Earlier today I posted a blog entry suggesting that GM made a mistake showing the Volt. And now I’ve come across an instance where GM showed a promising concept three years ago, but has let someone else be the first to actually offer such a product.

The new case involves a sequential twin-turbo diesel good for over 100 horsepower per liter. Over at Autoblog I read that BMW is about to sell a new diesel that wrings 204 horsepower out of two liters of displacement.

My immediate response: wow, I had no idea it was possible to get so much power per liter out of a production diesel. Diesels are inherently low revving engines that produce a lot of torque at low rpm, but run out of steam rapidly as the revs increase. Since low-end power is what Americans tend to crave, I’ve thought that diesel engines are perfectly suited for them. So I find it quite ironic that they’re most popular in Europe, home of drivers that allegedly enjoy runs to the redline.

My next thought: has any other production diesel reached this mark, or is BMW’s new 2.0 the first?

A quick search found that GM introduced a 1.9-liter diesel three years ago that put out 212 horsepower, which works out to 112 per liter. The secret: the world’s first application of sequential twin turbos to a diesel.

The catch: that engine remained a concept. If you actually want to buy a diesel engine with a relatively broad torque curve and over 100 horsepower per liter, it looks like it’ll have to be from BMW, not GM.

GM needs to get its priorities in order. Getting new technology into production first is what counts, not the concept.