Got bored. Installed K&N filter.

I used a K&N filter in my Charger for a while and had UOAs done periodically to watch for elevated levels indicating more dust was getting through. I did not see any evidence of that, but after the first time I washed the filter, I did a visual inspection and did notice the act of cleaning it had created very small tears in the pleats of the filter media.

Had I reinstalled it, I am quite certain it would have allowed more dust through, but I chose not to continue running it after that.
 
Some charts I've seen suggest that the intake piping poses more pressure drop than the filter, regardless of choice. In any event, 2 in H2O pressure drop for the intake system is insignificant against 407 in H20 of atmospheric pressure pushing air into the engine.
The pressure drop is max when the throttle is WOT and engine near redline - at max airflow through the intake system (filter and tubing). I think the pressure drop of just a new air filter is more than 2 in H2O under those conditions - depending on the filter of course. Probably more like around 15 in H2O pressure drop for the entire intake system depending on the engine size (flow) and RPM. If the pressure drop could be reduced from 15 to say 7 in H2O, that would be an 8 in H2O gain which would be 8/407=2% gain. That would be ~8 HP gain on a 400 HP engine. That would be for a whole new intake system that includes the filter and intake tubing.

Flow restriction of new filters at 350 CFM. Of course the flow restriction would decrease accordingly as the CFM decreased (ie, smaller motor displacement).

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There is just about nothing that beats an intake/air filter discussion online. 99% of the folks on this site are driving average/stock vehicles and for them, use your stock intake/paper filter and drive happy. For more performance-orientated vehicles or those looking to get everything they can, an intake/high-flow filter is a great mod even if the gains are v. small most of the time. I love my aftermarket open-element intake b/c of the turbo woooshhhh and pssshhhhh when the DV dumps charge. It's worth it just for that. If anyone is interested, this fellow Jeff Jones (an aerospace engineer I believe) has done a ton of flow-bench and real world testing of various intake configs on the MK7 GTI including high-flow drop-in filters and various modifications to the stock airbox. He's done a bunch of temperature testing on all of this stuff as well. He is not looking at all at filtering efficiency. If I won the lottery I'd buy him a dyno b/c that would be so interesting!

www.mygolfmk7.com
 
There is just about nothing that beats an intake/air filter discussion online. 99% of the folks on this site are driving average/stock vehicles and for them, use your stock intake/paper filter and drive happy. For more performance-orientated vehicles or those looking to get everything they can, an intake/high-flow filter is a great mod even if the gains are v. small most of the time. I love my aftermarket open-element intake b/c of the turbo woooshhhh and pssshhhhh when the DV dumps charge. It's worth it just for that. If anyone is interested, this fellow Jeff Jones (an aerospace engineer I believe) has done a ton of flow-bench and real world testing of various intake configs on the MK7 GTI including high-flow drop-in filters and various modifications to the stock airbox. He's done a bunch of temperature testing on all of this stuff as well. He is not looking at all at filtering efficiency. If I won the lottery I'd buy him a dyno b/c that would be so interesting!

www.mygolfmk7.com

Same, my turbo sounds awesome spooling with a turbo side intake and K&N and the lovely dump charge is a classic.
 
Some people have good luck with K&N air filters and some don’t. I had a FIPK on my 06 2500hd with a 6 liter and a drop in filter installed my p71 crown vic. I have to drive through dusty gravel parking lots at work. On both vehicles the intake tubes past the air filter were completely covered with a very, very fine dust, all the way to the throttle body.

I swapped back with standard fram air filters and the tubes were spotless afterward.
 
Some people have good luck with K&N air filters and some don’t. I had a FIPK on my 06 2500hd with a 6 liter and a drop in filter installed my p71 crown vic. I have to drive through dusty gravel parking lots at work. On both vehicles the intake tubes past the air filter were completely covered with a very, very fine dust, all the way to the throttle body.

I swapped back with standard fram air filters and the tubes were spotless afterward.
That's really it I think - how much dust you are operating in. For me, it's v. little to none. The intake pipe on my Focus that is 8 years old/115K is white-glove clean with a K&N on since nearly new.
 
That's really it I think - how much dust you are operating in. For me, it's v. little to none. The intake pipe on my Focus that is 8 years old/115K is white-glove clean with a K&N on since nearly new.
I agree 100%. For a street driven vehicle that sees no dust clouds they are probably ok. Friend of mine has one on a 14 silverado and it’s clean as a whistle upstream of the filter, but he never goes off road.
 
