BubaE350

Here's one for you gear heads... K&N make a great product, I've used them before and loved them in the past. Most of my experience was with carbureted engines. In general the harder you stepped on the accelerator pedal the more air and gas would go in the intake. Does a K&N filter really raise the advertised up to 10 horse power rating, even though the air mass censor controls the amount of going through the throttle body on a stock engine? If the the car's parameters are altered to accept more air, then would the K&N filter make sense? Am I right?

kajtek1

Fixed it for ya.

aquinob

10%? Not that I ever heard. If you can wade through this article, it shows that you get a very marginal increase over stock OEM filters, but they conclude they aren't worth the added cost.

sturitter

You will definitely have 10% more dirt drawn through your engine. Every K&N equipped engine I've worked on had grit on the throttle plate/air mass sensor/etc.

Stu

VegasE

There is an article somewhere on the internet where someone measured the dirt passed through several aftermarket filters and K&N was the worst by far. The number was several times more dirt than an OEM. I've seen enough dyno tests to believe a K&N might give you a few more HP but the amount of junk going through your air system is not good for your engine. Dyno tests are nearly impossible to replicate because the results depend on air temperature, engine temperature, and several other factors so differences of a few HP are common. Most amateur dyno tests I've seen have the K&N as the second test which means the engine is now hotter than the first test and will generate more HP.
Do you think that MB would waste millions of Euros in research trying to get a few HP from an engine if all they had to do was change air filters? I'm convinced the "seat of the pants" increase in performance most folks experience is only in their head, same as a car seems faster after you detail your car. The OEM air filter is designed to get the most air possible without inhaling a load of dirt. Stay away from K&N and similar high volume high dirt "filters".

kajtek1

What always amaze me is how young folks buy the "cold air system" K&N advertise, when in fact most of those systems suck hot and dirty air from engine bay.
Can't fix stupid

VegasE

.

Mud

I use inexpensive Pentius air filters (Rockauto) for all our vehicles over thousands of miles. Once yearly oil analysis never indicates any sort of increase in silicates or other compounds ingested from the air intake.
Throttle body is never excessively dirty either. Real time scan data confirms short/long term fuel trims exactly where they need to be. For me this is realistic data so I'm happy with the air filter choice. All our vehicles also use stock air box and intake air routing.

I had posted this on another thread, I've also confirmed a couple more times on other vehicles. The cone filter I referred to was some sort of mesh looking garbage, I can't say it was K&N, probably an ebay copy.

Last year I tried to show my ditz neighbor why his cheap aftermarket "cold air intake" caused his car to perform worse not better.
It was just sucking in underhood air, and the aluminum tube acted like a big heat sink. I hooked up my scanner to show real time data. This was in Texas late summer.
Stock airbox and inlet IAT temp 96d F
Aftermarket air intake IAT temp 134d F
MAF sensor gm/sec reading increased with cooler air inlet temps, I figured due to denser air.
Short term fuel trim range also increased with the after market intake, I took it to be due to a leaner condition. I doubted the cone filter flowed any better than a good quality stock paper filter.
It was actually a hot air intake that made more noise.

cetialpha5

Not only that, but the oil from the filters tend to coat various sensors like the MAF sensor and then you have to clean it or you get problems. They may have made sense in the past, but not for today's engine.

They're more trouble than they're worth, no one bothers with them anymore.

kajtek1

If they made sense in the past, that could be only due the fact the owners did not expect engines to last past 100k miles.
You want performance and don't worry about engine life?
Make straight pipe from the hood like this guy. Who needs filters?

jonUF02

I've had K&N in my 550 M278 for about 25K miles now. FTW!

Probably time to take them out and do a cleaning.

VegasE

Here is the article https://nicoclub.com/archives/kn-vs-oem-filter.html
Go to the Accumulative Gain chart which shows the K&N passing through almost 20x more dirt than an AC Delco.
Using something other than the OEM or equivalent air intake and filter on an engine is bad for the engine (due to dirt ingestion), however, if you do engine performance mods, increased HP requires increased air flow so you need to redesign the air intake but I would not use K&N even then.

2006C230V6

It's not going to make it run better. And it may make it run worse. From my experience, I would not use one again.

Jan AMG

I've had two similar CLS63S. We did many drag runs - always the same. We installed K&N in one car and repeated. The result = no change.

Mr.Fly

LOL, those apex seals will probably need to be replaced before dirt ingestion cause serious problems.

cx876

had them in my SLK, it was all fun and games until my intake manifold toasted after 8 months,
I don't know man, but I ain't doing that again.