A4 air box

[djminkin]

Hello can anyone help me with the correct size and brand of the rectangular air filter that goes in the alpina a4 air box?  Thx

[Simeon]

Some discussion here. Looks like it is an e21 part. 

 

 

[djminkin]

Thanks. That is the black one. I prefer to find the one with the thicker orange rubber around it. 

[markmac]

The air filter element was made by Purolator (the key word here is "was"), NLA now for a long time unless somehow you find one ratpacked away on someone's shelf.  My understanding is that there is a K&N filter that is close, requires some surgery with an exacto knife but apparently works.  Several on this board run those so one of them my chime in with what they are using.  You could reach out to Cahsel in Germany, he may have one/some.  Good luck

Edited March 20, 2017 by markmac

[djminkin]

Thanks for the info. Maybe someone can chime in and tell me what filter they are using. 

[John_in_VA]

Most of the air filters I've purchased from the BMW dealers have had an orange edge - E28, E46 and E39 most recently.  Perhaps the E21 filter comes that way.  ECSTuning.com shows the E21 Mahle & genuine BMW filters with the orange edge.

 

 

[djminkin]

Thanks. But which one works?  

[Simeon]

Rock Auto has the A34762 in stock for about $4.50. It might be worth a shot. 

[downhillwolf]

Get yourself a custom made out of foam. I'm sure ITG firm from UK really has ears for classic cars. You can also try pipercross.
Foam filters are multiple use and better flow. But they are quite expensive...

[markmac]

These Purolator filters are NLA as I mentioned, see below link for a possible K&N option, this is probably your best option.  Good luck.

http://www.e21-board.de/wbb/forum/forum/51226-luftfilter-gesucht/

Take a K+N Filter produced for Alfa-Romeo 75 with the 3,0l engine and a
cutter knife.
Look at the pictures,
The K+N Number was 33-2545.