The Pontiac 400 6.6 Liter engine was first introduced in 1967. This version of the Pontiac V8 engine was used in the GTO, Firebird, and the Trans-Am Firebird.
The 400 was inspired by the Pontiac 389 V8 and proved to be the last Pontiac engine with closed chambered heads. At the start of the 1970s, the 400 V8 generated more than 300 horsepower, but decreased to 180 horsepower by the time the last 400 engine was produced in 1978. The special edition black and gold Trans Am made famous by Burt Reynolds in the Smokey and the Bandit movie franchise increased Firebird sales in 1977 and 1978 and made the 400 V8 quite popular. Even though production of the 400 had ceased, 1979 Pontiac models still featured the 400 engine due to large stockpiles left over from the previous year.
In 1980, Pontiac decided to use the Pontiac 301, 4.9 V8 engine to replace the 400. Sales and the new engine’s performance failed miserably and the 301 was no longer offered by Pontiac after 1981.
1967-1970 with 4-Barrel CarbMax Brake Horsepower = 330@ 4800rpmMax Torque = 430 @ 3000 rpmStroke = 3.75Bore = 4.1212Compression = 10.5Firing Order = 18436572 1967-1970 High Output with 4-Barrel CarbMax Brake Horsepower = 335@ 5000rpmMax Torque = 430 @ 3400 rpmStroke = 3.75Bore = 4.1212Compression = 10.5Firing Order = 18436572 1967-1970 Ram Air III with 4-Barrel CarbMax Brake Horsepower = 345@ 5000rpmMax Torque = 430 @ 3400 rpmStroke = 3.75Bore = 4.1212Compression = 8.0Firing Order = 18436572 1967-1970 Ram Air IV with 4-Barrel CarbMax Brake Horsepower = 370@ 5500rpmMax Torque = 445 @ 3900 rpmStroke = 3.75Bore = 4.1212Compression = 8.0Firing Order = 18436572 1971 with 4-Barrel CarbMax Brake Horsepower = 300@ 4800rpmMax Torque = 400 @ 3600 rpmStroke = 3.75Bore = 4.1212Compression = 8.0Firing Order = 18436572 1972 with 4-Barrel CarbMax Brake Horsepower = 250@ 4400rpmMax Torque = 325 @ 3200 rpmStroke = 3.75Bore = 4.1212Compression = 8.0Firing Order = 18436572 1973 with 4-Barrel CarbMax Brake Horsepower = 230@ 4400rpmMax Torque = 325 @ 3200 rpmStroke = 3.75Bore = 4.1212Compression = 8.0Firing Order = 18436572 1974 with 4-Barrel CarbMax Brake Horsepower = 225@ 4000 rpmMax Torque = 330 @ 2800 rpmStroke = 3.75Bore = 4.1212Compression = 8.0Firing Order = 18436572 1975 with 4-Barrel CarbMax Brake Horsepower = 185@ 3600rpmMax Torque = 310 @ 1600 rpmStroke = 3.75Bore = 4.1212Compression = 7.6Firing Order = 18436572 1976 with 4-Barrel CarbMax Brake Horsepower = 185@ 3600rpmMax Torque = 310 @ 1600 rpmStroke = 3.75Bore = 4.1212Compression = 7.6Firing Order = 18436572 1977 with 4-Barrel CarbMax Brake Horsepower = 180@ 3600rpmMax Torque = 325 @ 1600 rpmStroke = 3.75Bore = 4.1212Compression = 8.1Firing Order = 18436572 1978 with 4-Barrel CarbMax Brake Horsepower = 180@ 3600rpmMax Torque = 325 @ 1600 rpmStroke = 3.75Bore = 4.1212Compression = 7.6Firing Order = 18436572 