B8 S4 - Heat Exchanger Upgrade Options


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Jun 21, 2017
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I plan on going stage 2 in the next few weeks but would also like to upgrade the lame factory heat exchanger at the same time. There are loads of kits available but for my cars spec the cost would be ridiculous.

I have ADS cooler, auxiliary water cooler and the small supercharger water cooler (see image below) so i would need to relocate/factor these parts into any upgrade which is a pain as all the kits are over £1300 with everything considered!


My question is, if i replace the current main heat exchanger (item 3) with a slightly larger item is it worth it and is there enough space to consider this an 'upgrade'. I'm thinking a twin pass would be better but is there anything available that would fit without relocating the ADS Cooler? My indy can fabricate a mount to attach it to the crash bar if required but im just wondering if this is even worth considering...
That’s the one I saw and liked the look of after researching, especially at that price.

Problem is, I don’t think it will fit without having to relocate the ADS cooler which I’d rather not do.

With only stage 2 power and not dual pulley I’m thinking that I don’t need massive cooling improvements. A slightly larger and more efficient exchanger would be ideal.

I wonder if the smaller version Merc offer would fit without needing to relocate anything else?

APR do what they call a fit kit to relocate it.Looks easy enough to put together,or around £50 to buy