What is the ML K&N filter part # from K&N - Page 2 - Benzworld.org

jdbower · 11-19-2003, 11:08 AM

We all know that the ML55 has the same filter as an ML320 so airflow should not be an issue. I can check later, but I think Kleemann believes that the filter can support an ML55K.

jdanish · 11-19-2003, 02:42 PM

Remember, any engine is an air pump, air in better-more power........jd

jdbower · 11-19-2003, 03:10 PM

Let's say that the air intake is a simple pipe. The amount of air that can go through the pipe is limited to the crossectional area of the smallest point (actually, there are other forces at play so this isn't exactly true - but we're simplifying here!). If the smallest area allows 10 units of volume to pass and the air filter allows 100 units of volume, replacing the air filter with one that allows 1000 units to pass does absolutely nothing.

Imagine blowing through a hole in the wall. If the hole is a pinprick you can't force very much air through and making it bigger will help. If the hole is the size of your head, making it the size of an Excursion won't make a lick of difference. Make sense?

jdanish · 11-19-2003, 04:34 PM

Ok, I have no degree in engineering, but, I have spent some time with racing engines and intake systems. I think what you fail to take into account is the restriction of the media. I also own an airplane, it has a K&N with FAA/PMA approval, and runs at a fixed RPM, so performance gains are from the lack of restriction,not pressure.
If this was not the case, why tune an intake if you only get so much air/fuel?
Over the last 30 years we dyno engines with all types of filters, all the best filters have less media/less restriction. If you have less media, you tend to increase the air flow speed [again, no degree in Physics] and that lets the MAF, and other sensors apply more fuel/air mixture.
It is also a given that for max performance, you need to increase the exhaust flow also...[new topic?]

jdanish · 11-19-2003, 04:42 PM

OK, no fair here I just noticed, jdbower, you got a supercharger, it dont matter to you! [Nice set up by the way]
My GMC has a 4.3L V6, with a turbo, dont matter what you put on the end of the pipe, got to talk boost pressure, I can get around 16" with a mod chip, what are you getting?

jdbower · 11-19-2003, 07:42 PM

If you want to talk restriction, think about blowing through cloth. A very fine weave is very restrictive. Something like cheesecloth is not. Replacing the filter on an ML for HP gains is like going from cheesecloth to fine netting. Yes, there is a small increase in airflow, but not nearly enough to make a real difference. By not using MB approved stuff you're voiding your warranty on associated components (MAF, etc.) for MAYBE one or two HP. Even if you're convinced that the new filter is just as safe there is a risk that the device will fail anyway. You also have to think, if these filters are so much better why doesn't the manufacturer use them? Cost savings? How about in the ML55? An extra few HP is worth a lot more than a few bucks for a filter in marketing terms.

jdbower · 11-19-2003, 07:50 PM

If you put a restrictive air filter on a super/turbocharged engine you'll lose power.

About the boost amount, I should be getting about 0.5 bar (convert to whatever units you want here: http://www.ex.ac.uk/cimt/dictunit/ccpress.htm)

Don't mean to argue, just want to point out the risk reward so people can make an edumacated decision[:D].

tcp_ML500 · 11-20-2003, 06:41 AM

improve performance when swapping the MB filter to a K&N air filter.

I live for theory, but I love dyno curves (a before and after picture using the same vehicle and equipment all around safe for the air filter).

And now on to the Cliff Clavin special:

Igor Sikorky was once told before he built his first chopper that from an aerodynamics' perspective, helicopters could not take flight.
His answer:
"Bumble bees are not aerodynamically sound and should not be able to fly. But the bumble bee ignores that fact, and hence, it can fly!"

Another version:
"The flight of the bumble bee was not scientifically feasible until the last few years? I could have swore I saw them flying in my youth! "

jdanish · 11-20-2003, 08:49 AM

Jeff, great discussion, not sure I can run my ML on a dyno, or the Typhoon either, AWD dynos are hard to come by here in the Northeast.
I understand the case for reduced filter performance, and the warranty issue. You should also know we run a repair shop. We deal with this every day, and , some products fail, some last longer than OEM.
I often wonder how many ML's are out there running on other than 0W-40 Mobil1. Trust me, other items changed on the ML can adversly affect the performance way more than the air filter.
[oversize wheels-gear ratio?] Vehicle speed sensor reaction? Still like your setup for modification best!
jdanish

tcp_ML500 · 11-20-2003, 08:57 AM

Quote:

Trust me, other items changed on the ML can adversly affect the performance way more than the air filter.

Is that a good reason to make the water muddier than it already is, especially given the dubious gains?
Is that the best argument for going K&N?

You should also know that even though I don't run a repair shop, you can trust me on this one, a Kleemann blower will positively affect the performance way more than a K&N air filter.