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Discussion Starter #1
Merry Christmas!

Sorry if this is a dumb question.
Anyway, I've had a 2016 ST for about a month. I put in a green filter the 2nd week I had the car. (I had the lid off for a few days but then put it back on)
I read somewhere on here that someone had a green filter and he got dirt in the motor or something, and even after putting the stock filter back on, Ford wouldn't honor the warranty?
I see so many people use the green filter, so I'm not too worried...but of course, after reading that about this guy, it was slightly concerning.

The other part of my question is about the resonator delete. Can this harm the motor? Or burn out the cat?

I tried searching but didn't find info on these questions.

So for those of you who have either/both of the mods, what is the length of time/miles you've driven?
Thanks!
 

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Not really.
There is some debate weather the Green filter (or any non-OEM filter) meets the OEM's specifications.
I think I read the same thread, and the guy had many other modifications that could have caused the engine failure.
 

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If you let in more air, with out proportionally increasing surface area, you let in more dirt.

Stock filter should be more than adequate for any bolt on / tune job.
 

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I think this has always been more of s oiled vs dry filter instead of stock vs aftermarket debate. The consensus is usually that oiled filters flow so much better at the expense poor filtration. A lot of info and skepticism out there on how bad oiled filters are.
 

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You may reduce a little torque for the resonator deletes I just had mine removed a week ago and and haven't had any issues

Sent from my SM-G930T using Tapatalk
 

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I replaced my resonator with a magnaflow muffler and did a stock muffler delete about 2 1/2 years and 57,000 miles ago. Green filter was shortly thereafter.... If it was going to cause issues I think it would have happened by now.
 

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I have an oil analysis showing sharply increased silicon in the oil after switching to a properly oiled K&N panel filter on my old '95 Taurus SHO. It was there for two samples until I went back to the stock filter and silicon immediately dropped down to previous levels.

Silicon in an oil sample indicates sand/dirt getting through the filter. If it makes it into the oil, that means it went through the cylinder first. Almost all other wear metals (tin, steel, lead, aluminum, brass) went up very slightly during the two samples I was running the K&N, then went back down after switching back to the stock filter, indicating that the ingested dirt/sand was causing accelerated engine wear. Not much, mind, but it corresponded with the increased silicon.

I have not run an aftermarket filter since. Any perceived benefit simply does not offset the increased engine wear due to poor filtration.
 

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I believe there was some talk about this a week or so ago that the stock air filter is more than adequate. It's the same filter that the RS uses so it flows plenty of air (350 HP) and filters out more dirt. I live in the dusty ass desert so I'm sticking with the stock filter.
 

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Haven't had the ST long enough to comment on the long term effects of the Cobb/Green filter on the engine, but I've run K&N filters in my previous cars long term with no ill effects. I doubt it will have any more impact on my engine than the tune I'm running.

As far as the resonator, it's after the cat so you have nothing at all to worry about. Butt dyno shows no change in performance at all. Ear dyno says res delete with a Green filter sounds pretty good.
 

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I have an oil analysis showing sharply increased silicon in the oil after switching to a properly oiled K&N panel filter on my old '95 Taurus SHO. It was there for two samples until I went back to the stock filter and silicon immediately dropped down to previous levels.

Silicon in an oil sample indicates sand/dirt getting through the filter. If it makes it into the oil, that means it went through the cylinder first. Almost all other wear metals (tin, steel, lead, aluminum, brass) went up very slightly during the two samples I was running the K&N, then went back down after switching back to the stock filter, indicating that the ingested dirt/sand was causing accelerated engine wear. Not much, mind, but it corresponded with the increased silicon.

I have not run an aftermarket filter since. Any perceived benefit simply does not offset the increased engine wear due to poor filtration.
This ^^! This is what I like to refer to as facts, or conclusive evidence, or whatever your favorite term is. Statements like "I've never had a problem" having never done anything substantiating are pointless. I've been on several auto/motorcycle forums over the years and this is what you always see from K&N and other oiled filter users when they take the time to do proper research. There is nothing wrong with aftermarket filters as long as they're dry. Want a good aftermarket filter...look at AEM.
 

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Discussion Starter #14
I have an oil analysis showing sharply increased silicon in the oil after switching to a properly oiled K&N panel filter on my old '95 Taurus SHO. It was there for two samples until I went back to the stock filter and silicon immediately dropped down to previous levels.

Silicon in an oil sample indicates sand/dirt getting through the filter. If it makes it into the oil, that means it went through the cylinder first. Almost all other wear metals (tin, steel, lead, aluminum, brass) went up very slightly during the two samples I was running the K&N, then went back down after switching back to the stock filter, indicating that the ingested dirt/sand was causing accelerated engine wear. Not much, mind, but it corresponded with the increased silicon.

I have not run an aftermarket filter since. Any perceived benefit simply does not offset the increased engine wear due to poor filtration.
That being said...I'm probably going to sell the green filter with the couple hundred miles I've put on it - and go back to stock.
Anybody interested?
 

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I took the liberty of locating the oil analyses in question - they are from much further back than I thought! - and have uploaded them.

View attachment D49770.pdf

View attachment D67767.pdf

It seems time has somewhat dulled my exact recollection of events - only one sample passed between installing the filter and removing it - but take a look at the PDFs and form your own opinions.

I'm not telling you to not use whatever filter makes you happy. This is 'Merka, etc. I'm just showing a little bit of empirical evidence to show that higher-flowing filters with identical surface area will allow more contaminants through.
 

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This ^^! This is what I like to refer to as facts, or conclusive evidence, or whatever your favorite term is. Statements like "I've never had a problem" having never done anything substantiating are pointless. I've been on several auto/motorcycle forums over the years and this is what you always see from K&N and other oiled filter users when they take the time to do proper research. There is nothing wrong with aftermarket filters as long as they're dry. Want a good aftermarket filter...look at AEM.
Keep in mind that just because they are dry, it doesn't mean they filter well. Take a look at this scientific test:

ISO 5011 Duramax Air Filter Test Report

Pretty much tells you all you need to know about the filtration capability of an oiled gauze filter (K&N/Green/etc.). I have an oiled gauze filter on my vette, but to make 600rwhp on its N/A motor, you have to pull out all of the stops. I do change the oil much more frequently than I would on my daily ST. I will be keeping the stock filter on the ST. IMO, its flow is sufficient until you move to a big turbo, and only then is an "upgrade" potentially needed. If you want the noise, get a Roush or RS lid, and keep the stock filter.

As to the warranty...Ford was refusing turbo warranty coverage on the 6.0L diesels that had aftermarket air filters on them, back in the day. Not sure what their position is these days with the 6.7. They were stating that excess dirt was wearing the compressor wheel, causing increased turbo RPM, which contributed to a catastrophic failure of the turbo. With that said, the early 6.0s were notorious for turbo failures anyway, so who knows if the filters were really a problem or not.
 
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