hey guys i really need your help here. I just inspected my stock air box and noticed that viscious filter paper inside is a little dirty, which means its time to change it. I want to replace it with a KNN FILTER for the time being until i get the after market air intake system. Has anyone done it??? if so please shoe me how its done. Do you just place the filter in the box and close the lid? You see I dont want to get rid of the box yet because, i have already two mods done, a midpipe and downpipe. So with the stock ecu i cant go into any other mods until i do my fuel managment system.

 

I think you mean K+N Filter. They do offer a stock replacement that just drops in for ~$60. Check out some of the vendors for it.

 

you are better off replacing the whole air intake system...stock is crap

 

Go look at the Pics I posted in the gallery of my modified airbox - the mod works well with the K&N Drop-In filter

 

i put a K&N in mine. basically, you just put the filter in the box and close it. It's a little bit more of a pain in the *** than that, but that basically all you need to do.

you should not have put a midpipe and downpipe on without a boost controller. Do you have a boost gauge? you'd probably see yourself creeping quite a bit if you did.

 

Yeah I have a boost gauge and i always make sure that i'am always putting out 11psi no more than that

 

Ouch... midpipe and downpipe... not a good 1-2 combo for first mods.
Better get an ECU or boost controller ASAP like Martini said. Or put back on the stock cat and get a cat-back or intake. In the world of stair-stepping your mods, you just took them 2-at-a-time.

 

If you want a K&N drop in replacement, I'm selling one here: http://cgi.ebay.com/ebaymotors/aw-cg...tem=1808293843

 

I wonder if he means the round type of filters in the stock box.

 

The K&N 33-2017 air filter is a direct replacement for the stock air filter.

$50 from www.summitracing.com

 

Please don't shoot the messenger here, but I thought this might be of interest to anyone currently running a K&N drop-in, or considering running one.

Coming from Cam @ Pettit Racing

Do not use the K&N drop-in replacement. It has been found that under heavy load, the filter sags in the middle allowing COMPLETELY unfiltered air to pass by and enter the turbos.

That would be bad for obvious reasons. Whether you want to trust that info or not is entirely up to you. Just thought I would pass it on.

 

I think he means just the k/n drop in filter.. i doubt he would wanna put more stress on the stock ecu with the mp/dp combo he's got already...

 

Damn. I ran that setup for over a year with no problems, but I might've been just lucky. I know Cam knows his ****...has anyone else heard of this happening? Definitely not good for turbo longevity...

 

maxpesce-

Do you have any instructions on this airbox mod? Did you seal up the area by the intercooler where the air box draws air from? I was reading Rob's site, and he shows that you should seal that area up....

~~~~~~~~~~~~~
Do not use the K&N drop-in replacement. It has been found that under heavy load, the filter sags in the middle allowing COMPLETELY unfiltered air to pass by and enter the turbos.
~~~~~~~~~~~~~~~~

My question on this would be under what load? Is he talking on a 600 hp+ car? Because I HIGHLY doubt on a stock car that it could suck enough to make the filter sag, and break the seal around the airbox. I am not even sure how this could physically happen. Even if it sags in the middle, the edges are being compressed by the edges of the airbox.


Later,
Patrick

 

pweizman,
you're correct, it is highly unlikely that a basically stock car would be able to cause that to happen(and I agree, that it is physically impossible), but maybe he was referring to "higly" modified car. Even then I doubt it could happen considering the way it "sits" in the stock airbox. If it were true, then the stock paper filter(which causes ALOT more restriction) should be sucked up and spit out as soon as you start the car. Not doubting Cam's knowledge, but just doubting the content or context of the statement!

 

Look closely at the photo: AirBoxMod-2 (https://www.rx7club.com/photo/index.php?photo=2042)
The baffle I made is sealed to the side of the radiator and attached to the rad. hose (& support bracket) it seals against the bottom of the airbox when the box is installed. The photo AirBox Mod-3 shows the baffle that closes off the back of the "Gap" and forms the air duct to the botom of the air box (between the frame and the baffle in photo -2). The photos show my prototype baffles that are made from cardboard covered with aluminium duct sealing tape. Also not shown in the photos is the fact that I still use the stock duct from the IC ducting to the Airbox. I plan on modifing the airbox further and modifing the baffle to eliminate the stock duct all together. I am still working on a write up w/ templates for the baffle to post on my website.

 

That sounds good. I know that on Rob's site it says you should plug up the inlet from the IC to the airbox as it can reverse flow, and cause hot air to be sucked into the intake...(BAD).

http://www.rx7turboturbo.com/robrobinette/coldair.htm

Let us know when you have that how-to up.

Later,
Patrick

 

I have a stock airbox, and the k+n filter in it. If you don't want to go hacking up your stock box to modify, or if you just want a filter for cheaper let me know....
mike@ucsbalum.com

 

That is true w/o the Mod BUT I think the mod as it stands now will greatly reduce that possibility, and in the future I plan to eliminate that duct all together.

 

The context was standing in front of my then-STOCK car, while he pointed at my airbox with the K&N drop-in filter in it. As for the content, give him a call and ask him yourself. (561) 844-2258

 

Simple question:

If the airbox was on the car (and secured hopefully)...how did you see that the air filter was sagging?

Patrick

 

When did I say I "saw" the air filter sagging? Cam informed me that this was possible, he didn't demonstrate it for me. I yielded to his knowledge and took his word for it.

 

That is cool.

It just seemed like you actually SAW this happen.

I will keep using my K&N...because I doubt it is any more likely to happen than using a OEM type paper filter.

Later,
Patrick

 

Besides K+N, Mazdaspeed also offers a drop-in replacement for the stock airbox (listed on corksport.com). Not sure what type of filter material it employs but its the only other alternative I've heard of.

 

maybe the sag he is talking about is in the direct center of the rectangle. as it sucks it up, the fibers spread, like cloth being stretched, allowing un/partially filtrated air through. i've never seen one so i don't know if it has the wire mesh etc to keep its form. you can imagine, even on a stock car, the pressure the large turbo would be pulling at wot. i would hope that k+n would have designed for that though. they make good filters.