1978. The turbo 3.8 received sequential fuel injection and a wasted spark Distributorless Ignition System in 1984. In 1986 an air-to-air Garrett intercooler was added and the RPO Code became LC2. The LC2 engine has a bore x stroke of . The horsepower ratings for 1986 & 1987 were , respectively. The limited production GNX benefitted from additional factory modifications such as a ceramic turbocharger, more efficient Garrett intercooler, low restriction exhaust system and revised programming which resulted in a factory rating. The turbo 3.8 liter was used in the following vehicles: 1978–1987 Buick Regal Sport Coupe, T-Type, Grand National, and GNX 1978–1980 Buick LeSabre Sport Coupe 1979–1980 Buick Century Turbo Coupe & Sedan 1979–1985 Buick Riviera S-Type, T-Type and less than 100 Convertibles 1980–1981 Chevrolet Monte Carlo Turbo 1989 Pontiac Trans Am Turbo 20th Anniversary Edition The turbocharged 1987 Buick Regal Grand National GNX was called America's quickest automobile, and the model continues to be collected and appreciated today. LC9 A smaller version of this engine was produced in 1978 and 1979 for the Century, Regal and Chevrolet Monza. The bore was reduced to , resulting in an engine of piston displacement. The RPO code was LC9. Initially this engine produced , but in 1979 it received the same improvements in the cylinder heads as did the LD5, and therefore power increased to . LC4 In response to rising gas prices, a larger version of the 3.8 liter LD5 V6 was produced from 1980 through 1984 and marketed as an alternative to a V8. The bore was enlarged to , yielding an output of and . This engine was used in many large rear-wheel drive Buicks, and in some models from each of GM's other divisions, including Cadillac which offered the "big" Buick V6 in several models from 1980 to 1982 as a credit option to the troublesome V8-6-4 engine used in 1981 and early versions of the aluminum-block Cadillac HT-4100 V8 introduced in 1982. It was also the standard powerplant in the front-drive Riviera and Oldsmobile Toronado from 1981 to 1984. Additionally, the 4.1 block was used unsuccessfully at Indianapolis for racing. Its only weakness was the intake valve seals. This was the first naturally aspirated GM V-6 to feature a 4-barrel carburetor. 1980–84 Buick Electra 1980–84 Buick LeSabre 1982–84 Buick Regal 1981–84 Buick Riviera 1980–82 Cadillac DeVille 1981–82 Cadillac Eldorado 1980–82 Cadillac Fleetwood 1981–82 Cadillac Seville 1981–83