[NJ 1161]

Seen a few threads regarding induction kits/ air filters on the 335d, so thought I'd experiment.



Bought a smallish 100mm neck cone air filter and replaced original air box.

Easy to fit. First thoughts are low end torque feels lower but then more at top end, but may just be my imagination!

I'm re mapped to 340bhp. More induction noise, and have a dump valve noise, and whoosh when accelerating.

I like the noise ( I'm sure a lot of you won't), but unsure as feel missing a bit of low end.

So, shall it stay or shall it go? All thoughts and commentary welcome. I did read that the extra air can lead to under fuelling hence less low end power?? Thoughts??

Tried to get bit of a sound clip but a bit rubbish. Not nailing it, just tickling it !

http://i456.photobucket.com/albums/qq288/dubz911/feecc4bd.mp4


Edit- not sure how to link to photobucket but think it will work if you copy and paste the link above?!


Thoughts are, if it stays, build heat shield and pipe cold air from centre vent and an extra air pipe from fog light?

[Danny.B.]

heat shield should help with the heat soak thats sapping your loss of low down grunt

[NJ 1161]

Would changing the filter really make an immediate noticeable difference? Or am I just imagining it?

[Danny.B.]

Well on my 888 Astra it had some fancy pants carbon fibre induction kit, to be honest i sold the car because it was painfully slow, when i PXd it for the BMW i stripped all the parts off it to claw back some cash, i put the standard air box back on and the car was incredible!! Made me regret it for a while!

What im getting at is, it was like this because of heatsoak on the open filter. And diesel engines get very hot too!!

But it sounds like yours isnt as drastic but still noticeable?

Oh and Can only see one pic mate and vid doesnt work...

[NJ 1161]

Sounds similar scenario. May do heat shield and see if makes a positive difference. Can't seem to post vid. If people want to view think you can copy and paste the link?

[dxb335d]

I'd be surprised if you haven't actually lost some power. Heat soak will be massive.

Does it sound any better?

[NJ 1161]

Sounds better. More burble and turbo noise, similar to a dump valve.

[DavS1]

I always bang on about heat soak on open filters, especially under the bonnet of an E9X where it's actually pretty well sealed for noise/keeping heat in. But that aside, there will be no leaning of mixture due to more airflow, as it's airflow metered so that means all air passing through the AFM is metered and fuel is applied accordingly I would say though long-term, the AFM may suffer due to worse filtration and if the filter is oiled like most cones, that lay's a coating onto the AFM causing failure.

Standard airbox FTW, or if you really need/want a cone, get one that's enclosed and has a cold airfeed from the front of the car, not low where it could suck in water from a large puddle though

[NJ 1161]

So no leaning of mixture, so am I imaging less low end?

Presumably heat soak means higher temps of air going in filter. Would I notice this immediately?

Has anyone seen vid to hear noise? Does c&p link work?

[dxb335d]

I know in the past you have said you do not want to post up about your car in fear of negativity. Rise above that and get a thread up. You have put a lot of work into it and are clearly passionate about cars.

Do it!! (I'm interested)

[NotNormal]

NJ......thereason for the loss in low end torque will I suspect be to the masses of heat being drawn in by the filter from the two turbos sat inches away from it
You might find a heat shield will reduce this, but as mentioned above, open filter in an E9x engine bay won't be helping your quest for power or better drivability.

If you want more induction noise and turbo noise, take the standard air box, add a panel filter, cut the front facing section next to the headlamp unit (this is a high pressure point) you will in theory have the best of both worlds.
More induction, more noise from the turbo and more air flow.....if you increase in power then that's a bonus

Just my thoughts

Tom

[zltm089]

video works...but not sure on how your applying the throttle....u didn't floor it did u?....as the rev counter needle seems really slow....

i'm a fan of induction/ dump valve noise!...(very few on here...)

[zltm089]

only "issue" with those "breathing" mods is that if you don't get it right then you might lose powerrrrr....

[NJ 1161]

No, not flooring. Applying gently with a pause. Trying to capture noise, and keep phone steady, and change gear!

[Danny.B.]

doesnt sound bad for a diesel mate!

[p1tse]

Good effort

Have you thought about a drilled oem air box?

[Si-M240i]

Originally Posted by p1tse

Good effort

Have you thought about a drilled oem air box?

wasn't that called a "foggy" in the good old days

[dxb335d]

Originally Posted by dxb335d

I know in the past you have said you do not want to post up about your car in fear of negativity. Rise above that and get a thread up. You have put a lot of work into it and are clearly passionate about cars.

Do it!! (I'm interested)

Just ignore me then dude.

[Statler]

Just a thought but if you've a custom map on (assuming..) then surely it was done with the standard air filter and air box, so in effect you've changed the parameters and the map now needs re-done to allow for the increased airflow?

On the e36's I used to knock about in, the guys always used the CAI type induction kit which had the heatshield, air intake and filter, but I can see what you're trying to do, just feel it's not going to work in this trim.

[NJ 1161]

Originally Posted by dxb335d

Just ignore me then dude.

Ahh, sorry dxb!! Promise I wasn't ignoring you!! I'll see what I can rustle up. Not really even sure which section to put a build thread in!! Surely we need a readers rides section?

Yes it's remapped but I think it's mentioned earlier in thread that air flow is measured so increased air should not cause reduced power. That was my initial thought aswell though!

Does have a nice rumble/ whoosh for a dirty diesel !

Oh, and I did try drilling the bottom of my standard box and made no difference at all. May however try taking the extra bit out in addition as suggested earlier.

[dxb335d]

Post up in this forum mate. This is for E9X. If it was another Marque then in Off topic.

[DavS1]

My bet's are (if you are feeling a lack in power) that it's definately heat related...1degree celcius is equel to 1bhp!

BMW probably spent a few thousand designing that airbox so it worked, it would have had a cold air feed as standard, I doubt there will be any way it can be improved upon UNLESS it was designed to restrict power, so that it didn't make as much as the model above perhaps? but I doubt it if im honest.
easiest way to test is refit standard box and see what you think!