The early years of the 1960s were time-stamped with the mark of the dinosaurs—behemoth 1962 406 Galaxies, 421 Pontiac Catalinas, and 409 Chevrolet Impalas stomped the earth. On the dragstrip, these big-block production cars attracted crowds nearly as large as those for the much faster and much noisier purpose-built dragsters. Each marque's true believers wanted to see their chosen brand stomp the competition.
Hayden Proffitt won class at the 1962 Winternationals, and that included a nearly 4-foot-t
The American Manufacturers' Association's (AMA) 1957 ban on racing had thankfully lost support (because performance was selling!), and Pontiac was enjoying the fruits of conquering the competition on NASCAR oval tracks and the NHRA's increasingly popular dragstrips. On the street, It was often a 389ci Pontiac, not a Chevrolet, that the fast guys were wheeling. Guys like Don Gay were winning races with A/Stock Pontiacs, and you could drive that same Catalina right off the showroom floor.
In the 1960s, there was no more inventive car crafter than Mickey Thompson. So it was not surprising that he persuaded the suits to let him champion the Pontiac name into the record books. In 1960, Thompson had been the first man on earth to hit 400 mph with a streamliner powered by four normally aspirated Pontiacs. It wasn't a world record because the car broke on the return run, but he was still fast.
This undercarriage shot reveals an effort to fit a B&M hydro transmission to the car,
Unfortunately, while the streamliner effort revealed Pontiac power, it didn't promote production cars, which was really what Pontiac wanted. Thompson already knew how to win races; all he needed was the right car. If there is one unalterable rule for building a performance car, it's that you put the strongest engine in the lightest car. In late 1961, Pontiac shared something new with Thompson, a brand-new car called the Tempest. It was Pontiac's version of the new GM compact car, similar to the Buick Special and Olds F-85. With its four-cylinder engine, the Tempest weighed 2,785 pounds and rode on a short 112-inch wheelbase that looked miniscule compared to a Wide Track Catalina that outweighed it by nearly 900 pounds. The 1961 Tempest attracted no attention from drag racers because of its weak slant-four engine, which was one-half of a 389. The Tempest also came with a weird swing arm independent transaxle assembly, first used on the Corvair. This fact alone placed it neatly into leper status with performance buffs. Who would want a 1961 Tempest when you could buy a tri-power 389 Catalina or a 409 Chevy? But the fates were aligning in Thompson's favor, when he connected the dots to a brand-new NHRA drag racing class called Factory Experimental.
A/FX allowed Super Stock–legal engines to be transplanted into any car of the same marque. It was as if NHRA was inviting Thompson to stuff Pontiac's vaunted, twin four-barrel Super Duty 421 engine into this lightweight chassis. The only other real contender was the Chevy II with a transplanted 327 and a four-speed—Chevy didn't get the hint for production until 1965—and Tasca Ford was still months away from prototyping its 427 Fairlane.
Proffitt used a fullsize Pontiac rear axlehousing and narrowed it to fit under the Tempest
Thompson enlisted Hayden Proffitt to cut up a new Tempest that Hot Rod magazine quickly chronicled ("Thompson's Terrible Tempest") in the Sept. 1962 issue. Proffitt immediately removed the clumsy two-speed transaxle and replaced the spindly piece with a more traditional manual transmission and a narrowed, fullsize Pontiac rear axle. The Super Duty 421ci engine actually fit into the Tempest's engine compartment; that was the easy part. The factory transaxle configuration required only a small hump in the floorpan for clearance and was otherwise nearly flat, prompting Proffitt to cut much of the floor to clear the traditionally located heavy-duty Pontiac three-speed manual transmission. Thompson showed up at the NHRA Winternationals with Proffitt driving and cleaned house, while running low 12s. That got everybody's attention. By the Indy Nationals in September, there were several Tempests in attendance, but Lloyd Cox drove the Thompson entry, and once more the team took the A/FX class trophy.
Among the SD 421 components were these now ridiculously rare, long-tube factory cast-alumi
The major fabrication work was performed at the rear of the car, and it began when Proffit
As you can see, the 421 Super Duty was an easy fit in the Tempest engine bay. Left-side he
Here, we see the sheetmetal work required to adapt a manual transmission underneath the st
It may not look like it, but this is the interior of a class-winning A/FX Pontiac in 1962.
