Our man on the track, Stephen Cox, talks with Richard Petty about his connection to the winged Superbird.
It has been claimed that Plymouth’s legendary winged ‘70 Superbird was the brainchild of NASCAR champion Richard Petty. The rumor has been around for decades but I’ve never found anyone with first-hand knowledge who could absolutely confirm or deny that the car’s origins truly began with The King of Stock Car Racing.
But opportunity knocked a couple of weeks ago when Petty was in attendance at the Mecum auction in Kissimmee, FL, which I co-host for NBCSN. I found him relaxing backstage late in the show and hollered, “Hey, King!” Although I don’t know him well, he looked up with his trademark smile and immediately held out his hand.
I asked him point blank whether he was responsible for the development of the Plymouth Superbird. Petty paused and laid the back of his hand across his brow. “Well, let me get the dates right.”
“We knew in 1968 that Dodge was building a wing car. So I went to Plymouth and asked if they were gonna build one and they said, ‘No.’ I told them that I’d like them to work on one and they said, ‘No, you’re winning all the races anyway.’”
True, Petty had been dominant, winning 27 of 49 Grand National races en route to the championship in 1968. Rather than cough up the additional funds to stay current in NASCAR’s burgeoning aero wars, Plymouth was content to let Petty struggle against increasing odds.
Undeterred, Petty tried another angle. He asked if he could stay within the Chrysler family and simply move over to Dodge and drive the new Charger Daytona winged car for the 1969 season. Plymouth flatly refused.
“So I said, ‘Either build me a wing car or I’m walking across the street,’” Petty continued. “They said, ‘Sure, go ahead.’ So I did.”
That same afternoon Richard Petty personally walked into Ford Motor Company’s front office. Ford executives took no risks, signing Petty to a one-year contract on the spot. Petty finished second in the points chase while winning ten races for Ford in 1969. It was enough. He didn’t have to return to Detroit to beg Plymouth for a winged car. This time, they came to him.
“The head man from Plymouth came walking into my shop,” Petty continued. “He said, ‘What do we need to do to get you back? I said, ‘Give me what I’ve been asking for.’”
Plymouth pledged to have a new winged car completed for Petty in time for the 1970 NASCAR season. Rather than re-inventing the wheel, they chose to use a modified version of the wildly successful Dodge Charger Daytona platform. Under NASCAR’s homologation rules, a limited number of Superbird street cars were built and sold through Plymouth’s dealership network.
Behind the wheel of the car built specifically for him, Richard Petty and his Plymouth Superbird won 18 of the 40 races in which they competed in 1970, led nearly half of all laps and won nine pole positions. Despite being produced for only one model year, the road-going version of the Superbird became a legend in the annals of musclecar history.
Today, a concours-ready Plymouth Superbird will routinely draw bids from $100,000 to $300,000 at auction. They remain among the most collectible musclecars ever built.
“So there you go,” Petty told me with a smile. “That’s how it happened.”
Cadillac’s all-new Cadillac DPi-V.R racecar will compete in the 2017 IMSA WeatherTech SportsCar Championship Series, Prototype (P) class.
The Cadillac DPi-V.R will first be driven competitively at the 2017 IMSA season opener – the Rolex 24 At Daytona on January 28-29, 2017. Wayne Taylor Racing and Action Express Racing teams will field it. IMSA’s WeatherTech SportsCar Championship is the fastest and most technologically advanced sports car racing series in North America.
“Cadillac is proud to return to the pinnacle of prototype racing in North America after a 14-year absence,” said Johan de Nysschen, president of Cadillac. “Cadillac’s V-Performance production models – the ATS-V and CTS-V – are transforming our brand’s product substance, earning a place among the world’s elite high-performance marques. The Cadillac DPi-V.R further strengthens our V-Performance portfolio, placing Cadillac into the highest series of sports car racing in North America.”
The DPi-V.R has been designed to contribute to the functional performance of the prototype using elements gleaned from the current lineup of Cadillac V-Performance models, especially the CTS-V. The racecar is equipped with the new Rear Camera Mirror, first seen on the Cadillac CT6 Sedan and available on the 2017 Cadillac CTS, XT5 and Escalade.
“The DPi-V.R racecar was an exciting new canvas for the Cadillac design and sculpting team,” said Andrew Smith, Global Cadillac Design executive director. “The studio embraced the opportunity to interpret the Cadillac form language, line work and graphic signature for this premier prototype racing application.”
