luxury1

One of my friends bought a K&N air filter for his car. It is supposed to give you ten more horses and better fuel economy. Has anyone else done this? Would you recommend it? Will it void the warranty?

bmms8

i highly doubt it will void the warranty, but you never know. Epower i believe has k&n filters, because there are two i believe. i think getting a new pulley would be a lot better, but thats just me. GL with your decisoin.

Harris

Changing the air filter can NEVER give you 10hp gain. In fact, it will NOT give ANY hp gain. HOWEVER, more air does flow into the engine and air does flow better into the engine.

IMO, BMC is a bit better than other brands.

phahn

I put in a k and n air filter on another car I owned (not MB) and it did seem to make a differance. In fact over time it got even better. I don't know how it worked but I did seem to have more power, or I should say smoother acceleration. I was thinking of doing the same with my E 500. A question is how do you get too the air filter, how does the plastic cover come off?

luxury1

How you get to the air filter is a very good question. Yesterday I was able to change the bulbs though to match the xenon's so I feel I am making way in the mechanical world

I am surprised to hear that I hear an up and down review on the filter. I guessed that all I would hear would be up... Harris, what gain will it give me???

LIONHEAD

I did get the K&Ns after looking at Epower's post and also replace the driver side snorkel tube to the S Class. Like Harris said, you won't see any HP gains. In fact, most performance Bolt On Mods these days won't give you much RWHP (if any) unless you go under the knife with the engine. Also...remember if one Bolt On claims (lets say larger Throttle Body) 5 RWHP and another claims 8 RWHP (lets say Ported MAF) doesn't mean you will get 13 additional RWHP combined.

amgkoo

I replaced the filters with K&N on my E500 cuz that's just a basic mod that I have to do. I am still breaking in the car so I don't know if it has made any difference. I didn't feel much gain in performance after I put in the K&N in the ML500 and E430. But the throttle does feel more responsive on the freeway. I would say that aftermarket air filters probably only make a decent amount of HP improvement on turbocharged or supercharged cars.

jyg e500 maybe

oil used on K&N can foul airflow sensor. It can cause erratic idle/ it did so on my 2000 bmw/ and K&N will allow larger particles in than stock paper filter.

BoSoxFan

Sincere question: Am I missing something here? According to Harris, there is NO HP gain but air flow is improved. So what? What is the point of doing it if there is no measurable performance improvement?

Stricks

If you think of a car as a person, then you will see what is going on. You need to be able to take in air and expell it. And the more efficiently you do this the better. The more efficiently your body burns fuel, the better it will perform. Better shoes on the runner will help the runner run better. And so on. Changing the air filter and the air tube is just a very simple and cheap expenditure. The results won't be noticed on the gas pedal, but they are probably there to some degree.

phahn

Lionhead, I love your front grill, can you share where you got it? I am also still looking for the trick to taking off the plastic engine cover to change the air filter.
thanks

BoSoxFan

Sure, that's all basic physics. Increase the O2 until you get to some optimum fuel-O2 mixture which is going to result in maximum power (i.e., HP) for a given amount of fuel and combustion technology. But, if you are not getting an increase in power (i.e., measurable HP), then maybe you are already at that optimum ratio. Now, if it makes you THINK that you are getting more power, then that's a different story.

Davel

Couldn't resist, here's my .2 cents. I've used K&N filters on and off for about 15 years on motorcycles and cars. K&N developed a reputation in the racing community and is still considered 1 of the best. As far as non-racing cars, personally I've used them to save money, either by not having to replace another paper filter (costing $20 - $40 sometimes) or to save labor costs on hard to get-to motorcyle air filters. As far as HP increase there will be an increase as represented on a DYNO, but not seat of the pants. While the K&N does flow more air, its the volume of air that makes a diffrence as in race cars, so a larger air-box with a K&N would give you a noticeable increase in power. CAUTION: In the BMW community there were many reports of the oil used in the K&N filters destroying the air flow sensor(s).

BoSoxFan

Now that makes sense. If the dyno shows an increase in HP, then there is a benefit to the different filter. Sorry if I sounded like a wisea--; just trying to figure this out.