According to the Hot Rod story, the only changes to Mickey Thompson’s stock 421 Super Duty
Just a few months hence, 1963 would prove to be the pinnacle of GM participation in all things racing. Mickey Thompson and Royal Pontiac's successes on the dragstrip with the Tempests and Super Duty Catalinas set the wheels in motion to construct 14 cars—six Le Mans coupes and six Tempest wagons, and then later two more Tempests coupes were constructed, all in white with 421 SD engines. But these cars came with a twist. They retained the transaxle and independent rear suspension (IRS). All production Tempests came with a two-speed automatic transaxle (called the Tempest Torque) that was modified by Pontiac Engineering with a second planetary gearset added to the rear of the transaxle, transforming the two-speed into a four-speed called the Powershift. According to Tempest owner Tom Schlauch, he witnessed two of these cars being delivered to Jess Tyree's shop.
At the 1964 Indy Nationals, Arnie "the Farmer" Beswick drove this Tempest coupe owned by M
According to Schlauch, the cars he witnessed were equipped with a clutch, but it's possible that a few came with a fluid coupling, which is very inefficient because it lacks the stator that multiplies torque. A few Tempests attempted to run fluid couplings, but none were successful. Unfortunately, breakage was a big problem. Schlauch says that most of the cars could get roughly 10 runs out of a ring-and-pinion before they failed. This eventually forced most of the SD Tempest racers to convert to the traditional solid rear axle and transmission configuration. Schlauch says there are four surviving original SD Tempests, and three of them retain the incredibly rare original transaxle and the so-called "rope" driveshaft. The actual production Tempest driveshaft was in reality a solid, 3⁄4-inch bar that was encased in a torque tube that incorporated a significant fore-aft bend in the tube to create less of an intrusive tunnel in the floorpan.
The 1963 factory cars also enjoyed even more exotic weight reductions. Part of the Tempest weight-loss plan was to offset the fact that the 1963 redesigns were heavier, due to the 5 additional inches of overall body length and 2 inches in width. The low-calorie program included an aluminum front end, including fenders, hood, lower valence, and grille surround. Aluminum bumpers on the early cars proved too thin and were replaced by acid-dipped steel versions. The idea behind the wagons followed Junior Stock theory that the additional rear weight would improve traction, but the extra 200 pounds hurt elapsed times so that the sedans were considered the most desirable.
Here’s the 672 car at the 1962 Winternationals, probably during qualifying. Also note the
Thompson continued his winning ways, with Bill Shrewsberry driving his 1963 car to take the Winternationals A/FX class win with a 12.04 at 116.29 mph. By now, the NHRA had also created B/ and C/FX classes for lower horsepower configurations and times for all the classes were dropping fast. By the end of the year, the A/FX record was still held by a Tempest with Arlen Vanke running an accredited 11.89/123.11 pass. While Chevy, Ford, and Chrysler had been caught napping the year before, the factory teams quickly stepped up their game, and Dave Strickler won the A/FX class trophy at the 1963 Nationals, driving a 427ci Z-11 Impala.
There was certainly more development that might have kept Pontiac in the limelight of the quarter-mile drama, but the axe fell at the end of 1963 when GM "officially" pulled out of active participation in motorsports. Pontiac followed the rules and retired all its factory drag racing support, while Chevrolet continued a clandestine effort. This corporate push to avoid racing came about due to pressure from the federal government that believed GM was approaching a near monopoly on auto sales in the U.S. Since Ford and Chrysler were the underdogs, they could continue to fund and support racing programs, and by the 1964 Nationals at Indy, the once-heroic Tempests were already outclassed. As often happens, most of the racers who had championed Pontiacs a few years earlier moved on to Fords, Chevys, and Mopars. Even Thompson transferred his allegiance to Ford by the end of 1963. It was the end of Pontiac's drag racing domination.
