M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Engine + Driveline => Topic started by: bullmand on September 26, 2006, 06:06:51 AM

Title: E36 M42 airbox.
Post by: bullmand on September 26, 2006, 06:06:51 AM

Has anyone experimented with putting the airbox from an E36 M42(specifically in this case a 1995 318ti) on the E30 M42? I was thinking about it yesterday and checked some part numbers and some dimensions. The stock E30 M42 filter is 10x5.75. The E36 M42 filter is 9.25x9. That's quite a bit more surface area, but would it make much difference? From looking at the parts diagrams it doesn't look like it would take much effort to make the E36 box fit. What do you think?

Title: E36 M42 airbox.
Post by: Vladi on September 26, 2006, 01:27:59 PM

A friend's got an e36 box lying around and i've thought about it some time ago...but just didn't get to it yet. Maybe you'll do some testing and tell us what's going on. :rolleyes:

Title: E36 M42 airbox.
Post by: bullmand on September 26, 2006, 02:52:11 PM

So far the concensus is that it's a good idea. I'm working on getting my hands on the airbox. I'll keep you posted.

Title: E36 M42 airbox.
Post by: Deutschbag on September 27, 2006, 11:16:25 AM

Please do! I love the idea of more air in my engine, but I hate cone filters.

Title: E36 M42 airbox.
Post by: bullmand on September 29, 2006, 10:03:27 AM

Update on this. Below is a reply I recieved about this on another message board. This helped confirm why I think this might be a good idea. I'm still not having any luck tracking down an airbox. It looks like any of the E36 M42 boxes would work. Anybody got one lying around or know of a source? Incidentally, there's something interesting in the realoem.com parts diagram for the 1991 318i. They call the airbox assembly an "intake muffler" and they show two part numbers. One is simply "intake muffler" and the other is "intake muffler with cyclon". What's that all about?

Just a quick question for those of you who know about these things. With all other things staying the same, will an increase in the size of the airfilter result in better airflow to the engine.

Maybe. :-) What's important is the amount of air pressure decrease as the air goes through the filter. Less pressure drop = more airflow (at full throttle). Assuming filters of similar construction, a
larger filter should produce less pressure drop, and therefore, more airflow.

Title: E36 M42 airbox.
Post by: Master on October 01, 2006, 03:36:08 PM

Hmm... I own a 96' E36 318i M43, and have a much larger filter box than installed in my friend's 95' E36 M43
The M42 and M43 have very much in common, so i believe the M43 large box should fit the M42.
Maybe going to take a picture tomorrow, so you could see what i mean