Design details giving the DPi-V.R car its distinctive Cadillac appearance and presence include the vertical lighting signature; the sheer, sculptural quality of the body and bold bodyside feature line. Plus, V-Performance wheels, Brembo brakes, V-Performance emblems, and a canopy graphic inspired by the Cadillac “daylight opening.” Even subtle cues such as the cooling vents and the air intake were designed in the studio, the latter in the trapezoidal shape of the Cadillac crest.
A, race-prepped, naturally-aspirated 6.2-liter V-8 that shares architecture with Gen III Cadillac CTS-V (640 horsepower) and Gen V Cadillac Escalade (420 horsepower) engines, powers the DPi-V.R. The engine produces approximately 600 horsepower when tuned for racing as defined by IMSA-mandated air restrictors, with a maximum allowable rpm of 7,600. The engine transfers power to the rear wheels through an X-TRAC paddle-shift transmission.
Cadillac and its designers collaborated with key partners including chassis builder Dallara, teams from Wayne Taylor Racing and Action Express Racing and ECR Engines to prepare the 6.2-liter V-8-powered Cadillac DPi-V.R over the past year.
Stephen Cox blogs about Shelby American’s legendary Group 2 Mustang racers, Part 3 of 3.
John McComb ordered a new car for 1967. The choice was easy. Given his success in the 1966 Group 2 Mustang, he ordered a new notchback for 1967 to pick up where he left off with the Shelby program. The ‘67 Mustang was the model’s first major redesign and the car gained both size and weight. McComb didn’t care for either.
“Even though the ’67 car had a wider track, it was a heavier car, so I don’t really think the wider track helped,” McComb said. “The ’66 car was just a very reliable, quick car. I always thought the ’66 was better than the ’67 anyway.“
While awaiting delivery of the new car, McComb pulled his old mount out of the garage to start the new season. It still ran strong, competing at the Daytona 300 Trans-Am race on February 3, 1967 and in the 24 Hours of Daytona the following day. In March, McComb returned to familiar grounds and took second in the amateur A/Sedan race at Green Valley, and again participated in the Trans-Am event the following day. The car’s final race under McComb’s ownership was the Trans-Am at Mid-Ohio Sports Car Course on June 11th.
His new racecar became available just days later and McComb sold the #12 Group 2 Mustang to Keith Thomas, a Kansas native who had shown considerable ability winning club races throughout the region. Thomas campaigned the car against stiffening competition in the A/Sedan Midwest Division, ironically finishing second in the championship hunt only to John McComb’s new car.
This gave the #12 Group 2 Mustang a unique place in road racing history. Not only did it claim a share of John McComb’s A/Sedan championship by scoring points for McComb early in the 1967 title chase, but it also clinched second place in the same series in the hands of Keith Thomas. By virtue of Thomas’ runner-up standing in the series, the car earned a second invitation in the AARC at Daytona where it scored yet another top five finish.
Keith Thomas continued driving the #12 Group 2 Mustang in 1968 and 1969, finishing third in the series both years. Although the car was now well past its prime, Thomas set a new A/Sedan track record while winning at Wichita’s Lake Afton Raceway. He continued to rack up wins at places like Texas International Speedway, Oklahoma’s War Bonnet Park and the SCCA Nationals at Salina, Kansas throughout the late-1960s.
Now sporting a new livery, the car ran a limited schedule from 1971-73, after which it was retired from auto racing. The car traded hands later that year and again in 1978, each time distancing itself a bit more from its proud past while being repeatedly repainted and renumbered. Finally, in 1984, the car came into the possession of car collector Gary Spraggins. By this time its true identity had been lost and Spraggins was unsure of its provenance. He bought the car anyway.
Spraggins recalled that the Mustang had been repainted in “school-bus yellow” with black Le Mans stripes. There were no Shelby markings to be found anywhere on the car, but still Spraggins suspected that the vehicle might be something special. He noticed several items that were unique to Shelby GT350Rs, including the Cobra intake manifold, the Holley 715 carburetor and the A-arms that had been relocated to lower the car by one-inch. Mechanically, everything about the car screamed “Shelby” although no one really knew for sure.
The moment of truth came when Spraggins took the car home for a closer inspection. “When I raised the trunk lid up, of course, the inside of the trunk area was black, but you could see the Le Mans stripes overspray down in there,” Spraggins remembered.
“Oh, man, I knew what those colors represented – Shelby cars. And I got some paint remover and lightly put it over the black Le Mans stripe on the trunk and wiped it off, and there was the prettiest blue Le Mans stripe there. It’s like, oh, my gosh!”
