Drop In Air Filter
 

just dropped off my 8 for a recall and an oil change...thought i'd have them install my new k&n drop in air filter...as i have a tendency to break things!!! :)
they instructed me that it would be a bad idea? that the engine would run worse...not better? that the mapping on the engine ecu did not account for increased air flow? did i spend 50.00 for nothing? i have had k&n's in all my cars and bikes and they always seem to add a little something, even if it is just noise...lol
also, anyone know about snow tires? i just aquired a set (4) of pirelli 235/45 17 on anterra wheels that i believe will fit...size good or bad? has to be better than the original 18" summer?
thanks,
don

The ECU only knows the mass of the air is passing by the MAF, not which kind of filter it came through. Even if the K&N has a lower pressure drop than the stock filter, the MAF doesn't care. It measures air mass, not pressure.

As long as you're using the stock air box and a drop in filter, you shouldn't have the rough idle problems caused by turbulent air over the MAF that some of the early intake kits suffered from. The only other problems I've read about is people putting too much oil on the filter and having it adhere to the MAF.

i had the mazdaspeed drop in filter and it was great. throttle response got a little better.

the dealership probably didnt want to deal with it and open up ur intake box and lied to you haha sorry. it's pretty easy to do yourself. 30 minutes tops. go for it. all you need is a screwdriver

You don't need any tools. Just take off the engine cover, unclip the two latches on the front of the airbox, push back on the upper edge of the airbox to get the opening wider (you'll have to use some force here, just make sure you apply slow, even pressure and you'll be fine). Take out the horribly wide stock filter (it should be fairly dirty, I know mine was, lots of little leaves and pieces of debris between the folds), and slip the K&N filter in, oiled side towards the front of the car. Then all you have to do is reclip the latches, put your engine cover back on, and you're set.

I noticed a slight increase in low- and high-end throttle response due to the higher airflow and I notice a very faint intake sound around the 3-4k and 6-7k RPM ranges where the secondary and tertiary ports open up. It's not significantly lounder and I only hear it when I have the sunroof or windows open. There's not really a gain in performance, but the K&N will cause a lot fewer headaches when it's time to clean it and it will allow your car to breathe more cleanly and freely (which is always a good thing).

I have the Mazdaspeed drop in and it improved throttle response, car runs great...

Huh?

the cars computer only knows how much air is going into the engine, not the pressure or speed of the air. so that basicaly de-bunks what the dealer said, in that the car doesnt care what filter is there, or if there is even one at all, it just looks at how much air is going in and adjusts accordinly.

RATS! KyLiquid beat me to it. I had a glorious multi-page, RotaryGod-like epic response prepared. :)

Summary: dealer is full of BS.

I would not put a K&N drop in filter in my car - or any car for that matter. Other than "in theory" saving money by not having to buy any more paper filters I think they are cr*p. They may flow more at WOT but also will pass more dirt and dust. Kind of like a $0.25 air filter VS a 3m Filtrete for your central A/C at home :)

You can find lots of info on the web as to how little extra flow you get and how much more stuff gets through.

A properly designed cold air kit can make more ponies just by picking up cooler air. This depends on the OEM air intake location and the design on the kit.

My opinion aside, the dealer is full of it since the car computer would adapt to any extra (or less) air it may get through the filter.

Dennis

thank for all the guidance!!!
i love my car!!!

is RB and K&N drop in filter the same?

racing beat sells the k@n drop in filter if that is what you are asking.


beers

Don't the cold air and ram air kits include paper filters?

i think most use k&n style or foam filters.

Green Filter gave me the drop in for mine, but i havent felt like installing it since i got it 4 months ago. I just cant see enough of an improvement to justify spending the money on one other than the fact, youll never have to buy another air filter. But really, whos not going to buy an intake or keep their car long enough to change the filter enough times to make it worth it.

I've been running my 8 (10-03 build date) with a Green Filter "drop in" for about 3,000 miles now and have had no idle issues. My dealer knows the filter is in there as I had to inform them not to touch it (don't want them pitching my $60 filter and replacing it with a paper one).

Looking at the filters during replacement the Green filter was about half the thickness of the stock paper unit and you could see daylight through it. It certainly looks like it should flow better no idea if it actually does or not.

After installation the car seems to show no marked improvement in any area nor does it seem to hurt the performance. I never dynoed my car but I certainly wouldn't bother after installing a drop in filter.

The only difference I've noticed is a slight increase in the noise level produced at the airbox (a muffled high pitch whine is barely audible from the cabin with the window down).

hmmm.....thats funny cos I got the mazdaspeed drop-in and it looks exactly the same as the stock only thicker. throttle response feels slightly better. As for sound level, only at very high rpms do i hear a slight whistle.

It's pretty easy to fit in the drop-in yourself although you got to use quite a bit of force to get the box wide enough to replace the filter.

where can you get a mazdaspeed air filter?

^ MAZDASPEED (Mazda) dealer or the internet? I think at least one of the vendors on this site should carry it.

The thickness I was refering to is the overall outer dimension of the filter. The rubber area around the filter is at least 50% thinner the the OEM paper filter. The material that is the filter is thicker and more transparent (can see daylight through the filter element) than the OEM paper unit.

Like was mentioned they have a K&N style oiled or a foam filter on them. At least with a properly designed cold air kit you can get a noticeable improvement in performance. It all depends on where the stock system sucks air. You do still have the issues of the non-paper filters passing too much cr*p into the motor, but you do get more power :eek:

Over on the 'vette message list a woman with a cold air kit recently hydro-locked her motor (and ruined it). Heavy rain and hitting a puddle at speed and the intake (sucking from low down in the cold air) gulped water and blew the motor. Something else to think about....

Most folks will also find that the exhaust and cat converter is too restrictive to flow much more so putting a high flow intake on does little good - unless you put a test tube or high flow cat and a better exhaust on at the same time.

Someone mentioned a car filter you could see through - I would not want to put that on my car. There is no way that will clean much from the air though it will be high flow :confused:

Dennis

The filter I droped in (Green Filter) claims that it will stop particles as small as 5 microns so long as it is properly oiled. I think that should be adequate filtration.

Is the Mazdaspped filter cleanable or is it one time use only??