Project E39 M5: K&N Filters and HPS Intake Hoses


The HPS Performance Parts intake hose kit was designed in-house and is intended to be a direct fit. Notice the hoses are not symmetrical. The OE design uses a slightly shorter hose after the bend on the driver side hose.


Removal of the OE intake elbows is not very difficult either. Worm screw style clamps hold both ends of the OE intake elbows. When removing the intake elbows be sure to remove the MAF/Intake-temp sensor wiring that runs on the bottom of the OE elbows.


When you remove the elbow you'll probably have a bunch of gunk surrounding the entrance to the plenum. Clean all of it off and make sure it does not get inside the plenum. 


These rubber seal rings must also be removed before you can install the HPS silicone hoses. Ours probably have not been moved since the car came off the assembly line so we needed to use a little persuasion to take them off.


The OE intake elbow is hard plastic and is corrugated in some areas. For the most part the diameter of the OE intake elbow is 70mm, but in some areas the OE intake elbow necks down to 65mm.



  1. Hi Martin, and Mike,
    I love that fact you guys are doing a project E39 M5, as I’m working on mine as well. This intake article is very interesting, and would also like to see if you’d be interested in (dyno) testing another intake (AFE) that’s very easy to swap on. My E39 M5 came with it when I bought the car, and in design, it looks like it makes sense… very similar to the silicone hose + K&N setup you tested. Except, mine my AFE has a hard molded, smooth pipe and runs cone (K&N style) filters. Would you guys be interested in testing this setup as well? I am in Torrance, and the swap would take 5 mins. Please let me know if this is possible~

    *Reason I ask is, the AFE kit seems to have a negative gain on performance for the S62, based on an old dyno run someone did years ago. Looking at the design, I don’t understand how it could be worse than stock. I recently dyno’d my car and numbers weren’t bad. Wondering how it fares compared to your setup. -Thanks~

    1. Hi Joe,

      Thanks for reading! We’ve actually been wanting to test the AFE intake too. We’ll reach out to AFE to see if they would be interested in supplying us with one of their intakes for another test. We think that would be great info for the E39 M5 community to have!

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