Spraggins immediately wrote to the Shelby American Automobile Club, describing the car and asking if the VIN could be verified as a Shelby product. The response came on November 12th.
“Looks like you’ve found one of the original Shelby 1966 Trans-Am cars,” the letter began. “Your car was originally sold to Turner Ford in Wichita, KS. I think they may still be in business…”
SAAC national director, Rick Kopec, signed the letter. And so did Carroll Shelby.
Spraggins could barely contain his enthusiasm and quickly set to work restoring the car to its original 1966 livery and condition, not realizing that an aging John McComb had also entertained the idea of finding his old mount. He just didn’t know where to look.
“I was very excited at that time that I had found a needle in a haystack,” Spraggins said. “Nobody knew anything about these cars, so in order to track down the original driver – you know, John McComb – I just started calling information in the Wichita area.”
On a hot summer afternoon in late-July 1985, the telephone on John McComb’s desk rang again. On the other end was car collector Gary Spraggins calling with the surprising news that his famous #12 Group 2 Mustang had been found. When McComb saw photos of the newly restored Mustang, he said, “My immediate reaction was, ‘That’s my car!’ What a super job you have done on it.”
When asked to critique the restoration and help them convert the car to its precise 1966 condition, McComb confessed to a pair of secrets that he’d kept for nearly 30 years.
“We cheated in two places on the bodywork. One was on the lower front valance where the license plate goes. We took those two little tabs off and opened it up a little. We also opened up the front fenders just a little. We rolled the inner lip around a welding rod to give it more strength for nerfing. We never got caught on either one.”
Eventually, even Carroll Shelby was reunited with the newly restored #12 Group 2 Mustang at a car show in the mid-1990s. He recognized it instantly. “This was the last year I was really interested in racing,” he lamented to Mustang Monthly.
“We had won Le Mans in 1966 and then the Trans-Am series came along. A lot of our good guys had moved on to other things because we had been winning for so many years.”
When it came to North American road racing, the Group 2 Mustangs were Shelby’s last stand. Largely forgotten by car collectors worldwide, these amazing racecars won the first Trans-Am title for Ford and were among the most dominant sportscars their era. They left an indelible imprint on the American road-racing scene of the 1960s. Then they simply disappeared.
Standing at the car’s freshly repainted rear fender, Shelby crossed his arms, took one last glance at the #12 Group 2 Mustang and gave a long sigh. “After 1966, we were concentrating on building volume. Unfortunately, the racing programs didn’t have much priority after this.”
NOTE:All photos are courtesy of Mecum Auctions. The driver in the cockpit photo is owner/driver John McComb preparing for a race in the late-1960s.
The story of BMW’s turbo ‘rocket fuel’ has long since passed into Formula 1 legend, but there’s a longer and deeper story here, involving the German war effort, some organic chemistry, and the history of oil refining techniques. But let’s begin with the legend, and the breakthrough which enabled the Brabham-BMW of Nelson Piquet to win the 1983 Drivers’ Championship:
[BMW motorsport technical director, Paul] Rosche telephoned a contact at chemicals giant BASF and asked if a different fuel formulation might do the trick. After a little research, a fuel mix was unearthed that had been developed for Luftwaffe fighters during World War II, when Germany had been short of lead. Rosche asked for a 200-litre drum of the fuel for testing and, when it arrived, he took it straight to the dyno.
“Suddenly the detonation was gone. We could increase the boost pressure, and the power, without problems. The maximum boost pressure we saw on the dyno was 5.6 bar absolute, at which the engine was developing more than 1400 horsepower. It was maybe 1420 or 1450 horsepower, we really don’t know because we couldn’t measure it — our dyno only went up to 1400.” (‘Generating the Power’, MotorsportMagazine, January 2001, p37).
An aromatic hydrocarbon called toluene is commonly held to have been the magic compound in this fuel brew, but erstwhile Brabham chief mechanic Charlie Whiting goes further:
“There were some interesting ingredients in it, and toluene has been mentioned. But it would have had far more exciting things in it, I think, than toluene. I suspect – well, I know – that it was something the BMW engineers had dug out of the cupboard from the Second World War. Almost literally rocket fuel,” (‘Poacher Turned Gamekeeper’, MotorsportMagazine, December 2013, p74).
