BKinzey, Bkinzey, Bkinzey...
They are comparing the silhouette of the new diesel engine against a 6.2l small block gas engine that is currently in production. This new diesel engine isn't going to be competing with current diesel engines, it will be offered in smaller vehicles like mid-size SUV's according to the article.
“To really be able to have maximum flexibility in how we use this powertrain, it has to fit in the envelope of the gasoline small-block engine. It gives us a lot of flexibility to introduce this powertrain,”