Apparently, Thompson performed some minor sheetmetal work probably to fit the larger wheel
Bill Shrewsberry drove the number 755 Mickey Thompson ’63 Tempest to win A/FX at the ’63 N
A trunk photo of the first Thompson car reveals a smooth floor and the addition of a batte
Perhaps even more obscure than the drag racing Super Duty Tempests were even fewer 421-powered Pontiacs that made their way onto to road courses and oval tracks soon after Mickey Thompson's cars began invading America's dragstrips. Four cars were prepared by Nichels Engineering (in Indiana) for the inaugural NASCAR Daytona Continental sports car race in 1962, but only one finished.
Pontiacs returned to Daytona in 1963 with a strong car entered by Nichels and driven by Paul Goldsmith. In a wet Daytona American Challenge Cup race on the big oval, the little Pontiac bested a Mystery 427-powered 1963 Corvette owned by Mickey Thompson, a Cobra, and other import cars, including a Ferrari. The next day, in a contest called the Continental Cup race, the Tempest unfortunately retired with what was later attributed to driveline failure.
Goldsmith's number 50 car used the similar twin four-barrel 421 Super Duty engine but retained the intriguing four-speed Powershift factory transaxle assembly. This design used a clutch located at the very back of the transaxle but only employed it to launch from a dead stop. Once moving, all gear changes were made without the use of the clutch by merely moving the gear selector, although shifting in this manner probably contributed to the early transaxle failures. Major suspension changes had been applied to the original swing-axle design to improve the handling, and the car was clearly competitive. Unfortunately, this factory-enhanced effort was discontinued soon after the Daytona race in deference to Washington, D.C. sabre rattling.
This 1963 Tempest was driven by Paul Goldsmith at a time when road race and stock cars wer
This photo of the Number 50 road-race Tempest reveals an additional fuel tank. This image
This is the eight-barrel 421 that powered the Goldsmith’s road racer.
The Super Duty 421
The 421 Super Duty took Pontiac's very successful 389 and made it bigger all the way around. They increased the bore by 0.030 inch to 4.093 inches and added a 0.250 inch to the stroke for a total of 4.0 inches. The first 421 Super Duty appeared as a dealer-installed engine in 1961, followed as optional engines for the Catalinas and, of course, the SD 421 Tempests in 1963. In that year, there were three different Super Duty 421 configurations. The single four-barrel version was factory-rated at 390 hp, sported 12:1 compression, and was intended for NASCAR stock car racing. Adding another carburetor to the same engine pushed the second version to 405 hp. Pontiac's big dog in the factory horsepower hunt retained the twin four-barrel induction but added another point of squeeze to 13:1. Rated at a ridiculously conservative 410 hp (500–550 hp is more realistic), this engine was intended for drag racing.
Thompson took the car to Indy in 1962 (as number 972) and promptly won class running a 12.
All SD engines were equipped with forged crankshafts, forged pistons, and 3.250-inch main journal diameters, increased over the 389's already large 3.00-inch journals. Rod journals remained the standard Pontiac size of 2.250 inch. Four-bolt main caps were also standard. Iron Super Duty cylinder heads (the 980 head carried the late 1962 and 1963 casting number, while earlier 1962 engines received 127 heads) and to keep the inlet air temperatures cooler, both units were built without the usual heat-riser passage. All SDs also came with one of three mechanical lifter camshafts, referred to as McKellar cams, in reference to Pontiac chief powerplant engineer Malcolm "Mac" McKellar, who was responsible for their lobe designs. McKellar also designed not just camshafts but also oversaw the creation of the SOHC inline-six and many of the exotic DOHC engines that Pontiac experimented with in the late 1960s.
The Super Duty 421 engines also spawned a number of interesting factory-inspired performance components. If you were connected to the pipeline in 1963, you might have scored one of perhaps as many as 40 or 50 two-piece "bathtub" tunnel ram intakes cast by Pontiac. Other unique pieces included a three-barrel Carter AFB carburetor (PN 3636S) intended for NASCAR circle-track engines. Due to the GM corporate ban of late January, 1963, all engine production halted. While successful in killing Pontiac's factory support of racing, this performance ban would last only a few months until Pontiac again pushed the envelope with the more street-worthy '64 GTO.
Pete McCarthy Publications; 714/997-5856; PeteMcCarthy.com
Little Indians Chapter of the Pontiac Owners Club, International; LittleIndians.com