Speedtoys

"So, the K&N did not appear to harm the motor"

You -know- it will pull it more dirt (or given the mass of evidence of it, you must.., but you can say there was no harm at the same time. Those two things are in conflict with each other. A simple observation of "its ok"

One of those two things was studied and known.


No..you dont notice any issues and thats a dangerous point of view many take. They buy in about "better", even though nobody can measure it. But its all an accumulative thing too, and with only a short period of time still there, just have to tear it down and look -close- enough. Cant let silica dust regurally into the engine and expect -zero- wear.


Its no different a setup...same air that we use....an carrying the same general debris and solids in it.

Red Flash

Speedtoys, I happened to have the heads off of the 900 in 2007. Inspection revealed no damage at that time to the cylinder walls. So, that's just a simple fact.

Given your logic, I can only suppose I was driving through ultra-clean air those 2 years I had the K&N filter on the 900. Or how would you explain that then?

DKWalser

This reminds me of all my relatives who used anecdotal evidence to argue that smoking isn't harmful to your health. "Look at Great-uncle Bob, he smoked a couple of packs-a-day and lived into his 90's." Of course, the fact Uncle Bob lived a long life despite being a smoker tells us little useful about the merits of smoking; neither does the experience with ONE car that had a K&N filter installed for two years and showed "no damage" when the heads were pulled in 2007. There are lots possible explanations for for why the car showed no damage when the heads were pulled, including the possibility that it might take longer for any damage to become noticeable to the naked eye. By the time the eye can see the damage, the engine is shot....

Red Flash

I disagree with Speedtoys above. I do not know for a fact that the K&N will damage the motor. He apparently does know that it will damage the motor. Posting the source of his knowledge would help the OP!

Now David on the other hand is 100% spot on. My one anecdotal cases shows that it did not harm the motor in my SAAB over a period of about 20.000 miles, but that does not mean that it won't harm other motors in, for instance, other conditions.

I have never purported to have studied K&N filters. I also wonder, if the results can be easily transfered from my 900 to a 928 due to the mounting. Whatever the case, I would not put a K&N filter on my 928.

worf928

Speedtoys

If you have never googled for k&n filtration studies and results. Now is the time.

If you don't believe silica is a danger to an engine, please help us understand how it is not.

In any volume.

SeanR

worf928

This -^

And it's time for me to clean and re-oil both of my oiled filters. This time, I will 'punch the clock' and record how much time it takes, but my guess is at least an hour not counting R&R of both filters. I would MUCH prefer to have paper filters that I can throw away every year or two.

Petza914

With my modified cars in many I can't run the stock filter and use K&Ns. On any of them I also run a K&N hydropohic pre-filter to keep water from saturating the filter media in the rain, and on any of them that have a MAF (not the 79 928 or the dual carbed 914) after cleaning, thoroughly air-drying, then reoiling the gauze media and letting it sit to distribute the oil, I then stuff it with crumpled up paper towels and wrap around it twice with paper towels. This allows any excess oil that could damage the MAF wire be absorbed into the paper towels so the gauze only holds as much oil as it can for filtering. I've never replaced a MAF in any of the K&N equipped cars (90 Saab Turbo SPG with 250,000 miles, 2001 GMC Sierra c3 truck with 165,000 miles, 05 997 C2S with 105,000 miles, supercharged 05 C2S with 55,000 miles, & 09 Cayenne Turbo S with 30,000 miles) and do a Blackstone UOA on every oil change in each one of them. Silica levels are always single digits and below the averages they list so either the K&N is letting more dirt in but the oil filter is doing an exceptional job at capturing it where it doesn't end up in the oil sample after 5,000 miles of use, or the K&N is filtering just fine with proper care and maintenance.

If your car is otherwise stock, I don't think it will do much for you, but if you have other intake or exhaust mods and a tune where you can take advantage of the increased intake flow, then I think there are some benefits. I notice improved throttle response if nothing else, and also like the intake noise being added to the engine symphony.

Speedtoys

K&N exists, for the same reasons we have people that believe the world is flat.

Petza914

Instead of generalizations, let's put up some quantitative analysis data. Here are 30,000 miles worth of UOA data on my GMC pickup and 24,000 miles worth on one of my 997s. All of these samples were taken with an oiled K&N filter on the intake. K&N intake was installed on the truck in 2003 at 15,000 miles and on the Porsche 997 in 2013 at 45,000 miles.

Put up similar UOA reports on your vehicles running OEM airboxes with paper filters and show me how much lower the Silicon (dirt) levels are to convince me.