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BORA owner!!!!!!
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Hi Guys and gals, yesterday i was a bit bored and so thought i better fit my audi tt wheel arch vent, its purpose is to allow the air passing the through the intercooler to escape , as in the original design the air has no where to go once it has passed through it,maybe causing heatsoak, so if the audi tt has a vent, then i cant see any problem fitting one to my golfy, anyway first get a wheel arch from a audi tt part number: 8N0821172B, for the incosiderable amount of ?17 + vat, or get a second hand one for much cheaper, then cut out the vent leaving 3/4" of plastic all the way around the edge, then dremel the sharp/little pieces that are sticking out from the sides that you have cut, and you should be left with one wheel vent, when taking you old wheel vent arch liner off just check where roughly the intercooler is and mark the top of the intercooler on the wheel arch with a pencil or masking tape, then put the vent on top of your wheel arch, noting the top of the intercooler, and using a pencil make a line around the vent, then cut out the marked area, i used a sharp stanley knife, and it cutted the arch liner easily, deburr the edges, and check that the vent fits, adjust the cutout so that you get a snug fit, i then drilled 8 x 5mm holes around the vent and in the wheel arch liner ,

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then i used speed nuts on the wheel arch liner, and attached the vent to the liner,

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looking good allready, then because i,m `anal`, i then used masking tape around the perimeter of the wheel arch vent leaving a 4-5 mm gap around it,

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so that i could then use black mastic to seal the vent in , and to try and make it look factory,

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i left it for a day to dry , then fitted it back ,

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after road testing i found that i had wheel spin in every gear!!!!!,

Well not quite!!, but i,m sure it helps with cooling the intake air temp, now i need to do Garys smoothed airbox mod , then that,ll be the inlet air side done!!!.
 

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BORA owner!!!!!!
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Discussion Starter · #3 ·
OOOOOOHHHHHHHH NOOOOOOOOOOO!!!!, has anyone got a piccy of the wheel arch vent off an S3?.[:O]
 

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Hey don't panic. I did this mod some time ago and I think it makes a difference even though I don't have data to back that up. Than I noticed that after parking the car there is a big build up of heat under the wing because heat rises and there is no where for it to go unless you put vents in the wing itself. So I put a second TT vent right above the first one to provide some ventilation to the top of under-wing space. Must be doing something because I can now feel warm air coming out when I park the car. Tried a few experiments with a small 12 V fan there to help the ventilation when stationery. Setup was a far from optimal but the fan does reduce the temperature of the wing by a couple of degrees. Have not done any comparisons of vent and no vent.

To summarise, if you want better cooling under there, go for a taller vent rather than a wider one.
 

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Discussion Starter · #10 ·
I,ll get the S3 vent when i have the r-line bumper fitted next year, better start looking through the breakers for the vent.
 

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You dont actually need to buy the TT or S3 vent kit, just cut strips in your current vent and bend them to protect from splash.
 

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Quote: posted by Mister_E on 01/11/2004 09:52:00

Is either the S3 or TT arch liner a direct replacement for the Golf one??

Nope
 

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Interesting [??]

I guess its a worthwhile mod to any car which has an intercooler, the extra vents allow the air to flow right through the car, thus more cold air entering & alot more hot air exiting...

Which side is the intercooler on a PD150 anybody ???
 

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PD150 is a front mount IC aint it? Plus i dont think its that much worth while doing on a TDI as they dont suffer from heatsoak.
 

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Quote: posted by MikeTDI on 01/11/2004 11:41:00

PD150 is a front mount IC aint it? Plus i dont think its that much worth while doing on a TDI as they dont suffer from heatsoak.

Why not? I thought all turbo cars suffered to some extent - I know petrol turbos suffer more 'cos of the higher engine revs/temp, but diesel turbos spin just as fast don't they.....
 

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Quote: posted by MikeTDI on 01/11/2004 11:41:00

PD150 is a front mount IC aint it? Plus i dont think its that much worth while doing on a TDI as they don't suffer from heatsoak but do suffer from heatsmoke.

LOL coudn't resist
 

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TDi's don't suffer from a lot of heatsoak because the fuel burning process is more efficient and therefore generates less heat. It would take a lot of abuse and a hot day to make a noticeable effect I think.
 

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Quote: posted by NikB on 02/11/2004 12:23:18

TDi's don't suffer from a lot of heatsoak because the fuel burning process is more efficient and therefore generates less heat. It would take a lot of abuse and a hot day to make a noticeable effect I think.

I'm not trying to be argumentative, I'd just like to understand...! so at the risk of sounding stupid....

Why does the combustion process matter to an intercooler? it is there to lower the charge temperature going into the engine, so by that any mod to lower the actual temperature of the intercooler (in this case by increasing the air flow) would be a 'good thing', wouldn't it?

Diesels are compression ignition and generate massive amounts of heat in the combustion process, hence why the engines are so much heavier, everything has to be so very strong.

I do realise there's a difference in engine temperatures between petrol and diesel, but heatsoak by definition is: heat coming from the turbo, engine etc and literally 'soaking' the intercooler, thus not cooling the intake charge as efficiently as it should. By it's nature there is less heatsoak when a vehicle is moving simply from the action of cooler air entering the engine compartment, so the real effect of heatsoak is only felt when in hot environments or stationary.

Is it that you're thinking of the FMIC on the 150, 'cos that's simply bigger than the side mounted intercooler, it would suffer from heatsoak too as it's infront of the radiator. The true benefit of the FMIC is that it's both bigger and directly in the airflow, not hidden in a wheel arch inside ducting (which is dead end 'cos it doesn't have the vent).

Guys, am I barking up a different tree here? (Or just barking[;)])
 
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