K&N advice & issues

polo-sib · Post by **polo-sib** » Mon Apr 21, 2008 12:34 am

Bought my K&N kit here:
http://www.knfilters.com/search/product ... =57-0193-1

Basically the K&N filter cone sits on the throttle body and that huge pipe is a cold air feed that you feed from the front and then cable tie down to directly blow onto the cone sitting on the throttle.

I heard that this is not an ideal location for the filter to sit due to heat and that the old kits had an additional pipe which is no longer in the modern kits, such as this one:

What I want to do is make a custom pipe, I had abit of trouble looking around for engine hosing as we are talking of a 50mm throttle body, so what I was wondering are any cheaper alternative or plain alternatives? I was thinking of using PVC based or similar piping from B&Q with the 50mm width to channel the K&N away from sitting on the throttle?

Secondly the cold air pipe is 60mm wide, should I get a bigger one and where is an ideal location for it on a 8v bumper?

Thirdly on the original filter box you have 5 pipes:
One heading to throttle (big)
One from the breather (medium)
One oxygen hose (small)
One vacuum hose (small)
One coming from the coal filter not sure what it's called (big)

When making the custom pipe should I attatch the:
Oxygen Hose? And/Or
Vacuum Hose? And/Or
The coal filter hose?
Back to the throttle body as I noticed the K&N completely ignores these?

Fourthly how hot does the throttle body get?

Many thanks in advance!

NOZ · Post by **NOZ** » Mon Apr 21, 2008 1:33 pm

I also attached the filter direct on the throttle and used the cold air feed, which I put through the plastic besides the radiator. Was gonna put a metal heat-shield in between the filter and engine but never got around to it.

I would've thought the breather pipe fits underneath the filter like my old 8v? You could attach a breather filter on the end so the gases just escape and don't return to your engine.

b-random · Post by **b-random** » Mon Apr 21, 2008 3:24 pm

What is the benefits of fitting a new air filter to the STD 8v Engine?

polo-sib · Post by **polo-sib** » Mon Apr 21, 2008 3:31 pm

b-random wrote:What is the benefits of fitting a new air filter to the STD 8v Engine?

Nicer noise, slightly more BHP if set up correctly with a cold air feed.

polo-sib · Post by **polo-sib** » Mon Apr 21, 2008 3:49 pm

NOZ wrote:I also attached the filter direct on the throttle and used the cold air feed, which I put through the plastic besides the radiator. Was gonna put a metal heat-shield in between the filter and engine but never got around to it.

I would've thought the breather pipe fits underneath the filter like my old 8v? You could attach a breather filter on the end so the gases just escape and don't return to your engine.

Yea the breather pipe does fit in under, but the three other pipes dont:
Oxygen Hose (small)
Vacuum Hose (small
The big pip coming from charcoal filter (big)

I'm just curious if linking them up to a custom made pipe would serve any advantage if they where linked up?

And do you know how hot the actual throttle body gets and around it? I imagine it can't that hot as most of the heat energy is taken away by the cooling system and the rest is radiated onto the throttle so the K&N and the custom pipe I'm planning to make shouldn't get that hot or am I wrong? As this will help me decide on what material I can use to make the additional ducting.

b-random · Post by **b-random** » Mon Apr 21, 2008 4:11 pm

polo-sib wrote:
b-random wrote:What is the benefits of fitting a new air filter to the STD 8v Engine?
Nicer noise, slightly more BHP if set up correctly with a cold air feed.

You'll need to be getting a fair of a lot more BHP to notice the difference in increase. especially on a 1.4

NOZ · Post by **NOZ** » Mon Apr 21, 2008 11:34 pm

The benefits ain't really much in terms of power from just an induction kit attachment. Its just there for your car to breathe easier. Other mods would benefit getting air easier by the induction kit if you get my drift.

Think the throttle body gets slightly hot by the engine heat that goes onto the metal. You could just touch the metal after a drive to see! I'm not sure about the other pipes either, don't remember what I did with them!

polo-sib · Post by **polo-sib** » Tue Apr 22, 2008 12:58 pm

NOZ wrote:The benefits ain't really much in terms of power from just an induction kit attachment. Its just there for your car to breathe easier. Other mods would benefit getting air easier by the induction kit if you get my drift.

Think the throttle body gets slightly hot by the engine heat that goes onto the metal. You could just touch the metal after a drive to see! I'm not sure about the other pipes either, don't remember what I did with them!

If you remember what you did with the extra pipes/tubes let me know, I'd imagine it gets hot but not to extremes, I've seen PP black plastic piping in B&Q and they can take up to 180c (a lot cheaper than the blue hose stuff you can buy). Can you get me a rough heat temperature of the throttle? If you don't mind as my car is in the repair center not sure when I'll get it back but as soon as I do I got a lot of things I want to do.

NOZ · Post by **NOZ** » Wed Apr 23, 2008 10:13 am

The B&Q stuff should be adequate mate but I doubt you should be worried if they've originally been fitted to a plastic airfilter box anyway.

The throttle body certainly doesn't get to 180c or I would've been in A&E the amount of times i've touched it! I'll see what I can do, mines in the garage but should be getting it back soon.