Hi guys. I've got a tuned vrs diesel running a k&n induction kit. It didn't have a cold air feed in any way so I added one and it did make a difference but my question is, what are the dimensions of the pipe leading to the throttle intake? I want to add either a flexible or hard pipe to the throttle body end and the other end, attach the air filter and mount it low down in the bumper. Any help would b great.

it did make a difference...

 

No it didn't because diesels don't work like petrols, the only difference it makes is your air is very poorly filtered and your turbo will be damaged.

fitted a pipercross on mine and its more responsive pulls better up the top end of the revs imo

fitted a pipercross on mine and its more responsive pulls better up the top end of the revs imo

 

How can fitting a different filter make your turbo boost higher and where is the extra fuel coming from?

How can fitting a different filter make your turbo boost higher and where is the extra fuel coming from?

didn't say it boosts higher that's the set through the map I said its more responsive and seems to pull better

didn't say it boosts higher that's the set through the map I said its more responsive and seems to pull better

 

Now think about what you just said.

 

You're hearing induction noise from the filter, but how does that change the performance of the engine if it's making no more torque or power?

Pointless on a tdi.... Does nothing

Pointless on a tdi.... Does nothing

Depends on turbo set up and power, airbox was deffo a restriction on mine

Depends on turbo set up and power, airbox was deffo a restriction on mine

 

If you're over ~220 BHP then yes Kev, the airbox can become restrictive, we know this, the OP has a mapped standard VRS.

 

Cold air feed is one of the N/A petrol tricks which doesn't work on turbos due to the heat soak from compressing the air and then intercooling it. If it really worked you'd have to remap to get any advantage at all because diesels don't self-tune like wideband Lambda equipped petrol engines do.

 

There's no advantage to using an aftermarket filter at all since their filtration is so poor, better to fit a larger standard airbox with a larger standard paper element from a more powerful car.

What he said....

If you're over ~220 BHP then yes Kev, the airbox can become restrictive, we know this, the OP has a mapped standard VRS.

 

Cold air feed is one of the N/A petrol tricks which doesn't work on turbos due to the heat soak from compressing the air and then intercooling it. If it really worked you'd have to remap to get any advantage at all because diesels don't self-tune like wideband Lambda equipped petrol engines do.

 

There's no advantage to using an aftermarket filter at all since their filtration is so poor, better to fit a larger standard airbox with a larger standard paper element from a more powerful car.

Have to agree but in many of today's thinking bigger more noise etc make the car faster,but some more knowledgeable know this is not always the fact,but with some its more of the placebo effect .

Thanks guys. The problem is that it came with a k&n with no intake pipe and no airbox. So until I get a standard airbox I'd rather have a cold air feed to it to prevent heat intake. It seems like a longer intake pipe, for now at least, is gonna work out cheaper than a second hand airbox. Holding value, if you can even get one. Thank you for your responses.

Have to agree but in many of today's thinking bigger more noise etc make the car faster,but some more knowledgeable know this is not always the fact,but with some its more of the placebo effect .

Absolutely mate. It's all in the head. Of course we all know opening up breathing on a car will help a little but can sometimes have a negative effect. The adverts 'can give up to 12bhp extra' give some folks the impression that you will feel a massive difference when in reality 2bhp is even advantageous. The problem is that my car was mapped with this induction kit so the engine is used to it. I'm not entirely sure how the engine will react to having less airflow on this map.

Have to agree but in many of today's thinking bigger more noise etc make the car faster,but some more knowledgeable know this is not always the fact,but with some its more of the placebo effect .

Absolutely mate. It's all in the head. Of course we all know opening up breathing on a car will help a little but can sometimes have a negative effect. The adverts 'can give up to 12bhp extra' give some folks the impression that you will feel a massive difference when in reality 2bhp is even advantageous. The problem is that my car was mapped with this induction kit so the engine is used to it. I'm not entirely sure how the engine will react to having less airflow on this map.

This was the vid that convinced me it was pointless

http://m.youtube.com/watch?v=gCi2yo4UqPI

There is vrs airbox in for sale section.

Now think about what you just said.

 

You're hearing induction noise from the filter, but how does that change the performance of the engine if it's making no more torque or power?

no not really u can hear it a little I said its more responsive might not have anymore power but def drives better!

Depends on turbo set up and power, airbox was deffo a restriction on mine

i'll be around 280bhp in few weeks

No it didn't because diesels don't work like petrols, the only difference it makes is your air is very poorly filtered and your turbo will be damaged.

What I meant was it made a difference in noise ie chatter, induction noise etc. I'm aware that diesels respond differently to mods that petrol does.

Struggling to work out where the throttle body is on a diesel vrs....

Anybody else?

If you mean the pipe from the stock airbox to the turbo (TIP - turbo intake pipe) its 76mm diameter iirc

Aye thts what I meant haha sorry. Been working on N/A cars for too long haha. That'll do nicely. After all the posts, someone gave me an answer to what I needed. Thanks buddy.