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1963 Pontiac Tempest Coupe 421 Super Duty

1963 Pontiac Tempest Coupe 421 Super Duty

1963 Pontiac Tempest Coupe 421 Super Duty

Long known as the preferred brand of the senior set, Pontiac roared out of nowhere at the turn of the Sixties to claim multiple Super Stock championships. It kept the competition back on its heels with a flurry of new over-the-counter parts before finally introducing a radical new performance package that was more than the typical recipe of cubic inches, midsize body and deleted creature comforts.

Pontiac engineers had decided not only to up the horsepower ante, but to address the major problem facing their drag-racing customers: traction. The new Super Duty Tempest/Le Mans Coupes, like the SD Tempest station wagons, used a rear-mounted transaxle for better weight distribution, improving the car’s launch. Heavy-duty internals were packed into new, stronger cases, creating the unique and durable “Powershift” four-speed transaxle. A robust mechanical clutch could be used to replace the torque converter, adding to starting-line response.

The factory took further steps to improve the car’s performance, punching its 389 V-8 out to 421 cubic inches. Its twin 4-barrel carbs and free-flowing aluminum exhaust headers pushed power up to a potential 500 horses, and lightweight aluminum front sheetmetal and bumpers shaved considerable weight.

Chassis & Sales

The Wynn Engineering Tempest presented here is one of the original six 421 Super Duty Coupes built by Pontiac. Four were destroyed and a fifth was recently found minus almost all the distinguishing special factory equipment, making this car the only complete example in existence. Along with the Union Park SD station wagon, it has been a central piece of Dana Mecum’s collection of rare Pontiac factory racers.

It was sold at Dana Mecum’s 2010 Original Spring Classic Auction for $455,000 USD.

Story by Mecum Inc.

In Detail

type Racing Car
built at USA
production 6
engine Super Duty 90º V8
position Front, Longitudinal
aspiration Natural
valvetrain Pushrod OHV
fuel feed Dual Carter Carburetors w/Bathtub Ram Intake
displacement 6899 cc / 421 in³
compression 12.0:1
power 302.0 kw / 405 bhp @ 5600 rpm
specific output 58.7 bhp per litre
bhp/weight 269.64 bhp per tonne
torque 576.2 nm / 425 ft lbs @ 4400 rpm
body / frame Steel Body w/Aluminum Fenders & Hood over Pressed Steel Chassis
driven wheels RWD
curb weight 1502 kg / 3308 lbs
transmission T-85 3-Speed Transmission
final drive 4.30:1