While the late 1970s might not be widely regarded as the peak of General Motors, the 1977 Cadillac Coupe de Ville stands out as an exception. Unlike the Cadillac CTS-V, which delivers 640 horsepower, this impressive Coupe de Ville boasts a four-digit power output at the rear wheels, courtesy of a customized 6.0-liter LS V8 engine.
Owner Shawn Gilbert hasn’t detailed which specific LS engine powers his Cadillac, only indicating that it’s a “six-liter.” The prevailing speculation is that it’s an LS2, recognized as the most potent stock 6.0-liter LS engine produced by GM. The LS2 was utilized in the mid-2000s in vehicles such as the C6 Corvette, Pontiac GTO, Cadillac CTS-V, and performance trucks like the Chevy SSR and Trailblazer SS. Additionally, it served as a foundation for a NASCAR engine.
In its original form, the LS2 generated 400 horsepower and matched it with 400 lb-ft of torque. After undergoing extensive modifications—including a twin-turbo system designed by Big 3 Racing in Ohio, LSA cylinder heads, a Holley Dominator EFI setup, and enhanced internal components like pistons and rods—this engine now produces an astonishing 1,172 horsepower at the wheels, enabling this Cadillac to achieve a quarter-mile run in just 8.80 seconds at a speed of 152 mph. Interestingly, the engine block, crankshaft, valves, and rockers remain stock. The power is managed by a Turbo 400 automatic transmission, driving a 3.50 rear end.
So, how does it perform in everyday driving? “It still drives like a Cadillac, believe it or not,” claims Gilbert. The interior largely retains its original character, featuring plaid bench seats and ample wood accents. This remarkable build is prompting us to reconsider our views on the Malaise Era..