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Jason SB MK3 RS
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Something I read may be of interest :)

As air temperature increases, the density of the air, and the amount of oxygen it holds decreases. This means that the turbocharger has to work harder, spin faster and compress more air to produce the same amount of boost it would at lower temperatures, so makes sense to lower inlet air temps by a trying to prevent heat soak from the engine bay and getting a more efficient cool air flow to the filter housing.
The heat shield on the Ramair I recently fitted to the RS certainly keeps cool air flowing to the filter from the factory cold feed. However hot that engine gets the the heat shield is almost cold to touch. And the sound is superb from it :thumbsup:
 

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Tangerine Scream ST3 2013, with some stuff done.
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1,394 Posts
Ive now replaced the K&N with a genuine standard filter, as I was getting a little bit of an erratic idle, since dropping the stock paper filter in, the problem has gone away.
So if anyone wants one of these K&N filters, give me a shout.
 

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Premium Member
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778 Posts
Ive now replaced the K&N with a genuine standard filter, as I was getting a little bit of an erratic idle, since dropping the stock paper filter in, the problem has gone away.
So if anyone wants one of these K&N filters, give me a shout.
Could always do with a spare as I need to keep them clean, and mine is pretty bad. How much bud?? As you are not far, I could collect next weekend. 🙂

I promise not to bring the GTC 🤣🤣
 

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Premium Member
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Ive now replaced the K&N with a genuine standard filter, as I was getting a little bit of an erratic idle, since dropping the stock paper filter in, the problem has gone away.
So if anyone wants one of these K&N filters, give me a shout.
As a follow up to this and also following on from what I did. (Replace OEM Paper filter for K&N E-9289 but leave standard air box in place) I have also noticed a rare but noticeable erratic idle. If I sit in a fast food drive through as an example I did notice that say in 5 minutes of sat at idle speed (750rpm I believe) I noticed this happen on 2 or 3 occasions. Slightly frustrating as I am yet to receive / fit my RS air box.
 

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Nick - Mk3.5 FL ST3 Moondust Silver
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5,662 Posts
Discussion Starter · #31 ·
When I got my CP2v2 upgrade at Collins I also asked about the K&N or similar with them rather than fitting a paper filter & they advised against it as it could cause just that - erratic idle. Hence as much as I would like a K&N I have so far resisted the temptation!
 

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Premium Member
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When I got my CP2v2 upgrade at Collins I also asked about the K&N or similar with them rather than fitting a paper filter & they advised against it as it could cause just that - erratic idle. Hence as much as I would like a K&N I have so far resisted the temptation!
Hi are you running your CP2V2 on stock or have you made any other modifications
 

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Premium Member
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34 Posts
Having now fitted the RS Air Box the erratic idle has gone. Not really sure I can even explain why but maybe the larger flowing filter just needed that bit extra airflow into the box itself. I have been running this set up now (K&N E-9289 and RS Air box) for about 6 weeks and it’s been great.
 

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Premium Member
Nick - Mk3.5 FL ST3 Moondust Silver
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5,662 Posts
Discussion Starter · #34 ·
Hi are you running your CP2V2 on stock or have you made any other modifications
I have fitted an uprated intercooler as I got a rock through the OEM one. Everything is fine plus I seem to have got rid of the annoying hesitation that the map sometimes had at low throttle/boost applications!
 
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