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people say they lose HP when...

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Old May 6, 2009 | 08:56 PM
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warren(silver-roxy-8)'s Avatar
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people say they lose HP when...

some say they lose horsepower when they have a K&N typhoon SR intake on their car, but i just don't see how that's possible. :/
for anyone who has experience with this particular intake, what rpms are you losing HP?
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Old May 6, 2009 | 09:04 PM
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This happens because of the location of the filter. Where the filter on the K&N is located it sucks in a lot of hot air from the radiator.
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Old May 6, 2009 | 09:06 PM
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Plus the size is different and it is missing screens to stratghten out the air flow so the MAF can read correctly.
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Old May 6, 2009 | 09:06 PM
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i see...
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Old May 6, 2009 | 09:55 PM
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Originally Posted by Razz1
Plus the size is different and it is missing screens to stratghten out the air flow so the MAF can read correctly.
K&N does use 1 screen.
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Old May 6, 2009 | 10:08 PM
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hhhmmmmmmmmm
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Old May 7, 2009 | 12:04 AM
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Originally Posted by 08boostedmzda
This happens because of the location of the filter. Where the filter on the K&N is located it sucks in a lot of hot air from the radiator.
really,

have you looked at the set up?

just wondering.

beers
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Old May 7, 2009 | 12:05 AM
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Originally Posted by nycgps
K&N does use 1 screen.
as does the racing beat.

beers
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Old May 7, 2009 | 12:10 AM
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if the air intake sucks in hot air, doesn't it defeat the purpose? better off with the oem one?
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Old May 7, 2009 | 12:33 AM
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Originally Posted by Detrich
if the air intake sucks in hot air, doesn't it defeat the purpose? better off with the oem one?
if you are talking about the kn v2. you really need to see it or look at how it is located..

it gets the air from the same place from the stock intake.. and the next issue is covered by hood location..

beers
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Old May 7, 2009 | 12:43 AM
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I have the k/n V2 and the only time I notice a loss of power is 85+ degrees by then its completey heat soaked, but I just insalled a RB air duct and it works out a whole lot better.
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Old May 7, 2009 | 12:58 AM
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Originally Posted by toneskii707
I have the k/n V2 and the only time I notice a loss of power is 85+ degrees by then its completey heat soaked, but I just insalled a RB air duct and it works out a whole lot better.
really,

why and how.

beers
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Old May 7, 2009 | 01:09 AM
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Originally Posted by toneskii707
I have the k/n V2 and the only time I notice a loss of power is 85+ degrees by then its completey heat soaked, but I just insalled a RB air duct and it works out a whole lot better.
I ran with the k&N v2 for about 40,000 miles and logged intake air temperatures as high as 190 degrees when it was about 110 degrees ambient outside.

As stated, the intake requires you have all your engine panels installed to provide a seal but the problem is air still gets into the intake from the motor and most people don't run all of their plastic engine panels anyway.

As your intake air temps increase, you're robbed of power AND you also risk detonation if you're tuned with leaner air/fuel mixtures.

I've seen posts from other people that the RB air duct provides some relief from the warm air. The best method is to either go with a true CAI like the AEM or to stick with the stock intake.

While BHR hasn't had an opportunity to get hard data, it's our stance that the stock intake is more than capable of delivering the necessary flow for the RX8. If anything, you can get a drop in green or k&n filter for it.
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Old May 7, 2009 | 01:46 AM
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ahh the sound ...... im actually in the process of insulating the KnN ver 2i have. i found that majority of the heat is actually being radiated thru the bottom or whats remaining of the stock intake setup when the ver 2 is installed cuz the radiator is right under it. also, theres a gap i found and sealed which is where the VFAD duct enters the intake box, there was like a 5mm gap around the vfad duct and the stock intake box so when the rad fans are on and air is being pulled thru the radiator, some gets thru that gap and the intake temps rise. ill post pics when my whole experimental thingy is done. so far ive noticed a difference cuz the filter is a little cooler than the intake tube after a long drive now whereas before, it would be the same temp.
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Old May 7, 2009 | 03:10 AM
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when i installed mine i did feel the difference you lose low end torque but u kinda get it back in higher rpms
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Old May 7, 2009 | 11:21 AM
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Originally Posted by swoope
really,

why and how.

beers
Cuz it scoops up cooler outside air. I wish I had a temp gauge to show some numbers but sorry I don't. It just feels like it runs better with the RB duct unless your in stop and go traffic then your kinda scewed. I should of bought the duct when I bought the intake tho.
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Old May 7, 2009 | 12:00 PM
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The reason why VFAD is not good for K&N V2 is that

They position VFAD vertically, and the "opening" is right inside the fender above the oil cooler. its ok for stock intake because everything seals and thats the only opening, so if the engine "wants air", it will create a vacuum and it will only get air from there. It doesnt matter if the car is not moving or moving.

but if you use K&N with it. there is a space between the VFAD and K&N's filter. so when engine wants air, remember VFAD sits "inside" the bumper at all times and there is no vacuum because its not seal. so there is nothing there to push fresh air in. then K&N will suck whatever air thats around them. This engine needs quite a lot of air at high rpm, maybe thats why some people are experiencing lack of power with stock VFAD + K&N.

If you use RB duct with it, its opening at the front. when your car moves, the air will blow direct into it and feed the K&N filter happily.

I just dunno why K&N never thought of that. They could really design something better. or maybe make a special intake like RB Duct + AEM or something.

Last edited by nycgps; May 7, 2009 at 12:05 PM.
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Old May 7, 2009 | 12:15 PM
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I just went back to stock yesterday after having the K&N on there for a year and I noticed a huge drop in my IAT. With the K&N at idle intake temps would climb well over 100 degrees on a 70 degree day. Now they stay about 10 degrees above ambient temp with the stock intake back on.

Power wise, if the K&N gets heat soaked sitting at a light you can definitely notice a loss of power in the low RPM's up to like 4k, but it totally makes up for it on the top end. Also, once the car is moving again and air starts circulating around in the engine bay the intake temps go back down.

All I can say is that I'm going to miss the increased rotary sound and extra top end power from the Typhoon. :-(
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Old May 7, 2009 | 12:20 PM
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Just buy the aem intake
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Old May 7, 2009 | 01:35 PM
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Or just go with an RB Duct (VFAD removed), stock intake and a K&N flat filter.
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Old May 7, 2009 | 01:39 PM
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Better yet... get the RB intake and duct.
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Old May 7, 2009 | 02:50 PM
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i have a mazdaspeed cold air intake and i love it you can feel the diffrence from stock
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Old May 7, 2009 | 02:54 PM
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I like the k&n because I can hide the zex module and it makes my setup fully stealth! And it sounds good too!
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Old May 7, 2009 | 03:51 PM
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Originally Posted by nmarz77
I just went back to stock yesterday after having the K&N on there for a year and I noticed a huge drop in my IAT. With the K&N at idle intake temps would climb well over 100 degrees on a 70 degree day. Now they stay about 10 degrees above ambient temp with the stock intake back on.

Power wise, if the K&N gets heat soaked sitting at a light you can definitely notice a loss of power in the low RPM's up to like 4k, but it totally makes up for it on the top end. Also, once the car is moving again and air starts circulating around in the engine bay the intake temps go back down.

All I can say is that I'm going to miss the increased rotary sound and extra top end power from the Typhoon. :-(
why'd you go back to stock?
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Old May 7, 2009 | 03:51 PM
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warren(silver-roxy-8)'s Avatar
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alright everyone, so pretty much what i'm hearing is that it is just trial and error, cause i'm hearing A LOT of different things
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