This Craigslist-find, 800-hp Buick V-6 haunts us

With its twin intercooler scoops perked up like a wildcat’s ears, this Buick V-6 looks poised to produce some serious horsepower—and thanks to the madman known as Kenny Duttweiler, it lives up to that first impression. Local Craigslist trawling dredged up this nugget, an all-aluminum Buick 3.8-liter V-6 that pumps out nearly 800 hp at full tilt.

Who gets credit for this wild creation? Duttweiler Performance and TA Performance, each legends in their respective fields for building some of the most wicked powerplants on earth. While Duttweiler tunes engines and designs and builds motors, TA Performance has focused on Buick performance and originally commissioned these engine’s aluminum block and heads. The two worked together to build these units to serve sand buggies, due to the engines’ relatively light weight.

TA Performance brought its custom aluminum engine blocks and cylinder heads based on the infamous Grand National/T-Type unit, with several refinements to the oiling system and casting structure to improve the block’s power-handling capability. These were never found in production, but are instead poured out of a foundry in California not too far from Duttweiler’s own shop.

With a bore and stroke of 3.940 x 3.625 inches, these units displace 4.3 liters thanks to the Crower billet crank and CP pistons. The valvetrain starts off with a unique camshaft profile that combines the roller-lifter lobe profile of the later-model Buick 3.8 with the odd-fire ignition order in order to eliminate the weaker split-pin crank that was used in later Buick 3.8 mills.

This foundation worked around the factory limitations of the original iron block and provided a massive weight advantage over the common V-8s of the era, too, with Hot Rod citing that the package weighed under 300 pounds—nearly half of what a standard small-block Chevy weighs.

The seller states that this twin-turbo wonder is currently without a home because he wants to swap a naturally aspirated, stroked LS2 combo into his dune buggy—a choice that’s hard to argue. The LS is cheap and easy to work with, especially when most the most common repair components are sitting on the shelf of any parts house.

This unique slice of Buick hot rodding, however, looks ready to eat puppies and spit fire. (It probably already has, on more than one occasion.) Having sat in the tail of a Funco dune buggy for most of its life, the engine comes ready with an adapter for a rear-engine Albins five-speed transaxle. Even if you dumped your Baja 1000 ambitions and threw this back into a Buick, who could complain about an 800 hp V-6 under the hood of their blacked-out GN? Hell, it’s already packaged for a rear-engine setup—why not a 911 or air-cooled VW?

The seller is asking $18,000 and the listing can be found here.