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DISCUSSION => Engine + Driveline => Topic started by: dwf08 on August 12, 2008, 06:30:36 PM

Title: cold air intake??
Post by: dwf08 on August 12, 2008, 06:30:36 PM
has any one put on a cold air intake? and did you gain anything or is it more for looks? thanks
Title: cold air intake??
Post by: EN318isPDX on August 12, 2008, 06:35:39 PM
Quote from: dwf08;54750
has any one put on a cold air intake? and did you gain anything or is it more for looks? thanks


Its all about sound.. you may gain a few hp but you will need it to be tuned for more air, downside to this is if you don't do it correctly than its just sucking hot air from inside the engine bay.

IMHO money is better off spent elsewhere.. i just got a reusable K&N and it flows better and i don't have to worry about it getting soaked.
Title: cold air intake??
Post by: vonkamp on August 12, 2008, 08:21:23 PM
Do a search. tjts1 did one & posted a "how to" on it.
Title: cold air intake??
Post by: bmwman91 on August 12, 2008, 08:33:27 PM
My advice is to leave it alone.  Honest, you will more than likely lose power with it.  Seriously.  Sucking hot air is one bad part.  The other is that it changes the induction flow dynamics, and the car is tuned to work best with the stock dynamics.  Drop a few $ on a nice new paper filter and don't worry about it, trust me!
Title: cold air intake??
Post by: AcSchnitzer318is on August 13, 2008, 12:09:58 AM
I agree on keeping the stock box.  

The one exception to this I guess would be if you are running an aftermarket AF management.  Am I correct in that assumption?  As long as you have a proper CAI with a heat shield, you should pick up some ponies with the aftermarket AF running it right?
Title: cold air intake??
Post by: tjts1 on August 13, 2008, 01:32:29 AM
I actually had to switch back to my stock intake setup in order to smog the car today. Driving it back, the car just bogged after about 4000rpm. I think my cold air intake only works well with larger injectors. Otherwise you're wasting your time.

On another note, make sure you bring your car to full operating temperature before getting a smog check. You can't always count on the tester to do it for you. Leaving the smog check station (passed with 22# injectors and no throttle heater) my temp gauge was still at 1/4. No wonder the guy was done in less than 10 minutes. NOx at 15mph was 813ppm vs max allowable of 815ppm. Barely passed with a cold engine.
Title: cold air intake??
Post by: bosox1134 on August 19, 2008, 04:00:46 PM
i put the poweflow intake in from bavarian auto and i notice a big difference in power above 3000 rpms and it also sounds alot better. im now looking into building a new intake box but there isn't much room
Title: cold air intake??
Post by: xwill112x on August 19, 2008, 10:19:42 PM
get a oem style K&N...best u can get...
Title: cold air intake??
Post by: tjts1 on August 20, 2008, 02:15:23 AM
Quote from: xwill112x;55215
get a oem style K&N...best u can get...

ORLY?
http://www.bolhuijo.com/airflowtest/
Title: cold air intake??
Post by: EN318isPDX on August 20, 2008, 11:46:25 AM
Quote from: tjts1;55225
ORLY?
http://www.bolhuijo.com/airflowtest/


Nice broke link!! Well at least its down right now, I agree that K&N is about the best thing u can get. Cone isn't any better it just has a more jet style noise.

IMHO
Title: cold air intake??
Post by: tjts1 on August 20, 2008, 11:51:00 AM
Google to the rescue
http://209.85.141.104/search?q=cache:R64GmMTCAh0J:www.bolhuijo.com/airflowtest/+e30+filter+test&hl=en&ct=clnk&cd=1&gl=us&client=firefox-a

Quote
Mahle paper filter, OEM part
This filter consists of 74 pleats, each 1.8" deep.  If you unfolded this filter, it would be 22.2 feet long!  The surface area is 1438 square inches, or pretty much exactly 10 square feet.  The pleats have small ribs molded into them to keep them a uniform distance apart.  In addition, no wire mesh is required to keep the filter in shape.  As a result, this filter is the #1 performer in this test, adding only .11" of restriction to the airbox assembly.

K&N oiled gauze
This filter is the oiled cotton gauze type that every performance enthusiast is familiar with.  K&N is successfully marketed, but isn't renowned for the highest filtration standards.  This filter is #2 in this test, adding .13" of restriction to the airbox assembly.  This is the filter I expected to come out on top, but no matter how many times I reran the test, I could not get this filter to top the Mahle.  K&N boasts on their website that their filter media flows 50% more air than an equivalent area of paper.  With 18 pleats each .7" deep, the area of this filter is 202 square inches.  That's less than one seventh of the Mahle filter area.  I'd say the cotton filter media flows a lot better than they claim.  I'd feel better about it if I couldn't see so much daylight through this filter though.
Keep in mind that that Mahle paper filter goes for $7 (Pelican) while the more restrictive K&N cost $47.75 plus another $13.25 for the "service kit". I'm kind of anal about maintenance so I change out my paper filter every year or 15,000 miles. I would have to chance out 9 paper filters and travel 135000 miles before seeing a return on the restrictive K&N.
K&N = money down the toilet. Case closed.
;)