Chrysler's Motown Missile: Mopar's Secret Engineering Program at the Dawn of Pro Stock
late 1967, retiring their ever-evolving Funny Car and turning the Top Fuel car over to a mostly outside crew. After all, the exploding muscle car business had grown into a big part of vehicle marketing, which was further spurred on in 1967 when the NHRA divided its raced stock cars between a Junior Stock–style lower division simply named “Stock” and a new standalone Super Stock division to showcase the best factory cars and drivers.
Ever scientific in approach, Hoover knew testing was paramount to this division’s success. As a result, select factory-associated cars and drivers began showing up one day a week at Motor City Dragway near Mt. Clemons, Detroit Dragway at Sibley, Dix south of downtown, Milan Dragway west of the city, or even a faraway location such as a track in California when the racing season started. Rented by the company for private use to experiment with new ideas such as hood scoop shapes, special tires, or promising cam designs, these test sessions became part of the legend of Chrysler Engineering “doing so much with so little.” By 1969, Al Adam, yet another Ramcharger alumni, was managing that aspect of real-world testing with Spehar doing the engine prep; both men were meticulous at record-keeping. Edited notes on successful experiments were forwarded to Chrysler racers across the nation.
Some tests were done with cars recently prototyped in an offsite-from-Engineering location simply known as the Woodward Garage. Located in a former Pontiac dealership at the corner of Woodward and Buena Vista in Highland Park, this small private shop served as the skunkworks for ideas that Hoover or his compatriots dreamed up for racing under factory authorization or for special projects done on existing cars. UAW shop steward and top mechanic Larry Knowlton was the unofficial manager at the garage.
During late 1967 and early 1968, at Mr. Hoover’s request, Knowlton and a brilliant, somewhat flamboyant young engineer named Robert “Turk” Tarozzi reworked a Race Hemi into the small Plymouth Barracuda. Once they put it all together, the result was one of the most notorious drag racing combinations ever authorized by Detroit. That spring under contract for Chrysler, shifter-company-turned-vehicle-constructor Hurst Industries converted approximately 160 of these A-Body models (both Barracudas and Dodge Darts) into Hemi-powered drag-race-only machines in a Detroit-area facility. They came to conquer under the tutelage of factory-favored drivers, such as Ronnie Sox, Arlen Vanke, Don Grotheer, and Dick Landy. By then, Dave Koffel, a trained metallurgist who had been racing himself for many years, handled the deals with the racers.
Development in the 1967–1968 era resulted in what many still consider the ultimate Chrysler race package: the Hurst Hemi package cars. This is the first Sox & Martin 1968 Barracuda, seen here at its initial drag test session at Cecil County Dragway in Maryland in April 1968. (Photo Courtesy Tom Hoover Archive)
Again, the rule makers were stymied. Reams of correspondence from Hoover, Koffel, Product Planning’s Dick Maxwell (yet another former Ramcharger), and others were sent out to NHRA officials in California, asking pointed questions about the factored horsepower the NHRA had placed on Chrysler engines, why Ford was allowed to run a combination no one in Detroit had seen except in the hands of that company’s best-known drivers, or why the new Six Pack Road Runners and Super Bees had no owner lists because they were actually sold as “street cars.”
This signed letter to the NHRA was among many that went back and forth between the factories and the NHRA in those days. Tom Hoover was always looking for an advantage, although he later admitted that the NHRA never forgave Chrysler for some of the things it did, such as the 1969 Mini-Nationals. (Photo Courtesy QMP Research Files)
Though perhaps frustrating, Mr. Hoover was always all-in on this game, figuring out the rule book, finding scarce racing combinations that had an advantage, and pushing the envelope. At times, those creative solutions likely had NHRA president Wally Parks cursing quietly at the sheer genius of it. At the same time, one of his angry division directors called NHRA tech boss Bill “Farmer” Dismuke at the organization’s North Hollywood offices to complain about what “them Chryslers” had done to the record book the past weekend. Hoover would laugh for a moment, then go right back to work to “crush them like ants,” as he was prone to state in private company.
It all came to head at the 1969 NHRA Nationals held in Indianapolis over Labor Day weekend. The NHRA knew that the best drivers in Super Stock (a very popular class by that time with factory attention) were hitting the brakes well before the finish line to keep from showing their top performances. At that time, if your car went too fast, you lost. Basically, any performance made during eliminations that exceeded the current NHRA elapsed time index broke out, going beyond its established performance. When that happened, the car was disqualified from advancing to the next round.
Super Stock: Racing on the Brakes
Each Super Stock car had a set elapsed time index. This was derived from the possible performance of that combination based on an NHRA-factored horsepower-to-weight ratio. Each engine was rated for horsepower as estimated by the NHRA’s Technical Committee, which in turn was coupled to the manufacturer’s stated overall weight for each car as released off the assembly line. Weighed without driver, the engine/car package would then fall into a select letter category. For example, “A class” was the highest horsepower/lightest car combination, followed by B, C, D, etc. Automatic and manual transmissions were further broken into their own subgroups in each class to provide additional equality; automatic-equipped models had an A after the class letter.
At big events, each group of identically classed cars raced each other for a class victory among peers, and winners then advanced to final eliminations. At smaller races, the driver would simply be timed against the index. Once racing among all those classes was underway, the slower-classed car was given a head start by whatever the calculated index difference was.
During the 1969 season, entries in the Super Stock classes ranged from SS/B (solely the Hurst Hemi cars because no one had built a car in a weight legal in SS/A at that time) through SS/J. A like number of cars were classified in the automatic transmission classes that were identified with an additional A at the end of the classification. So that year, the 10 class letters and 2 transmission choices meant 20 possible classes.
Originally stated as an NHRA-set minimum elapsed time, the index for each class in 1969 was based on the current class record for that class. No one wanted to beat that record if possible because it left no room for error. In other words, resetting a soft index record might make winning less possible by requiring the maximum effort on every single run. Furthermore, changing the record would affect every driver racing that combination, not just the cars capable of running to that level. As a result, and sometimes at factory direction, the fastest cars were often braking at over 100 mph to prevent this from happening.
Hemi race car drivers, such as Dick Oldfield in New York and Don Carlton in North Carolina, were familiar with this technique. It was dangerous, and the racers frankly hated it. Pro Stock would eventually solve this problem for many of them.
So, going into their biggest event of the year, the NHRA decided to catch the racers at their own game. This was when the NHRA stated that at Indy every run down the track could become the index for Monday’s finals. Since only the class winner and runner-up from Saturday afternoon’s class runoffs were allowed to advance to race in Monday’s final eliminations, these new racing indexes would obviously be derived from the fastest runs made during that weekend. This was because the NHRA assumed every driver would have to run flat out to win a class crown. Still, to make it fair, they also agreed that the index would not change again on Monday. For the first time, drivers could run flat out all day and the record rule would not apply until the final. In the final round, the drivers could run as fast as necessary, but that fast time was the new index heading into the following event.
On Friday morning, the Chrysler racers slowly left town, heading for a little track just over the Ohio state line a couple of hours east. Dave Koffel rented the track with his American Express card, and now each of the three-dozen-plus drivers arriving there would