K&N Filters make less noise than OEM 981 GTS
09-17-2017, 11:41 AM
#16
Not difficult but some disassembly is definitely required, I wonder if they charge a full hour of labor at the dealer for an air filter only change? I'll bet someone out there does.
09-17-2017, 12:04 PM
#17
Rennlist Member
I found it to be tedious but not necessarily difficult. Getting carpeting and panels back in just right is a PITA even if not technically difficult. Taking my time and vacuuming everything out really good took me a little over an hour, but part of that was finding the right wrenches and such on the fly. My second try would be half that, I suspect.
09-17-2017, 12:08 PM
#18
Rennlist Member
Thread Starter
FWIW, I installed K&N over the weekend and the induction noise above 4-5k is way louder. It has a sort of growl and resonance that was not present before. It sounds exactly to same to my ears at normal idle-4k rpm operation. My paper filters were very dirty at 20k miles; hard to believe Porsche specs 40k intervals.
09-17-2017, 05:25 PM
#19
Rennlist Member
09-18-2017, 01:32 PM
#20
Rennlist Member
Thread Starter
09-18-2017, 04:00 PM
#21
I don't think this is possible. My understanding of the system is that it's mechanical, not electrical. There might be an electronic valve that opens, but everything else is just another tuned tube on the intake tract which runs closer to the driver's head/ear to make things louder. Turning up the volume would involve a lot of acoustic knowledge to change the piping, resonant frequencies, and somehow amplify things further.
09-18-2017, 04:45 PM
#22
Nope, I don't. Without knowing the size of the particles and many other factors I don't think any of us can conclude either way. It seems to me that if the effect was significant at all there would be some sort of evidence as to engine wear (not just evidence as to increased dirt flow, which does exist to some degree and under certain conditions). Tiny particles get in already to no or little ill effect.
Also, to be clear, I'm not saying you're wrong and I'm also not saying more dirt particles don't cause damage or wear. I'm saying there's no evidence to support that, beyond speculation and assumption.
I do know that I've ran them for hundreds of thousands of miles in a wide variety of applications and never had an issue, and while I'm but one small data point, tens or hundreds of thousands of other folks have done the same.
Didn't mean to derail thread, so we should probably just agree to disagree and both enjoy our cars
Also, to be clear, I'm not saying you're wrong and I'm also not saying more dirt particles don't cause damage or wear. I'm saying there's no evidence to support that, beyond speculation and assumption.
I do know that I've ran them for hundreds of thousands of miles in a wide variety of applications and never had an issue, and while I'm but one small data point, tens or hundreds of thousands of other folks have done the same.
Didn't mean to derail thread, so we should probably just agree to disagree and both enjoy our cars
If the K&N filter is the same length and diameter as the OEM filter it has approximately the same surface area for air to flow through it. The only way you make more power is by flowing more air. If you have exactly the same size / shape / area of filtration then the only way you get more air through it is to offer less restriction. Reduced restriction comes in the form of reduced filtration (larger holes / pores).
I had to deal with this when I built the water filtration system for my home. Using a 20 micron filter element would give me 16 gallons per minute flow rate. Using a 5 micron filter element provides cleaner water, but limits me to 7 gallons per minute...and I have to replace the filter more often.
09-19-2017, 01:42 PM
#23
The only way you make more power is by flowing more air. If you have exactly the same size / shape / area of filtration then the only way you get more air through it is to offer less restriction. Reduced restriction comes in the form of reduced filtration (larger holes / pores).
09-19-2017, 01:55 PM
#24
Burning Brakes
No need to assume anything. One of the links I posted above has actual ISO test data.
Pressure drops across various filters were in the 4-6 in. H2O range (0.14-0.22 PSI). The difference between the worst paper filter and the K&N was about 2 in. H20 (0.07 PSI). The non-ISO test showed similar results.
The difference in flow is negligible, and absolutely not worth it (in my opinion) due to the poor filtering performance and loading characteristics of the oiled cloth filter.
"Compared to the [best performing paper filter], the K&N plugged up nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt."
Go with engineering data over marketing.
Pressure drops across various filters were in the 4-6 in. H2O range (0.14-0.22 PSI). The difference between the worst paper filter and the K&N was about 2 in. H20 (0.07 PSI). The non-ISO test showed similar results.
The difference in flow is negligible, and absolutely not worth it (in my opinion) due to the poor filtering performance and loading characteristics of the oiled cloth filter.
"Compared to the [best performing paper filter], the K&N plugged up nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt."
Go with engineering data over marketing.
09-19-2017, 05:19 PM
#25
Rennlist Member
Thread Starter
I don't think this is possible. My understanding of the system is that it's mechanical, not electrical. There might be an electronic valve that opens, but everything else is just another tuned tube on the intake tract which runs closer to the driver's head/ear to make things louder. Turning up the volume would involve a lot of acoustic knowledge to change the piping, resonant frequencies, and somehow amplify things further.
For the Sound symposium system where does the pipe take the sound from in the engine bay please ?
09-20-2017, 09:49 AM
#26
A Google search reveals that the sound symposer pipe is basically an opening through the firewall which dumps noise into the carpet / insulation behind the seats.
http://www.planet-9.com/attachments/...-gts-image-jpg
http://www.planet-9.com/attachments/...-gts-image-jpg
09-20-2017, 12:33 PM
#27
A Google search reveals that the sound symposer pipe is basically an opening through the firewall which dumps noise into the carpet / insulation behind the seats.
http://www.planet-9.com/attachments/...-gts-image-jpg
http://www.planet-9.com/attachments/...-gts-image-jpg
09-20-2017, 01:36 PM
#28
Rennlist Member
Thread Starter
thks I'm sure Porsche have thought this one through, anyone have a guide on how to remove this section of carpet behind the passenger seats on a 981 Boxster please ?