M116/M117 Aftermarket Air Filter

[w1083]

I purchased a MANN air filter for my M116 3.5 5yrs ago and have since put about 20k miles on the car.

Has anyone used an aftermarket "performance" style air filter on their cars? I'd like to stay away from K&N since I don't want to deal oiling the filter after washing it, etc. Any other good air filters out there? Just want to try something other than the MANN filter I have.

[Tomguy]

I would imagine the surface area of the old style massive filters that these cars use is superior to that of a modern "Box" filter and as such, it flows more than enough air for the 3.5-4.5L of displacement. I'd be interested to see someone compare the actual physical surface area of the two, unfolded pleats and all.

If you are looking to update, you'd probably be best served trying to fit a dual-snorkel later-style filter housing on, say from a 420 or 560 w126, it would require some fab work naturally for the D-Jet centered intake compared to the KE-Jet but I would suspect the single shoehorn intake to be the larger restriction than the filter itself. Of course, it's in a great spot for (higher-pressure) cold air coming in from the front of the car and not from behind the radiator where it would be more akin to a "Hot air intake" so getting a 560 dual snorkel setup to pull from both sides of the hood would probably net the same, if not more performance, than finding a better element for the current housing - with both being superior to just sticking a "Cone" somewhere in a hot air bath area under the hood.

[w1083]

Thanks for the reply but I meant more as a drop-in/OEM replacement air filter but with slightly better performance than a MANN, etc. AEM also makes a filter that fits the M116/7 called the "Dryflow Air Filter", part number AE-10650 which I'm looking into but wasn't sure if anyone had any experience with using a different type of replacement filter for these cars.

[Tomguy]

Right, I was pointing out that on these cars, the filter isn't really a restrictive point, and I'd doubt that a "Performance" filter would offer any HP gain, perhaps adding life to the filter and that's about it.

[97 SL320]

A K&N filter is more of a rock stopper than a actual filter. OK for a track car since engines are rebuilt frequently due to accelerated wear from high loads / RPM but not so OK for a road car where long term wear is a factor.

Most of your restriction is likely to come from the air inlets rather than the filter it's self.

Have a look at this dyno test, pay particular attention to the stock dual inlet filter tests ( they tested with one blocked, both open then a lid flip. ) and the filter tested at 6:30 onward. Full results at 8:20 onward.

https://www.youtube.com/watch?v=EkpsydS8JXI

More engine testing
https://www.youtube.com/watch?v=TvQHgt-tF7Y&list=PLGvTvFzdMg_O2T3UdUEt5dIHutSOu7srE

[w1083]

Ok, so it seems that an aftermarket "performance" type air filter won't really make a difference on these cars. Looks like I'll stick with ordering another MANN filter. Thanks for your feedback guys!