K&N Air filter + HAI? Come discuss.
 

I'm about to start the HAI on the '01 SL1 and I realized I wanted to do a nice tune up on the car since it's at 100k miles.

Thinking this through, I've noticed my HAI on my '96 made my air filter pretty dirty after just 1 year or 8k miles of use. It's now been 2 years and 16k miles of use, and it's time to replace it. At $10-$15 each, that's not a bad interval to live with.

But, I could get a K&N filter for $46 and be able to wash/reuse it. I plan to put at least 50-60k miles (maybe much more, who knows?) on the '01, which would translate into 4 air filters... or $48-$60 in air filters over the next 6 or 7 years.

I'm wondering though, with the addition of a HAI, do you think mileage would benefit even more with a proven product like K&N which will out flow a regular paper air filter?

MORE AIR + HOT AIR = even better gains?

Should I go w/ a K&N or a stock paper filter? Financially and logically, which makes the better decision to you?

Thanks

Would hot air loosen the oil on the K&N and make it foul your MAF (as well as removing the K&N's filtering ability)?

I would stick with a paper filter myself, then again I get over 50,000 miles on a filter in my vehicles because they all have oversized air filters in them.

I've always heard that K+Ns let in a lot of dirt. the particles that they let pass are a lot bigger than the paper ones. that is just what I have heard.

you still have to purchase the oil recharge kit to clean and re-oil the filter which also adds to the cost.

Yeah, but I believe their claims of increasing horsepower. I put one on my Z28 and it was a noticeable seat-of-the-pants difference. Never had any problems w/ debris/dirt clogging the throttle body or PCV or anything like that either.

I was just thinking more power would be nice with a HAI... at 160*F IAT there's a power loss. IDK how major of a loss on the SOHC, but in my DOHC it makes accelerating a challenge. I'd guess 0-60mph time takes twice as long at 160*F+ IAT.

I'm just wondering if feeding the car a little more air would help w/ power and maybe maximize the benefit of a HAI.

It kind of seems like it would have to. Seems like a no-brainer. I'm quibbling over the financial difference and/or benefit, as well as maintenance intervals really.

I think a Z28 might be a rare application where just a K&N could make a difference; as a car made to deliver the maximum in cheap speed, it may have real compromises in the intake, especially since they knew that most owners who are interested in going fast would upgrade the intake anyway.

The Saturn, not so much; it probably has an intake better matched to its engine, tune, and exhaust.

As for debris/dirt, the issue is what you'd like to go through your engine, not fear of clogging the throttle body or PCV...and my meta-sig has a link to some decent air filter efficacy testing that includes K&N and paper.

Nice info on the air filter testing. I gave it a looking-over yesterday.

Well, I'm torn really. The SL1 has a brand new filter in it anyway. My SL2 filter needs replaced. I guess if the SL1 fits the SL2, I'll swap them and only need to buy 1 filter. I'll probably flip a coin on the decision of K&N vs. stock paper.

i used to use k&n exclusively on all my drag cars. it was worth it just for its reusability. ive since descovered accel cool blue. its much cheaper and just as reusable. i think it may even filter better. cleanings yeild more crap. for my hai a reusable filter is a must. after a few thousand miles on my brand new filter it was looking bad. usually it takes like 50k to look that bad. cool blue off ebay is like 10 bucks. i have them in everyone of my vehicles. never an issue.

I've got a K&N in my '97 Escort wagon. Im not sure just how long it's been in, but my guess would be 10K miles and it hasn't needed a cleaning and recharge yet, as a matter of fact last time I looked it still looked new. I won't say for sure that it helped FE, but I'm pretty sure on this particular car it did. The car is 99+% used on the highway with very little city or short trip driving and I think the best mileage I ever got prior to the K&N was about 42-43 MPG/highway and since it has been installed I know I've got 44-45 MPG/highway with the A/C going and as high as 49.85/highway without it. I've got a recharge kit in the garage, I think I paid about $10. for it and think it will recharge the filter about twice.

you could create the same effect of the K and N by making your air intake more direct, I achieved my best results when I restricted my air intake opening maybe 15% with a piece of tape, not saying that it necessarily caused good results, but I did that to ward off water coming in from underneath... I believe restricting air intake size is worth looking into.