Best intercooler for tte420 setup

a3 turbp

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had my S3 tuned by RTECH recently and Niki advised that my current milltek exhaust is restricting flow past 400 bhp so I’ve now ordered a full BCS system. Also whilst talking to Niki he mentioned for best results I’m best looking at removing my current airtec cooler and fitting a welly cooler. What’s other people’s views on this? Will I just be wasting more money doing this for not much difference?
 
If Niki has advised it, go with it, he doesn't recommend if it's not needed
 
If Niki has advised it, go with it, he doesn't recommend if it's not needed
I thought that too but didn’t know if I’d gain too much especially the amount of work involved in changing the cooler
 
The true eBay Welly cooler requires some butchering of bumper, etc... Does work well due to how the pipework is and cools properly too, so if you're chasing numbers then it's the option to go for.
When I was chatting to him at VAG Tuner live a few weeks ago, he showed me a cooler on their stand that seems to be a good option for OEM fitment, but can remember the name. I doubt it would be as good as Welly cooler though, due to where it sits.
I have an Airtec stg2 and really see no point in changing it, but then I'm not planning on going further. Still, peak 417bhp/396lbft isn't too bad for a car with a cat, which would be restricting things quite a bit.
 
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The true eBay Welly cooler requires some butchering of bumper, etc... Does work well due to how the pipework is and cools properly too, so if you're chasing numbers then it's the option to go for.
When I was chatting to him at VAG Tuner live a few weeks ago, he showed me a cooler on their stand that seems to be a good option for OEM fitment, but can remember the name. I doubt it would be as good as Welly cooler though, due to where it sits.
I have an Airtec stg2 and really see no point in changing it, but then I'm not planning on going further. Still, peak 417bhp/396lbft isn't too bad for a car with a cat, which would be restricting things quite a bit.
My car made 400 bhp and 400 ftlbs. Niki said it would be higher with a BCS exhaust that’s why I’ve ordered new one. Problem with my tte420 is that it’s an early one and suffers from compressor surge so if I do want more power then I’ll need to get it taken off and sent to Simon sharp to be rebuilt to new spec tte420. The only problem I find with the airtec is over these past few weeks with this hot weather I’ve felt my car suffering with heat and feels down on power. Today whilst driving around in the cooler temps it felt really quick again. How do you find the BCS exhaust? Is yours powervalve? I’ve ordered a non powervalve system the same that Justin has on his monster S3
 
The only problem I find with the airtec is over these past few weeks with this hot weather I’ve felt my car suffering with heat and feels down on power. Today whilst driving around in the cooler temps it felt really quick again. How do you find the BCS exhaust? Is yours powervalve? I’ve ordered a non powervalve system the same that Justin has on his monster S3

I think that with the hot weather the only people who found it not be an issue are running water meth haha

Yes, I have an older style PowerValve system. It originally had a 200 cell cat and now I run a decat. I've also clamped the valve slightly open as originally done by @smurfworth, so it's not as subtle as before, but still sounds lovely.
 
I think that with the hot weather the only people who found it not be an issue are running water meth haha

Yes, I have an older style PowerValve system. It originally had a 200 cell cat and now I run a decat. I've also clamped the valve slightly open as originally done by @smurfworth, so it's not as subtle as before, but still sounds lovely.
Niki told me he don’t like the powervalve system, he said you can feel the valve shutting then re opening on gear changes and actually lose performance so I’ve listened to his advice, I know what you mean with the meth though but I don’t really want a tank in my boot so I’m gonn leave that I think
 
Niki told me he don’t like the powervalve system, he said you can feel the valve shutting then re opening on gear changes and actually lose performance so I’ve listened to his advice, I know what you mean with the meth though but I don’t really want a tank in my boot so I’m gonn leave that I think

I share your view on meth - it's great for chasing numbers, or use on track/drag, but not ideal for a road car.

The valve does get in the way, but it's not extreme... Plus clamping it slightly open reduces the effect massively.
 
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Yeah I think I may just fit the new exhaust then get the turbo rebuilt and see how it is then. Like you say anything over 400hp in these cars is good so I’m happy
 
Mine was also mapped by Niki and made 421 and I have a full miltek decat exhaust. I run a Wagner intercooler. I’ve still got a meth kit to fit but I’ve had that over a year lol. I’m in too minds wether to change to a welly cooler instead and not fit the meth. Also are you still on stock internals as you don’t want to push them too far espicially if it’s not a cdl
 
I think this is about flow and not so much cooling so look and see what the max flow for your chosen cooler is before you buy. I went for the Wagner competition because its rated to 500bhp so if i go TT420 i am covered.