Can an air filter make differences in performance?

I used to have one of those $25 air filter from Custom Image shop but today, I replaced that with a K&N filter and I was surprised at the result. It felt like my car is running a lot smoother and faster. Of course, the K&N filter was bigger than my old filter. Anyway, I am really happy with the result.

Oh yeah, I just purchased a Supra Cusco front strut bar from optauto.com, I will test and see if this will fit on my SC400. The cost was about $180 with shipping, which is a lot better than the guys from lexussc400.com plus I couldn't wait until lexussc400.com restocks on the cusco strut bars.

Peter~

 

The K&N filters are much more superior than the cheap ricer conical filters thats why it is twice the price. Expect a ~3-8 hp improvement.


Remembre K&N 's need to be cleaned and oiled on a regular basis. Unlike the others.



Keith

 

I think is only 3 horsepower !

 

The K&N filter is a great investment in cheap performance gains. It has improved my gas mileage and the car is a little bit more peppier, It will make you leave a 12ft. black streak mark on the pavement I white smoked those son of a gun tires with that filter

 

improved your gas mileage. NOT!

I would basically disagree that a K&N filter offers ANY advantage over the factory recommended filter over the long term.

But, let's assume for the moment that it does.

Your engine ECU controls the gas/air mixture ratio pretty much to the nth degree. So even if you get more airflow volume per engine revolution into the engine the mixture ratio doesn't change.

The only NET gain I can see is a slight increase in HP. Does anybody out there truly believe an increase in HP will result in better gas mileage, unless the original engine HP was inadequate for the size and weight of the vehicle to begin with?

If you're going to go ahead and run a K&N filter then you should use the ROUGH service schedule for maintenance. Otherwise you might arrive at 40 to 50K miles with significant piston ring blow-by due to the additional level of dirt and debris contamination of your engine oil from your use of a less efficient, K&N, air filter.

Ansent an air cooling or compressing device, there are only two ways to provide more "freely" flowing air into the engine. A HUGE filter that has the same level of pore size, particle filtering efficiency, as the factory recommendation. Or a K&N filter that has larger "pores" therefore will still fit under the hood.

Obviously the K&N will not be as efficient at particle filtering as would the factory one.

Good Luck.

Oh, even if you re-oil the K&N on a more regular basis than they recommend and change your oil and filter on the rough service schedule, if in the end you do need to take the car in for engine service during the warranty period I would advise you to reinstall the factory filter first.

 

Cupete,
you can buy one from www.autozone.com and have them ship it right to ya. It is around $62.00.

 

$49 at the chicago place, same filter

 

The only Dyno results I have are for RX-7's, mustangs, and Vettes; but a stock 85 GSL-SE with factory fuel injection gained 3 hp with the K&N factory replacement filter. The same car, with an open exhaust, gained 8 hp with the K&N conical filter over what the exhaust alone improved. (i.e. I dynoed the car w/ the factory k&N replacement and open exhaust, then installed the conical filter and dynoed again, and it was a 8 hp improvement; but that was on a rotary.)

a 93 Mustang GT - K&N cone filter-no heat shield yielded 6 hp
a 2000 C-5 Vette yielded 12 hp from the twin snorkle kit from K&N

Like erfan, I have noticed a very slight improvement in fuel economy- VERY SLIGHT. My only explanation is the engine breaths better, and is mostly in part to not having the intake restricted. Sort of the reverse of why a cloged filter will lower gas meilage. I believe the K&N allows the car to reach its optimal economy, as opposed to giving it better economy.

I only like the K&N because it uses more surface area , rather than much larger pores to allow more air flow. The pores are slightly larger, so they use filter oil to electrostatically accumulate the dirt that would normally flow thru the pore opening. Thus a slightly dirty filter will filter dirt even more than a perfectly clean filter - weir science, but it works. K&N is the only company to my knowledge that does this. But you have to be care when applying the oil, don't over apply it.

I purcased an RX-7 in 1988- brand new. The car was ordered, so I had to wait 3 months to get it. In the mean time, I supported the US economy and bought all the goodies for it; including a K&N filter. I received the car w/ 3 miles on it. I put over 120,000 miles on it before I tore the engine down for performance purposes only (got the urge to juice it!!!!). The car was running very strong when I tore it apart, and there was no abnormal wear of the housings or seals (equilivant to a piston ring and cylinder walls). In fact the tolerances were on the upper end of the acceptable levels. So, from my experience, a K&N is a Proven safe upgrade for any of my cars. But to each his own.


Keith

 

A guy with a stock intake had a K&N cone on the end of his intake on his GS300. On the dyno at DynoSpot Racing in Mountain View, CA they measured a 6 whp gain going from the K&N cone to a foam Weapon-R V2 filter. Similar gains can be seen with HKS's foam filter. They're the highest flow of all possible filter types.

 

I would like to get a cone type air filter, but would I have to buy the MAF adapter? Or is that just for the Apexi, which I would prefer over the long run. Also, with factory air filters running $20+, the $60 KN pays for itself.

 

Pretty much any cone filter would require the adaptor - 24-29$ - shop around; K&N cone filters are running ~40$ ($43 from Autozone).

Keith

 

Thanks for the tip, I will see about a conical one