hey yall,
Im buyin a k&n air filter. A friend said i should gain bout 5 hp and a mile a gallon? is that about right?? thanks

 

You might, you might not. I would not expect anything as far as HP and MPG are concerned...it might help but it wont be anything noticeable. So dont be disappointed if nothing increases.

 

I did not notice any hp or mpg increase with a drop in K&N filter.

My advice is to put the $40 - $50 toward something else that will actually make a difference.

An electric fan will improve your mileage, and an Airaid FIPK with a K&N filter on the end will give you a noticeable high rpm power increase. Each costs about $200, but if you got enough for a K&N filter you are 1/4 of the way towards one or the other.

 

Don't expect much from the K&N. I never saw any improvment in power or mpg on my 03. I keep accurate fuel/mileage logs and never saw a thing. Nor did I ever see any improvements from the tonneau cover either...

K&N offers one advantage, you wont need to spend 25 bucks every so often to replace the paper filter. Just clean and re-oil. But there's problems that happen from that. Over oiling can and probably will coat your mass flow meter sensor and cause pinging and other problems.

Good luck

 

I have a K & N, got it the first week I had the truck. I doubt it makes much of a difference in fuel economy or HP, but my truck does run great and I get very good gas mileage. I keep all gas and mileage records but have nothing to compare to except other F-150s. As far as getting oil on the sensors, just don't over oil and there is no problem. I like not having to buy paper filters all the time, I just cleaned the K & N at 17,000, I now have 24,000. The saleman that sold me my truck had been running one for several years and recommended that I get dual exhaust and a K & N. I did and am happy with both choices.

 

Here is a quote from K&N's website. You won't get better gas mileage with a drop-in K&N filter.

(Link)
http://www.knfilters.com/faq.htm#1

"Also if you add a K&N filter and the primary source of air restriction in the OEM system is the air box, you won’t see much of a difference in power or MPG unless you add a K&N intake kit to reduce the restriction."

 

Yeah, but how many people actually STOP UP their air filter. It takes me months to stop one up, and my truck is in the dust all day every day. When I say stop up, I mean clogged up solid. There's no reason to replace one unless it is completely brown. Paper filters don't lose their filtering ability as they get coated with dirt, like the oiled kind do, so I don't see a reason to replace it until it gets plugged.

 

The K & N actually performs better as it collects the dirt up to a saturation point. You need to read the studies on how it performs. I disagree with your statement that paper does not diminish as it gets dirty. It has diminished air flow. The filter has to be able to take out the dirt but provide good air flow while doing it. I compared the two, made the purchase and am happy.

 

Not just K&N's, ALL filters filter better when they're plugged. That includes oil filters, air filters, hydraulic filters.... It's the way they work. (The exception being electrostatic filters) The difference is that a K&N will not restrict the air FLOW as much as it plugs up. Filtration efficiency goes up, but flow rate doesn't decrease as fast with an oiled filter as it does with a paper filter.

With regards to over-oiling causing a MAF problem, A) if you follow the instructions with the recharge kit, you won't over-oil it, B) if you let the filter stand overnight before reinstall it, the oil saturates the filter media and you reduce the chances of over-oiling affecting the MAF, and C) by personal experience with over 100k worth of driving on K&N's, I've yet to see a problem with the MAF sensor on any of the three vehicles.

-Joe

 

I wasn't trying to say that you picked the wrong air filter, I was just saying that people here are air filter crazy!! You don't have to replace it until it stops up. It may or may not diminish air flow, but it doesn't diminish it enough to make a difference until it gets REALLY clogged. Think about it. When you clean your K&N, does your gas mileage go up? No. Same thing with a new air filter. It doesn't help anything except it gives you a new filter that can trap more dirt. You ought to see what the air filters look like on the tractors we have. When we blow them out, there's a pile of dirt that falls around them! Now That's stopped up. And the tractor still runs fine. And it sucks a lot more air than your pickup truck.

 

I understand and agree. I just feel that the K & N was a good coice for me as I can go so long between cleaning it and do not have to replace it. I was apprehensive the first time I cleaned, was afraid I would over oil it. If you can use a can of spray paint and have some common sense, you will not over oil it. The recharge oil is in a spray can and has a red dye. You just lightly spray the filter as if you are painting it trying to not run the paint. Just as in a coat of paint, more is not better. Once over it and the whole thing is red, you let it sit awhile then you are good to go.

 

Indeed, that's where the savings is at. Performance is as good as or better than a paper element of the same age and contamination level, but you do not need to replace it every 6-10k miles as you would with a paper element. I'm Waaaay ahead of the game cost-wise. In fact, the way I look at it, with the money my K&Ns have saved me over the years in paper filters, the K&N has paid for my electric fans and my tuner.

-Joe