I see the stupid under hood porsche cold air intakes. Except the porsche design actually uses outside air...and the k & n gets air 40 or 50 degrees hotter from under the hood.
So no thanks. Porsche , bmw , lexus , can all engineer a great air intake and air cleaner system .
 
The part folks seem to not get is....if you have a turbo car, that hotter underhood air makes zero difference in the air temp that hits the cylinder b/c.....intercooler....
 
The part folks seem to not get is....if you have a turbo car, that hotter underhood air makes zero difference in the air temp that hits the cylinder b/c.....intercooler....
Sure it does. If you intake hot air at 150°F from under the hood vs. 75°F air from a cold air scoop, you start with hotter air, run it through a turbo, which adds heat, then run it through the intercooler. The 150°F intake air will be much hotter coming out of the turbo and the intercooler will only remove so much heat. The end result is the cooler intake air will be cooler as it comes out of the intercooler.

Banks did a great educational video on the topic:

 
Sure it does. If you intake hot air at 150°F from under the hood vs. 75°F air from a cold air scoop, you start with hotter air, run it through a turbo, which adds heat, then run it through the intercooler. The 150°F intake air will be much hotter coming out of the turbo and the intercooler will only remove so much heat. The end result is the cooler intake air will be cooler as it comes out of the intercooler.

Banks did a great educational video on the topic:


www.mygolfmk7.com

*For my car*, the above link has more data than I've ever seen from an aerospace engineer to answer the age-old quesiton(s) about open intakes.

TLDR:

You get a ~10-15 deg temp increase of air above ambient temps to the turbo using an open intake that has a well-designed heat shield. The heat shield makes a substantial difference.

With an aftermarket intercooler, the intake air temps to the throttle body are unchanged open vs. closed intake.

The slightly warmer air to the turbo does increase the turbo's wastegate duty cycle due to the extra work to compress the slightly warmer intake air.

Aftermarket open intakes flow more air than the stock air box.

Bottom line for me with a larger turbo and aftermarket intercooler? I'm not having any adverse performance impacts running an open intake on my car. I'm getting the max flow my car can get plus all the fun of of the juvenile turbo noises.
 
With an aftermarket intercooler, the intake air temps to the throttle body are unchanged open vs. closed intake.
That's a good thing! I can imagine that most stock intercoolers have no excess capacity to cool and would exhibit an increase in exit air temperature with and increase in intake air.

Excess capacity to cool with diesels sometimes isn't a good thing. There is an optimal charge air temperature range that should be maintained. Too hot or too cold leads to problems.

I'm getting the max flow my car can get plus all the fun of of the juvenile turbo noises.
I can't hear turbos anymore without my hearing aids and when I drive I mute them so I don't have to listen to the road and wind noise.
 
That's a good thing! I can imagine that most stock intercoolers have no excess capacity to cool and would exhibit an increase in exit air temperature with and increase in intake air.

Excess capacity to cool with diesels sometimes isn't a good thing. There is an optimal charge air temperature range that should be maintained. Too hot or too cold leads to problems.


I can't hear turbos anymore without my hearing aids and when I drive I mute them so I don't have to listen to the road and wind noise.
That is correct - not much capacity left on the stock IC on my car with a larger turbo so open intake may increase IATs slightly. Eh...it's boost weather now with cooler temps here so none of this much matters anyway!
 
With an aftermarket intercooler, the intake air temps to the throttle body are unchanged open vs. closed intake.
Yep, as already mentioned a bigger more efficient intercooler will help a lot. If the intercooler is big enough and very efficient, it should cool down the air charge from the turbo to basically the ambient air temperature. The hotter the incoming air temperature, the bigger the intercooler has to be to get the intercooler outlet temperature as close as possible to the ambient air temperature.
 
Yep, as already mentioned a bigger more efficient intercooler will help a lot. If the intercooler is big enough and very efficient, it should cool down the air charge from the turbo to basically the ambient air temperature. The hotter the incoming air temperature, the bigger the intercooler has to be to get the intercooler outlet temperature as close as possible to the ambient air temperature.
I usually see anywhere from high single digits to 15 or so above ambient. 10 above is v. good on the VAG MQB turbo cars under power/boost with the popular aftermarket ICs.
 
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