Induction mouth

[WRXconvert]

has anyone had a look at the induction mouth just above the radiator on the right hand side? im very puzzled as to why VW has developed it the way they have... the air has to travel down and then get kinda sucked up. Anyone who has a bit of time have a little look at it... i bought the right kind of tech hex head allen keys just so i could rip it out and look at it. it deflects more air away from the intake to the airbox than to it. anyone got any ideas as to why they have done this? all i can think of is that its an extra measure to stop stones or debris entering the turbo. but thats what a good airfilter is for. i will price a new part from vw so that i have a spare... but im certainly looking at playing with this so allll of the air that gets vented to this mouth goes into the airbox. will require a dremel. i was looking at playing with the irbox itself and smoothing it out and making the inlet bigger, but the price for a replacement box from vw is $302 odd... anyone with any engineering knowledge have any thoughts on this?
oh btw, i took the air deflector off as said above and drove the car with the inlet pipe into the airbox just pointed in the general area of the grill.. and the car seemed to pickup quicker (and had a little bit more turbo noise) so i think im onto something.

[carazy]

They normally do this sort of stuff to either reduce induction noise or reduce the chance of water being sucked into the turbo.
If you modify it you will end up with a little more noise, a higher chance of sucking water into your turbo and normally no increase in power.

[Guy_H]

Its pretty easy to log the intake temps from Vag Com or ECU Explorer, we have seen considerable drops in intake temps from modifying the cold air feed. look for an update on the "Polo on roids" thread in a couple of weeks

[WRXconvert]

Cheers guy. the amount of air that is deflected down from the airbox feed is amazing i just can't understand it. Guy, im not going to run into any problems with A/F ratio or anything like that if i have a ram air feed style am i? i propose having all that air going into the feed. i feel kinda gipped that im losing so much of the air. anyone who is serious about doing further mods to their cars should have a good look at this feed... its a major restriction.

[Guy_H]

WRX, we tested blocking off the lower portion (the bit that sucks in the engine bay) - you should be fine - the layout of the airbox is very restrictive as well. Unfortunately we didnt have a car with just a chip for airbox testing (only the K04 car) - but the only time we ran out of Fuel was with the super high flowing BMC CDA.

We have some "motorsport" factory intake feeds that are 40% larger & have a cold only feed into the stock airbox in transit - will be nice to see how they work!

[Spec83]

Guy -I was just thinking of bolting up an Apexi power filter with an adaptor plate to the end of the stock hose and eliminating the air box altogether - just use a k&n oil filter for the cold start pump like you guys did on the BMC filter... No cold air could be a problem thou - thoughts??

Let me know when you get these motorsport intakes in - would be keen to try one out on a non-chipped polo...

[Guy_H]

Hey Spec, if you are going to try to run a pod style filter, you really need to have it shielded from the engine bay heat or you will go backwards. The BMC CDA is carbon so it shields it.

On the polo (and most of the new VW's) you cant run a tube under the battery & headlight down to the lower passengers grill as there is the electric power steer unit located there now!

[WRXconvert]

WRX, we tested blocking off the lower portion (the bit that sucks in the engine bay) - you should be fine - the layout of the airbox is very restrictive as well. Unfortunately we didnt have a car with just a chip for airbox testing (only the K04 car) - but the only time we ran out of Fuel was with the super high flowing BMC CDA.

We have some "motorsport" factory intake feeds that are 40% larger & have a cold only feed into the stock airbox in transit - will be nice to see how they work!

Motorsport? is that the brand? I have looked at a few different options as to how to modify the airbox. Unfortunately as you have previously stated guy, there is basically no position down low to feed an induction pipe to. i was honestly thinking of doing some R&D into it, but just by looking in the engine bay and all of the front bumper there is just no where to run a pipe to. The only thing i can think of is enlarging the inlet into the airbox by about 25-35% (buy means of PVC pipe or similar), using a suitable feed such as an equivalent to the pipercross pipe (its basically an aviation induction tube, i can get some through an RAAF'Y mate) and modifying the intake feed, by means of dremeling the deflector off, and adapting some sort of back plate which i can adapt the air feed tube to. hope this makes sense... i am blabbering a bit...

P.S got the APR 6 hour free trial.... and just popped in a pipercross panel replacement (which apparantly doesnt need oil) and its unbelievable. the induction noise IS louder.... but also spools up a little bit quicker too...

[shaneth]

Motorsport

[GTIJNR]

We have some "motorsport" factory intake feeds that are 40% larger & have a cold only feed into the stock airbox in transit - will be nice to see how they work!

That sound great Guy, can u throw up a pic or some info? thanx

[Guy_H]

Its a factory part - When they land, I'll post some pics!

[WRXconvert]

ok guys heres some pics of the ghetto operation, i have dremelled the air deflector off that was deflecting air away from the airbox intake. i feel as if it has made a slight increase in pickup and the turbo starts to spool a little quicker... also inlet temps must be a little lower, because now it is actually getting force fed some cold air. anyways heres some pics.

, ,

now what i want to do is make sure ALL the air that that mouth picks up goes to the airbox, to do that i am going to have to fiddle around with a few other things such as the airbox, and the intake tube, as well as the rear of the mouth. as you can see by the last picture there is still a little gap where the air can escape... and we dont want that... we want it all to go to the turbo... cos we are greedy little turbo junkies.

so the airbox is going to "smoothed out" and the inlet increased with a bell mouth pointing upwards toward the filter... as you can see the inlet isnt that big when stock.

[WRXconvert]

next i am going to find some suitable type venting... because this is too restrictive...



and last but not least, adapt something other that this back plate which will pickup all the air that the mouth picks up... im thinking PVC or something... not too sure yet...

[WRXconvert]

i am disconcerted as to the reason why so many people have looked at this but made no comments....

[Timbo]

Well, IMHO, there's really little power to be gained in either induction mouth/airbox mods, or exhaust mods apart from more noise. Which is fine, if that floats your boat. I'm happy to be proved wrong, but you have to post hard before-and-after evidence, and I've not seen it with other cars. My 2psi