I just bought a used M2 cold air intake box,aluminun old style without the filters. Could someone check there's and give me an kn filter model ,or part #? thanks in advance,called m2 and got a recording...

 

Don't know the exact part number, but pretty sure they use 'universal' K&N filters. Lots of sizes though, but given that you can measure the dimensions in the box and the intake pipe diameter, you can pick the filters you need here:

http://www.martelbros.com/cgi-bin/st.../universal.htm

I ordered one for my Apexi single turbo, as that my IC pipe did not let me put the Apexi filter on (both occupied part of the same space).

Based on my old RX7 Fashion box (same basic shape), you'll likely need one filter with a angled neck (for the top inlet pipe), and the other straight.

http://www.martelbros.com/cgi-bin/st...nivrndstrt.htm

 

RB-0720 is the K&N part number (although the number on the filter itself will be different..F025A4 I believe)..verify that this is a universal 2.5" filter.

 

Ok, Martel Bros' has a funky site.

Go to: www.martelbros.com

- Click K&N logo in the center window
- Click 'Universal Air Filters' on left menu
- Scroll down and click Round Straight

They do have a neat floating item number search function. The number that Aristo gave comes up as a 2.5" intake neck diameter with a 5 degree angle.

 

Thanks for the help ! I was curious what M2 used. I had already been to the martel site and decided one could get away with the 2 7/16" mounting hole because they say they will stretch 1/16" this opens up alot more choices then the 2 1/2" chart and a tight fit couldn't hurt.I also came to the conclusion ,as you did that the top one should ,or could be angled and the bottom staright. Also if i went with the oval design i could get some really big honkin ones in there.