For years now, the big three of German luxury cars->ke505 have been involved in a Cold War-style technology race that is not likely to abate any time in the near future. So when BMW->ke178 announced that it was debuting a new water injection system for the M4 GTS, one that should make it into production cars in just a few years, many people suspected that Audi->ke14 and/or Mercedes-Benz->ke187 wouldn't be too far behind in bringing out similar systems. But the latest word from Mercedes is that it isn't happening, and that the systems require a lot of effort and money for very little return.

This information comes by way of Dr. Thomas Weber, a board member in charge of development. He compared the systems to the old variable compression systems, which sounded impressive in theory but ended up being far more trouble and expense than they were worth. Weber did go on to say that water injection gets brought up at every powertrain conference, but that it never actually moves forward. But there are those at Mercedes who believe that water injection could work. Klaus Frohlich, another board member, is pushing for them, seeing them an excellent way to reduce emissions.

Continue reading for the full story.

Why it matters

At the moment, using water to cool cylinders is a useful technology, but not so much so that Mercedes can't afford to ignore it, especially given the extra layer of complexity and expense that it adds. But there is always the risk that it could evolve into something much more useful in the coming years and BMW would therefore have a strong head start. But this is the risk in pursuing any new technology: there is no way to know what will pay off and what will be a money pit of a dead end.

2015 BMW M4 MotoGP Safety Car

You can read our full review here.