Any mods for a stock airbox?

[MrSlacker]

I purchased my '91 318is with a K&N cone filter installed instead of the airbox. I do like the sound it makes, but it is sucking up hot air from the engine which is bad. Anyways, I got a stock airbox and will install it. I heard from a friend that you can mod airboxes to still function well and produce a mean sound. Are there any specific M42 mods out there?

[Jorgeconrico]

I think leaving it stock is the best thing you can do.

[tjts1]

I purchased my '91 318is with a K&N cone filter installed instead of the airbox. I do like the sound it makes, but it is sucking up hot air from the engine which is bad. Anyways, I got a stock airbox and will install it. I heard from a friend that you can mod airboxes to still function well and produce a mean sound. Are there any specific M42 mods out there?

http://www.m42club.com/forums/showpost.php?p=48698&postcount=9

I think leaving it stock is the best thing you can do.

I think you can improve on the stock intake muffler.

[DesktopDave]

I never noted the missing high beam.  How well did you like the Autopal lights?

[Jorgeconrico]

That would work, but I would want to keep my car as close to stock as possible. It is a good idea though and I guess you would notice a performance gain?? I do remember reading this post awhile back. You are resourceful, i'll give you that. Who turns a strainer into an intake.....nice.

[Matt-B]

KN panel filter.


/thread

[tjts1]

I never noted the missing high beam.  How well did you like the Autopal lights?

Better than sealed beams, on par with cheap Halla ecodes but US elipsoids with clear lenses and 9005 bulbs are much better.

[PumpItUp]

don't forget this thread
http://www.m42club.com/forums/showthread.php?t=9223&page=2&highlight=cold+air+intake

the mini-mod with the grill is more reasonable for most of us on the street. at least more "sleeper". if you have time & money you can make an invisible ram system. can't find the thread but it was pretty nifty. if you just want bassy/farty noise you can drill holes in your stock box

KN panel filter.
/thread

are those any better than a paper filter?
is it worth spending $50 vs $10
i don't live in the sand dunes so I honestly have no idea, especially about the life of filters. i never had to change one, never had a single car long enough.
does it sound any different. for $40 might be smarter to deal with heat shielding the box or insulation on the headers or something

[MrSlacker]

Thanks for the advice! I am not looking to modify anything except the air box itself. Drilling holes is more of what I was looking for.

KN panel filter.
/thread

Matt, this actually brings me to the next question. Is it really worth buying the $40 K&N filter? Or can I just get a cheap one for 10 bucks?

[ww318is]

http://www.m42club.com/forums/showpost.php?p=48698&postcount=9

I think you can improve on the stock intake muffler.

Try the E28 535i intake tube PN 13 71 1 287 327, straight (not necked down)accordian type tube fits on the factory airbox and goes into the hole in the  headlight panel.  Looks factory.

[Choking Hazard]

Now there is the answer.   Thanks!  I'll try to find one of those too!

[dvmotorsports]

K&N is not as good as everyone thinks. The stock Mahle filter outflows everything on the market by over 30% except the WIX NASCAR filter which is well over $100 and they clearly don't make an application for our cars.

[thechadula]

For further clarification, the drilling holes approach (Swiss cheese) doesn't actually help correct the problem you are addressing (sucking in hot air) as everyone else has commented getting direct air from outside the engine bay is the proper answer.

[TooTall90]

http://www.motortraders.net.au/groups/group.asp?group=1&menu=1&article=3