K&N

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Bux657
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K&N

Post by Bux657 »

Does anybody know what different installing a box K&N on a mk3 2.8i will make?

I’m guessing not enough to notice.....
Mc Tool
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Re: K&N

Post by Mc Tool »

Well I dunno for sure that you will feel the difference in power but they are still a real good filter system if maintained so in terms of protecting your motor from dust ingress probly cant beat it ,and apart from cleaner and re-oiling oil its a one time purchase and will eventually pay for itself. Oh, and you get a sticker for the side window :xd:
You can use any old cheap degreaser to clean the filter ( get the water soluable stuff and rinse under the tap ) if using k&n oil but there are excellent water soluable filter oils available ,so you just run it under the tap. I like this way coz you can clean the filter with a continual flow of clean water rather than squeezing it about in a bowl of increasingly dirty and expensive solvent. :D just for the record I hate them poxy ramflow filters as the foam shrinks and air gets past between the filter base and the foam , however most dirt bike shops or flea bay can supply a piece of quality filter foam that can be cut to size. ;)
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Bux657
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Re: K&N

Post by Bux657 »

I’ve brought it now so will keep me busy tinkering under my hood for 5 mins anyways! My m8 said to drill the box but I don’t think I’ll bother with bodging about a classic!
Thank for your help👍🏻
Mc Tool
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Re: K&N

Post by Mc Tool »

My policy on modifying classic parts , if you have to , is to get another one 1st and then butcher the worse of the two .
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andyd
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Re: K&N

Post by andyd »

Bux657 wrote: Mon Jul 13, 2020 9:24 pm I’ve brought it now so will keep me busy tinkering under my hood for 5 mins anyways! My m8 said to drill the box but I don’t think I’ll bother with bodging about a classic!
Thank for your help👍🏻
I put one in my 2.8 as soon as i got it. Panel filters never going to give much increase in power, just means you don't have to replace it every service or so.

There are some threads on here about drilling airbox and/or removing the air intake pipe completely. Will make a nice sound but again probably won't increase power much at all. Did my XR3i years ago purely for the noise :D As you say a pity to damage something so old now!
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Bug
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Re: K&N

Post by Bug »

Bux657 wrote: Mon Jul 13, 2020 9:24 pm I’ve brought it now so will keep me busy tinkering under my hood for 5 mins anyways! My m8 said to drill the box but I don’t think I’ll bother with bodging about a classic!
Thank for your help👍🏻

No no no!
It's an old wives tale, passed on by numpties sat on bar stools.
You've just fitted a K&N filter to improve breathing, and now you want to change the intake system so it collects warm air from the engine bay instead of nice cold, dense air from out front?

Can you tell, I'm not a fan ;)
Mr B
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Re: K&N

Post by Mr B »

Bug wrote: Tue Jul 14, 2020 2:11 pm
Bux657 wrote: Mon Jul 13, 2020 9:24 pm I’ve brought it now so will keep me busy tinkering under my hood for 5 mins anyways! My m8 said to drill the box but I don’t think I’ll bother with bodging about a classic!
Thank for your help👍🏻

No no no!
It's an old wives tale, passed on by numpties sat on bar stools.
You've just fitted a K&N filter to improve breathing, and now you want to change the intake system so it collects warm air from the engine bay instead of nice cold, dense air from out front?

Can you tell, I'm not a fan ;)
You make a good point Bug, my car's always seem to have a little more power when the temperature is nice and cold, I think I read somewhere that it was to do with the air being denser and more oxygen which allows a better mixture with the petrol or something like that, someone can probably explain it better!

Wayne
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Paul G
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Re: K&N

Post by Paul G »

Spot on Mr B, colder air is denser and contains more oxygen hence bigger bang. The problem with just having a K&N or similar sitting on the top of the carb can come with winter where they can cause carburettor icing. Manufacturers do not put warm air intakes on for no reason!
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Bug
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Re: K&N

Post by Bug »

Paul G wrote: Tue Jul 14, 2020 3:33 pm Spot on Mr B, colder air is denser and contains more oxygen hence bigger bang. The problem with just having a K&N or similar sitting on the top of the carb can come with winter where they can cause carburettor icing. Manufacturers do not put warm air intakes on for no reason!
Not such a problem with the 2.8i where it's tucked away in its nice little box.
The theory with denser air isn't just more oxygen though. It's because to keep the correct ideal mixture of approximately 14:1 (air to fuel ratio) you therefore have to add more fuel. As the fuel is effectively the store of energy that needs to be released, the more fuel, the more energy to force that piston back down.
I have on occasion noticed better performance in the winter, allied to a slightly greater fuel consumption.
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Re: K&N

Post by Mc Tool »

I reckon the extra fuel consumption was just you enjoying the extra power :D . I been thinkin maybe denser air would artificially raise the compression ratio a tad and at the same time , being cooler reduce the liklyhood of detonation . Diesels do it too. The difference between a hot day and a crisp dawn decided wether I towed my boat over the spooners hill in 2nd or 3rd gear.
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Bux657
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Re: K&N

Post by Bux657 »

Either way, not going to drill the box, fitted the K&N, not sure weather it’s improved performance, car sounds awesome as standard, drives like an analogue coffin rocket anyways and I’m used to my crap drum brakes! 😂

Fucking love it!
Mc Tool
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Re: K&N

Post by Mc Tool »

I once got told by a diy racer that if unsure about a mods benefit power wise ,give yourself time to get used to it and then reverse it (if possible ) the theory being that you will notice a small drop in power easier than a small increase, so maybe putting the old air cleaner on for a lap could comfirm or deny wether the K&N is better. :)
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andyd
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Re: K&N

Post by andyd »

Bux657 wrote: Wed Jul 15, 2020 9:07 pm Either way, not going to drill the box, fitted the K&N, not sure weather it’s improved performance, car sounds awesome as standard, drives like an analogue coffin rocket anyways and I’m used to my crap drum brakes! 😂

Fucking love it!
Changing the standard exhaust system and manifolds/kidney boxes to a sportier system does help performance a little and sounds even better :D
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