Pontiac Trans Am Super Duty - 2nd Gen (1973 to 1974)

For the 1973 and 1974 model years, Pontiac offered an extra option for the 2nd Gen Trans Am, the Super Duty 455ci V8. These cars had a unique hand-built engine from the factory. The SD-455 motor was based on the already produced 455ci and put out about 290hp/395lb-ft of torque. As the name implies, the engine wasn't just about performance; it was about durability. The engine had added material throughout the block and 4-bolt main to handle additional power and other modifications. 252 SDs were built in 1973. The SD could be ordered on the Formula model as well.