Watch: VW’s Water-Cooled Exhaust Explained

For a company that went all-in on air cooling early on, Volkswagen has taken to water cooling with gusto.

The company’s latest trick, available on the new Golf Alltrack, is integrating the exhaust manifold into the engine block. That allows the cooling system to work on the exhaust gasses before they go into the turbocharger.

Engineering Explained’s Jason Fenske, in the above video, goes through the advantages and disadvantages of this system and may not come as a surprise to you that the host of “Engineering Explained” is pretty excited about this new engineering development.

To be fair, though, it is pretty neat. With the exhaust manifold contained in the engine block, Fenske explains that the third gen 1.8-liter EA888 engine benefits from faster warm ups, which leads to less engine wear; a cooler catalytic converter, which leads to a leaner air/fuel ratio, which in turn leads to better fuel economy (up to 20% better on the highway according to VW), and more.

The new tech does mean that tunability is affected, though the aftermarket has always kind of been about finding workarounds, so that’s nothing new. The cooling load on the engine is greater and, of course, if there’s a problem with the manifold, it would likely be harder to fix.

Nothing’s perfect, but it is still fun to see how engineers are still coming up with creative ways to squeeze more and more out of every drop of fuel.