Evans Waterless Coolant
The information here has been supplied by the Register’s Technical Adviser, Alex Eacock, who is a senior family member of EMC Motorsport.
This is a bit of a subjective matter, the product itself works well, we have tried it ourselves and it has lots of benefits. Because it is waterless, the coolant doesn't expand the same as water based types, so you get zero pressure in your cooling system. This has the benefit of being safer to work on when hot and putting less stress on the components in your cooling system, because it doesn't boil or cavitate like water you get less problems with air pockets and hot spots in the water jacket.
The downside to this is that to work properly, there has to be less than 1% water content in the coolant which involves lots of purging of the system with the correct cleaner, a very messy and time consuming process.
On the operational side of things, the engine gets up to operating temperature very quickly, unnervingly so actually. I think this was down to the more stable and conductive nature of the fluid (I was told by the engineer from Evans but I can't remember) allowing the heat to circulate and pass through the fluid easier and hence, faster.
The other part which I struggled with is that the engine runs hotter than its normal operating temperature on the Evans fluid. If you aren't a gauge watcher or have zero mechanical sympathy then you will probably be okay but I couldn't have the gauge running that high, it just isn't right!
For a 968 that has alloy bores, the difference between good and knackered engine is only a few degrees due to the tighter bore tolerances and for me it was running too close to critical the whole time.
We did however, actually run a customers 944S2 race car on Evans coolant for a season or two and he had no issues whatsoever, the gauge being higher didn't bother him and he was very happy with the product. The architecture of the S2 and 968 is virtually identical, so it is a good comparison.
As I said at the start of the article, the product is subjective, it works fine and does what it is supposed to. Me being a bit of a wuss meant that I couldn't relax with the gauge running high, so I don't run it.
The last point worth noting is that you cannot top up with anything other than Evans, so make sure you carry a litre or so with you everywhere!