I just put a K&N induction kit on today, and I found it more involved than the website/instruction sheet make out.. Its certainly harder than filing up with petrol.
For a start, there's no reference to what you might do with the air box, which you discover is in the way as soon as you start. Plus, their cold air feed doesn't seem to be planned very well, and is not enclosed as one imagines it should be. Their suggestion points a cold air feed vaguely at the cone filter, but it's a tight fit in there, and it doesn't end up being very well protected. I wouldn't be too happy working under the bonnet in the rain for more than a few seconds.
What I ended up with:
Took off the top of the airbox, bit tight in places, and it *really* helps to take the brace off the top of the battery carrier, so that there is some give in the battery housing.
I also took out the offside light assembly and removed two screws from the wheel arch carpet to pull it back for access to the back.
I definitely couldn't have done it without these steps (not mentioned in terrible instruction sheet that comes in the box and is repeated with higher res pics in pdf on website).
Taking off the air box and letting the cone filter sit on top of it will do some people, but it really should be enclosed, and as soon as I find the bits, I'll do it too.
I attached it at a downward, inward angle to the front grille, and went under the support where the horn hangs.
I took out the air box lower part, which was a bit messy, and cut off what I suppose is used as a muck trap or is something to do with waste water, because there no components in it (its been referred to as the Soda Can, more mini-bar sized though)
Having cut it off, and drilled through the end of the flex-hose (shouldn't this be done before it ships?), I used 2 long cable ties linked together to tether it to the air box base like a nose bag.
I now have the air feed that comes in the wheel arch, and a new cold-air from the front grill to the base of the air box, which should give the filter at least 60% cold air.
I've seen pics on here of a fully-enclosed arrangement, which I was unable to get the bits for in either B&Q plumping section or Halfords.
The induction roar doesn't kick in as many have said until about 3000rpm, but I really like the sound it makes personally. A loudish hum rather than whine, does really encourage you to stay in 3rd longer than you should though!.
I made before and after videos at various speeds and gears, just putting it together now, I'll stick it up here for anyone who's considering the upgrade.
