibers or oil in the K&N appear to deposit on the little wires in the sensors and over time will degrade the sensor. Again you will lose performance, but it will take a long time for you to notice.

Many dealers will complain and some will disallow warranty work for the reason above.

The K&N requires periodic maintenance. I believe you need to wash them and re-oil. This is a messy job. With proper cleaning and oiling, the K&Ns will last a very long time. I would rather drop in a nice clean no fuss filter every 30K or so. In my opinion, the oil filter is almost 1950s or lawn mower technology, ie similar concepts and techniques.

Like most things made for "hot rodding", they really are meant for "off road applications" ie a vehicle that does not need to be reliable day in and day out. The filters in our cars and trucks are a compromise solution designed to give the best combination of performance, longevity, low hassle factor, ease of use etc. They usually are not best in any one thing.

Unless you are willing to deal with the negatives of off road parts, you should stick with stock in most cases. for hot rodding, these might be just the ticket, for everyday use, it depends on you.

Just my opinions based on reading.

Jim Henderson

 

I'd buy Amsoil's Eaa filter before k&n. I've had both and the main advantage is that the amsoil filter is oil free. Doesn't last as long but once you figure in the cleaning kits it evens out.

 

They don't do squat.
I have a slightly used one for my '94 4.9 if interested.

 

They wont do anything on 4.9l's. The Stock air intake on a 4.9l isnt what makes it slow. I drove mine running nothing but the throttle body around the block, no air filter hoses or anything, alls it did was sound cool.

All the big h.p. gain claims seem to be on newer vehicles, like 2000+ modles. If I was going to buy some cold air kit or whatever, it wouldnt be no 300 dollar K&N "fipk", it would be more like a 150 dollar DJ motor sports or some off brand deal. And I'd only do that if I was looking for another mile per gallon.

 

Thanks for the info guys.

I wasn't going to buy a whole kit. Just the filter. It's only thirty bucks so I think I'll give it a try.

My uncle really brags them up. He has them in all his vehicles...

 

I wasn't looking for power in the 4.9, but thought maybe a couple more miles from a tankful. I guess the computer takes care of that.

 

Im considering buying something cheap like an air-raid system for the chevy to try to squeeze out some mileage actually. 3 bucks a gallon is makeing my account drop!

 

I have a KN drop in replacement filter in my 95 F150 5.0. It runs alot better with it than with a conventional paper one. It does not give 15 hp though. That might be true if you add an FIPK setup to a Lightning, Cobra, or Vette though. It probably only gave my truck 5 hp. I don't think the drop in repalcements are advertised to give 15 though. The fact that it helps mine quite a bit may be due to the fact that my truck has a mass air sensor and is not speed density as most of the older ford trucks are. I have had mine since 96. I clean it twice a year. It probably only needs to be cleaned once a year but oh well. My family has them in all 6 vehicles. I do agree that the cleaning is a little messy but its not a big deal. I have a cheap paper filter that I use if I need to drive some where while mine is drying. You need to make sure that it is 100% dry before reoiling it. Also, don't over oil it. Spray just enough that you cant see any white areas and leave it soak in for a little while then spray lightly where you see white areas and wipe off excess with a paper towel. I would not even consider running paper filters anymore.