The car you see here is not a GNX. Hell, it's not even a Buick. You'd be forgiven if you thought it was, though, and it does sport a turbocharger underhood. David Morad was so enamored with the 6.6L LB7 Duramax diesel in his truck that he wanted to put it into something lighter and more fun. He decided to build a Grand National around the engine, and started buying up whatever applicable Buick body parts he could find -- right down to legit GNX dash plates. Next, he bought an '82 Buick Regal diesel that was to be the subject of the transformation. Unfortunately, that car literally self-immolated as he drove it home, sending Morad straight back to square one.

He subsequently found and bought an '81 Olds diesel and got to work. The car was cut in half so that a Regal rear end could be welded on, and then a laundry list of major modifications followed. To retain the stock Buick exterior appearance while incorporating the new powertrain, everything under the skin is is either extensively modified or custom fabricated in order to allow for the deception. Sure, it looks like a GNX, but this is really a scratch-built machine. Wilwood brakes lurk behind some absolutely wicked deep-dish Budnik wheels (dig those steamrollers in back), which nicely compliment the menacing black bodywork. Diesel Power magazine covers all the build's specifics in detail, and it's well worth a read.

If you're gonna masquerade as a GNX, you'd better bring some punch to the costume party, and Morad's car does. As of Diesel Power's publication, it ran an 8.25-second eighth of a mile, which they figure works out to somewhere in the 12s for the quarter. He'll be gunning for the 11s next, and additional performance upgrades are in store. Best of all? This is Morad's daily driver! He reports that it gets around 28 mpg in regular use and in the mid-30s on the highway. Not a bad combination: the looks of a GNX, the grunt of a big turbodiesel, and the fuel economy of cars that are a lot more boring. This thing had to cost a fortune to make, but Morad's clearly getting his money's worth on the fun scale.

[Source: Diesel Power via Next Autos]