K&N intake system
Thread Starter
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
K&N intake system & drop-in replacement filter
Part # 63-3120
https://www.knfilters.com/63-3120-pe...-intake-system
***9/24/21 edit***
K&N has now released their drop-in filter for the C8 as well:
part # E-0636
$99.99
https://www.knfilters.com/e-0636-replacement-air-filter
https://www.knfilters.com/63-3120-pe...-intake-system
***9/24/21 edit***
K&N has now released their drop-in filter for the C8 as well:
part # E-0636
$99.99
https://www.knfilters.com/e-0636-replacement-air-filter
Last edited by Kracka; Oct 1, 2021 at 10:50 AM.
Le Mans Master
Joined: Jul 2000
Posts: 6,559
Likes: 4,501
From: North Dallas 40 TX
It is interesting that the biggest gain is claimed to be 22HP at 5000 RPM, but the peak HP gain is less than half that. It is an indicator that peak flow improvement is about 2% maybe. I am not as big a fan of oiled cloth filters as I used to be, after there have been problems with MAF sensors being damaged. Likely from over exuberant oiling, but it can be hard to tell what the optimal amount is.
I also wonder how much difference the gear used makes. They used the same in both, so comparable for gains, but curious on the impact on total HP.
Since it changes more than the filter, I wonder if it fits the HTC as well.
I also wonder how much difference the gear used makes. They used the same in both, so comparable for gains, but curious on the impact on total HP.
Since it changes more than the filter, I wonder if it fits the HTC as well.
Pro
Joined: Nov 2013
Posts: 545
Likes: 245
From: Lower Burrell PA
Below are a few links demonstrating that Green Filter flows more air than the competition. I've installed one in my C8-Z51 and it fits perfectly. It also resulted in a little more intake sound if you are driving with the windows down.
Green Filter #7382 - https://greenfilter.com
See: https://www.summitracing.com/search/...er-color/green
And: https://store.greenfilter.com/products/7382
Green airflow demo video #1:
Green airflow demo video #2:
This video shows dyno proof of K&N performance gains vs paper filters. Of course based on the above airflow videos, the Green filter would theoretically have equal or greater results:
Green Filter #7382 - https://greenfilter.com
See: https://www.summitracing.com/search/...er-color/green
And: https://store.greenfilter.com/products/7382
Green airflow demo video #1:
Green airflow demo video #2:
This video shows dyno proof of K&N performance gains vs paper filters. Of course based on the above airflow videos, the Green filter would theoretically have equal or greater results:
Last edited by copjsd; Aug 5, 2021 at 12:52 AM.
Le Mans Master
Joined: Jul 2000
Posts: 6,559
Likes: 4,501
From: North Dallas 40 TX
The green filters website is terrible. It is an oil cotton filter like K&N filter. It even has a similar vibe to the logo, except in green. And neither it, nor K&N show comparative filtration testing to OEM filters.
The other thing to consider is that higher air flow in a filter at a given level of vacuum does not always mean more power. If say the OEM filter flows 800 CFM at 1 inch of vacuum, and the aftermarket Filter flows 1000 CFM at the same vacuum it won't help much if the engine only flows 400 CFM at that manifold vacuum.
I wish filter manufacturers would show filtration comparisons.
The other thing to consider is that higher air flow in a filter at a given level of vacuum does not always mean more power. If say the OEM filter flows 800 CFM at 1 inch of vacuum, and the aftermarket Filter flows 1000 CFM at the same vacuum it won't help much if the engine only flows 400 CFM at that manifold vacuum.
I wish filter manufacturers would show filtration comparisons.
Thread Starter
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
Le Mans Master
Joined: Jul 2000
Posts: 6,559
Likes: 4,501
From: North Dallas 40 TX
I like this from AFE: https://afepower.com/air-filter-media
Other interesting things. The air flow of the stock replacement Pro5R filter is 725 CFM at 1.5" of vacuum. versus stock at 525 CFM Good increase.
The Black and Track series duel cone systems say they flow PRO5R media flow at 605 at 7" of vacuum , versus stock 525 CFM at the same vacuum. Less than the replacement filter at much higher vacuum which should flow more than lower vacuum. Plus it shows no change in flow for the stock filter at the higher vacuum, which bodes not make sense. One has to wonder why they chose to show flow testing as significantly different vacuum levels, and why no change in stock filter at higher vacuum. Also no Dyno chart for the replacement PRO5R filter?
What companies choose to tell you, and what they don't tell you is always interesting. I get putting you product in the best light, but it makes you go hmmmmmm, to quote and old Mazda ad.
