K&N's don't work - It's Official!

[takethefifth]

Well mine doesn't anyway! 

I had to remove my 57i induction kit last weekend as one of the mounting brackets decided to fall off. I thought i would give it a week to get an idea of the difference.

Replaced it with the standard airbox (no drilling, trumpet intact) and a bog standard MANN airfilter and the car is definately faster! Noticably so!

It doesn't sound as raucous, if anything it sounds like the engine is being restricted a little but.... its quicker! No question.

This thread was really just to say, yep i've tried it and what everyone says is right, standard airbox is best, the germans knew what they were doing! If only i'd listened to people sooner...... 

This is on a standard 8v Digi GTI with a Milltek exhaust. Results may differ on other cars....

[Mk1Mad J - 16v]

  57i's or any "induction kit" are a total waste of time - get yourself a K&N panel for your standard box and forget about air filters for life 

[jaybv6]

57i's or any "induction kit" are a total waste of time - get yourself a K&N panel for your standard box and forget about air filters for life 

Induction kits do the trick and when they don't work properly it usually down to them not being fitted correctly.  I don't just mean fitted with a disregard for the instructions but if you fit them with the supplied "Cold air Feed" it's not going to work as well as it should if you used a bit of ingenuity.

I've used K&N induction kits on my last 3 cars (Cavalier GSi with 180bhp, Calibra V6 with 194bhp and my current Vectra V6 with 195bhp) and they've all helped in the horsepower stakes and thottle response.  So what's the difference when I fit them?  Well the standard cold air feed is junked and I build my own enclosure for the induction kit (much like the Viper induction kits).  The enclosure is treated to heat wrap and if I feel flush carbon fibre to finish it off.  The enclosure then has a dedicated cold air feed from the front of the car, the more direct the better, and is attached to the sealed enclosure.  The results are outstanding, especially on the V6.  Below are a few pics of the inbetween stages of my Calibra V6.

Here's one of the Towing Eye converted to a functional NACA Duct and also how I made it.





And the tin that I used as the enclosure (before it got finished and sealed off.

[Mk1Mad J - 16v]

How well does that work when its freezing cold and the air box would normally be taking its feed off the exhaust manifold?

[Neaty]

i have only ever had one on my 8v, which was already there. I just liked the noise tbh   

i like the inginuity there jaybv6.

[...joe]

yeah good ingenuity but the simple fact is no-one realy fits them like that and what you've made is an enclosed induction kit with a cold air feed......... much like a standard airbox with a decent panel filter! viper kits etc do work but as a general rule, bolt on induction kits do sweet fanny adams!

[mk2mark]

Yeah, airboxes are not just restrictive to dampen sound, like what has been said an upgraded standard filter will still take advantage of the standard airbox's resonating properties etc.

[jaybv6]

How well does that work when its freezing cold and the air box would normally be taking its feed off the exhaust manifold?

Which cars are set up to take hot air from the exhaust manifold.  No car I've owned  ever has unless the Golf is different.  Even if the weather is freezing the induction temps being low is a good thing as the charge will be alot denser.

And yes, out of the box they certainly don't always work as people expect  but with a bit of creativity and less than £20 you can build your own enclosure.  Me, I used a Nescafe Coffee tin  .

[Neaty]

this reminds me I need to get a new airbox for my valver, I put too many holes in mine! 

[keithyboy]

They work on 2.0 DOHC Sierras.