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Discussion Starter · #1 ·
Running Bluefin stage 1 and if all goes well i'll be putting stage 2 on wednesday with uprated intercooler.

Just fitted a K&N panel filter and car feels slower, is there a reason for this loss of power? Just doesn't pull as much as when the oem filter was fitted and feels a tad jerky.
Maybe the ecu has to relearn due to the extra air flow. Any help would be appreciated.
 

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Put the old filter back in and see what happens. Also air temps seem play a big part in how the car performs sometimes I go out in mine and I'm like woohoo it's fast and then go out again a few hours later or the next day and it feels slow.
 

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Discussion Starter · #3 ·
Put the old filter back in and see what happens. Also air temps seem play a big part in how the car performs sometimes I go out in mine and I'm like woohoo it's fast and then go out again a few hours later or the next day and it feels slow.
Put the stock one back in and powers back, strange thats why i thought the ecu may have to adapt.
 

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Odd. I found the K&N panel gave slightly better throttle response and seems to work well with the bluefin. Strange stuff.
 

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You shouldn't notice a difference either way mate. The filter is not the restriction. There is a restriction after the filter which already lets the maximum amount of air through. You could run with no filter and still have the same airflow.

Also, Gary (collins) has told me in the past that ramair conducted tests a few years ago and the oem filter slightly outperformed the aftermarket ones
 

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Discussion Starter · #6 ·
You shouldn't notice a difference either way mate. The filter is not the restriction. There is a restriction after the filter which already lets the maximum amount of air through. You could run with no filter and still have the same airflow.

Also, Gary (collins) has told me in the past that ramair conducted tests a few years ago and the oem filter slightly outperformed the aftermarket ones
So you could run stage 2 with oem filter and you wouldn't lose power?
 

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Maybe give it a few days and see how it goes.

So you could run stage 2 with oem filter and you wouldn't lose power?
You wouldn't add any power with an aftermarket one. The std intake system is capable of providing sufficient air flow of up to 300bhp
 

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You wouldn't add any power with an aftermarket one. The std intake system is capable of providing sufficient air flow of up to 300bhp
While this is true, it is much easier for the engine to draw the air it needs from an aftermarket system
 

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The OEM filter is a large pleated one, a foam or cotton one is flat and has less surface area, but is not flow restricted in the material itself, so will give throttle response improvement, but not extra power. A half blocked OEM filter would likely still pass enough air for a stock ST to operate to spec.

The whole issue of stock airbox versus CAI is all about flow efficiency and reducing bottle necks to allow a big map to push a well modded car as far as possible, but yes, you need plenty of mods to actually get the desired gain from a CAI. There will always be throttle reponse gains though. That air box has more twists and turns than an Agatha Christie novel.
 

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Discussion Starter · #14 ·
You wouldn't add any power with an aftermarket one. The std intake system is capable of providing sufficient air flow of up to 300bhp
Are you saying the OEM filter is good upto 300bhp? Or do you mean the airbox is capable of providing airflow upto 300bhp?

A bit confused to which is correct.
 

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Discussion Starter · #17 ·
Just feels flat when you put your toe down, strange. Maybe stick with the OEM filter.
Drove around 30 miles and still flat as a fart, so hoyed the K&N out and refitted the OEM one and presto full powers back. Don't know whats going on but theres definitely something not quite right here. Even let the wife drive to see if she could notice the difference between the two and she felt as if the turbo had been nicked when the K&N
was fitted.


K&N panel filters are a load of
! Will not be wasting any more cash on them in the future.
 

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That´s strange. I have a k&n replacement filter, and never had any issues. The filter has been washed and re-oiled some months ago, and the car still goes strong. I don´t apreciate any power gain with it, but it makes a little more whistling noise when accelerating.
 

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Discussion Starter · #19 ·
That´s strange. I have a k&n replacement filter, and never had any issues. The filter has been washed and re-oiled some months ago, and the car still goes strong. I don´t apreciate any power gain with it, but it makes a little more whistling noise when accelerating.
Yeah, mine had more induction roar but less power, just wasn't performing like i would have expected.
 

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Drove around 30 miles and still flat as a fart, so hoyed the K&N out and refitted the OEM one and presto full powers back. Don't know whats going on but theres definitely something not quite right here. Even let the wife drive to see if she could notice the difference between the two and she felt as if the turbo had been nicked when the K&N
was fitted.


K&N panel filters are a load of
! Will not be wasting any more cash on them in the future.
As Stingy said, clean it and re-oil it. There's far too many people out there, myself included, please running these filters without issues.
 
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