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Instructor
Joined: Aug 2008
Posts: 220
Likes: 111
From: az
i am sure K&N will give you extra power in the beginning, as time goes by the gain will disappear as the cylinder walls get scratched from all dirt getting by these type of filters.
https://www.nicoclub.com/archives/kn-vs-oem-filter.html
https://www.nicoclub.com/archives/kn-vs-oem-filter.html
Le Mans Master
Joined: Jul 2000
Posts: 6,559
Likes: 4,501
From: North Dallas 40 TX
i am sure K&N will give you extra power in the beginning, as time goes by the gain will disappear as the cylinder walls get scratched from all dirt getting by these type of filters.
https://www.nicoclub.com/archives/kn-vs-oem-filter.html
https://www.nicoclub.com/archives/kn-vs-oem-filter.html
Burning Brakes
Joined: Aug 2007
Posts: 817
Likes: 461
Based on the cost of C8 aftermarket parts, adding the term “C8” to product packaging must cost a small fortune.
As for me, I am fine leaving everything stock until prices get more reasonable. The cost for the small amount gains just isn’t worth it.
As for me, I am fine leaving everything stock until prices get more reasonable. The cost for the small amount gains just isn’t worth it.
Thread Starter
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
K&N has now released their drop-in filter for the C8!
K&N part # E-0636
$99.99
https://www.knfilters.com/e-0636-replacement-air-filter
K&N part # E-0636
$99.99
https://www.knfilters.com/e-0636-replacement-air-filter
Last edited by Kracka; Oct 1, 2021 at 10:51 AM. Reason: updated price & link
Le Mans Master
Joined: Jul 2000
Posts: 6,559
Likes: 4,501
From: North Dallas 40 TX
K&N has now released their drop-in filter for the C8!
K&N part # E-0636
$63.99
https://www.knfilters.com/chevrolet/...l-v8-gas/2021/
K&N part # E-0636
$63.99
https://www.knfilters.com/chevrolet/...l-v8-gas/2021/
Thread Starter
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
They posted the air flow data which I've attached. Most companies don't post performance gain with their drop-ins to push you towards their full intake system. AttackBlue is the exception here, but AFE and K&N both share this marketing strategy. Overall, the data shared by K&N in the attached is far more comprehensive than what AFE shares and is actually quite interesting. I'll likely order one since it's only $63.99 so I can compare it vs. my current AttackBlue first hand. I'm still convinced all the gains the full intake systems are seeing are from the air filter alone and my hypothesis is any of these good aftermarket performance filters alone will see similar gains at only 10-20% of the cost.
Racer
Joined: Jul 2010
Posts: 293
Likes: 60
From: Wheatley Ontario
They posted the air flow data which I've attached. Most companies don't post performance gain with their drop-ins to push you towards their full intake system. AttackBlue is the exception here, but AFE and K&N both share this marketing strategy. Overall, the data shared by K&N in the attached is far more comprehensive than what AFE shares and is actually quite interesting. I'll likely order one since it's only $63.99 so I can compare it vs. my current AttackBlue first hand. I'm still convinced all the gains the full intake systems are seeing are from the air filter alone and my hypothesis is any of these good aftermarket performance filters alone will see similar gains at only 10-20% of the cost.
Thread Starter
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
Instructor
Joined: Jun 2012
Posts: 169
Likes: 69
Air Cleaner Center Web
I have an aFe Pro 5R filter in my 2021 C8 Z51 and noticed that it does not have the center divider web of the stock C8 air filter as well as the K&N filter. What is the purpose of the center web? Does it help to turn the incoming left and right air flows to assist laminar flow to the IM?
Thanks, Bill
Thanks, Bill
Racer
Joined: Jul 2010
Posts: 293
Likes: 60
From: Wheatley Ontario
I have an aFe Pro 5R filter in my 2021 C8 Z51 and noticed that it does not have the center divider web of the stock C8 air filter as well as the K&N filter. What is the purpose of the center web? Does it help to turn the incoming left and right air flows to assist laminar flow to the IM?
Thanks, Bill
Thanks, Bill
Thread Starter
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
I have an aFe Pro 5R filter in my 2021 C8 Z51 and noticed that it does not have the center divider web of the stock C8 air filter as well as the K&N filter. What is the purpose of the center web? Does it help to turn the incoming left and right air flows to assist laminar flow to the IM?
Thanks, Bill
Thanks, Bill
Here's some internal shots of the Attack Blue air filter vs. OEM:
Last edited by Kracka; Oct 5, 2021 at 10:51 PM.
