Cold Air feed to Standard Box

[Woodyman84 3]

Ok i ran a cold air feed to standard boxes with a k&n panel filter in the past (MK2 GTI) an had some fair results in terms of throttle response.

Ive had a poke around and i see the original feed goes into the wing.on a mk3 VR

Dont much fancy running a pipe down inside engine bay either.

So my question is, if i take off the Wheel arch inner trim can i get my feed down to the lower grill.

any tips greatly appreciated.

PS (when i do it ill try get some piccies and do a guide as its a nice budget mod)

[mattvr6 133]

Fairly sure u can get a feed down there,my wing is off at the min so ill hav look pal

[russj249 2]

You'd be best moving the charcoal canister and run it down that gap.. I ran my setup like that for a bit so will dig out a pic...

[russj249 2]

That is through the hole that is exposed when the charcoal/carbon cannister is removed.. would be dead easy to run some flexible pipe to the inlet of the standard air box, and easily adapt the drivers side lower grill to take the feed.

[Woodyman84 3]

Great replies guys thankyou very much!!

Dumb Question but what is that carbon cannister for? i noticed it when i had a poke about the other day

Ignore the dumb question i notice there are a million old threads on it.

And extra DIY to add to my list

[russj249 2]

Pretty simple to remove too . Just a case of a couple of pipes being cut ans linked up..

As for its job.. in short, it takes the vapours from the petrol tank, and with a little purge valve that connects to it, vents the vapours through the charcoal filter inside and into the inlet manifold to be burnt with nornal combustion.

[Lukey. 381]

if you do this you have to seal the end of the vac pipe that goes to the inlet

[russj249 2]

if you do this you have to seal the end of the vac pipe that goes to the inlet

Only if you're venting the purge valve to atmosphere.. if you connect the pipes back up its just the same as standard just without the canister in, that's how I ran mine and it worked fine.

[Woodyman84 3]

So u can either connect the 2 pipes together directly. Or block off the black vac pipe an vent clear pipe to wing? That right?

[Woodyman84 3]

So u can either connect the 2 pipes together directly. Or block off the black vac pipe an vent clear pipe to wing? That right?

[russj249 2]

Basically yea.. as long as you keep the valve in you're ok.. but if you vent to atmosphere you have to unplug the purge valve or it'll run a bit dodgy..

I did this with mine and kept having a random fueling issue when Stealth Racing were setting up the ECU for my turbo, the problem turned out to be I was venting the vapour to atmosphere with the purge valve plugged in, and apparently when the valve is operated, the ECU does something with the fueling, so was messing the fueling about.

[DrRich 1]

The ECU expects some fuel in the vapour and under some driving conditions lets this into the manifold as part of the total fuel the engine needs, so if the canister is gone, there's no way to be sure how much fuel vapour is being added, which throws the mixture a little. STFT should accommodate this but it may have a small effect on LTFT.

All in all, probably not worth stressing about too much - I ran mine like that when I installed the BMC CDA, and just plugged the pipe to the engine to stop a vac leak. The pipe from the tank should be open to allow venting of pressure due to temperature changes in the tank.

It means unburned hydrocarbons will enter the environment but is not measurable at MOT.