Pontiac’s Last SD-455 Powered Performance Car
At a time when the Arab Oil Embargo and Federal emissions standards killed the muscle car era, one name bucked the trend … when the smoke faded the Pontiac Trans Am Super Duty was the last muscle car standing.
Those who try to compare the SD-455 with Pontiac’s other big block motors are making a mistake. The boys in Pontiac engineering department really pulled one on GM corporate. According to Douglas Sciberras, author of the book “Miscellaneous Ramblings of a ’70s Motorhead,” many of the components and designs for the full bore racing engine that became the SD-455 came from Pontiac’s 366 ci NASCAR program. The SD-455 was designed to be a racing engine, then “tuned down” to appease the EPA. With a little wrenching the engine would provide all the ground pounding excitement your heart can take.
With its nodular-iron crank, bullet proof forged iron rods and TRW forged-aluminum pistons and free flowing cast iron heads and heavy duty oil pump it was a serious muscle car. The key to the its performance were the free-flow heads. Pontiac engineers really had this down. Think about it. A low-compression big block that generated 310 horsepower. (The EPA found out about Pontiacs free breathing system and forced Pontiac to downgrade the engine to 290 hp.) The acceleration was so powerful it reminded sports car fans of the muscle car era. According to the factory promotional materials, the SD-455 Trans Am would do 0-to-60 mph in 7.3 seconds, while it would do a quarter-mile in just 15 seconds. The way to tell if your car is a real SD-455 Trans Am from 1973 or 1974 is to look at the VIN number. The X in the VIN denotes SD-455.
The 1974 Pontiac Trans Am Super Duty which you see pictured here was just listed for sale by Midwest Car Exchange out of Alsip, Illinois. It has the matching code W8 which means it is a4-speed, and is one of only 212 such cars built. Only 943 Trans Am SD-455’s were produced altogether in 1974. The Buccaneer red treasure is a show winning rotisserie restoration with full paperwork from day one, a build sheet and PHS documentation. This according to the description recorded by Midwest Car Exchange. It also has a ton of power options, including power disc brakes, power steering, power windows and power door locks.
The amazing SD-455 big block engine that roared under the hood of the Super Duty Trans Am was a modern era high performance gem the likes of which Detroit had not seen before. Even though it had restricted horsepower and a mild cam, the single Quadrajet Rochester carburetor provided enough torque to blow away most of the earlier cars in the muscle car era. At a time when Plymouth Cudas, Corvettes and Chevelles were being de-tuned because of insurance costs and emissions controls, the Trans Am was the only American sports car that continued the muscle car tradition. For the time being, the Super Duty Trans Am with its legendary SD-455 was the only big block car that kept the American dream alive.
The most desirable SD-455 cars are the Canadian Pontiac models. They had functional hood scoops which was legal in Canada.
This car has been SOLD.
Pontiac enthusiasts thought this 1974 Pontiac Trans Am Super Duty was too good to be true, and history proves they were right. The emergence of catalytic converters ended the short reign of the SD-455 Trans Am as America’s last muscle car.