Before we delve into the chemistry of fuels, let’s establish some context here. The current F1 turbo engine regulations require detonation-resistant fuels with a high calorific value per unit mass. Detonation resistance enables one to increase the compression ratio, and thereby increase the work done on each piston-stroke, while the limits on total fuel mass and fuel mass-flow rate require fuel with a high energy content per unit mass.
In contrast, in the 1980s the regulations required detonation-resistant fuels with a high calorific value per unit volume. From 1984, the amount of fuel permitted was limited, but the limitation was defined in terms of fuel volume rather than mass, hence fuel with a high mass-density became advantageous. By this time, the teams had already followed BMW’s lead and settled upon fuels with a high proportion of aromatic hydrocarbons.
To understand the significance of this, we need to start with the fact that there are four types of hydrocarbon:
(i) Paraffins (sometimes called alkanes) (ii) Naphthenes (sometimes called cycloalkanes) (iii) Aromatics (sometimes called arenes) (iv) Olefins (sometimes called alkenes)
Methane, ethane and propane. Each larger disk represents a carbon atom; each white disk represents a hydrogen atom; and each black disk represents a covalent bond.
Each hydrocarbon molecule contains hydrogen and carbon atoms, bound together by covalent bonds. The hydrocarbon types differ from each other by the number of bonds between adjacent atoms, and by the overall topology by which the atoms are connected together. So let’s briefly digress to consider the nature of covalent bonding.
The electrons in an atom are stacked in so-called ‘shells’, each of which can contain a maximum number of members. The first shell can contain only two electrons, while the second can contain eight. If the outermost electron shell possessed by an atom is incomplete, then the atom will be disposed to interact or bond with other atoms.
A neutral hydrogen atom has one electron, so its one and only shell needs one further electron to complete it. A neutral carbon atom has six electrons, two of which fill the lowermost shell, leaving only four in the next shell. Hence, another four electrons are required to complete the second shell of the carbon atom.
In covalent bonding, an electron from one atom is shared with an adjacent atom, and the adjacent atom reciprocates by sharing one of its electrons. This sharing of electron pairs enables groups of atoms to complete their electron shells, and thereby reside in a more stable configuration. In particular, a carbon atom, lacking four electrons in its outermost shell, has a propensity to covalently bind with four other neighbours, while a hydrogen atom has a propensity to bind with just one neighbour. By this means, chains of hydrocarbons are built.
Methane, for example, (see diagram above) consists of a single carbon atom, bound to four hydrogen atoms. The four shared electrons from the hydrogen atoms complete the outermost shell around the carbon atom, and each hydrogen atom has its one and only shell completed by virtue of sharing one of the carbon atom’s electrons.
If there is a single covalent bond between each pair of carbon atoms, then the hydrocarbon is said to be saturated. In contrast, if there are more than one covalent bond between a pair carbon atoms, the molecule is said to be unsaturated.
Saturated ethane in a state of unconcealed glee compared to the glum unsaturated ethylene, and the vexatious triple-bonded acetylene, (this and the above taken image from ‘BP – Our Industry’, 1958, p69).
Now, to return to our classification scheme, paraffins are non-cyclic saturated chains, (there is a sub-type called iso-paraffins in which the chain contains branching points); naphthenes are cyclic saturated chains; aromatics are cyclic (semi-)unsaturated chains; and olefins are non-cyclic unsaturated chains, (with a sub-type of iso-olefins in which the chains have branching points).
Aromatic compounds possess a higher carbon-to-hydrogen ratio than paraffinic compounds, and because the carbon atom is of greater mass than a hydrogen atom, this entails that aromatic compounds permit a greater mass density. This characteristic was perfect for the turbo engine regulations in the 1980s, and toluene was the most popular aromatic hydrocarbon which combined detonation-resistance and high mass density.
To put toluene into context, we need to begin with the best-known aromatic hydrocarbon, benzene. This is a hexagonal ring of six carbon atoms, each one of which is bound to a single hydrogen atom. Toluene is a variant of this configuration in which one of those hydrogen atoms is replaced by a methyl group. The latter is one of the primary building blocks of hydrocarbon chemistry, a single carbon atom bound to three hydrogen atoms. The carbon atom in a methyl group naturally binds to another carbon atom, in this case one of the carbon atoms in the hexagonal ring. Hence toluene is also called methyl-benzene.
Closely related to toluene is xylene, another variant of benzene, but one in which two of the hydrogen atoms are replaced by methyl groups. (Hence xylene is also called dimethyl-benzene). If the two methyl groups are bound to adjacent carbon atoms in the ring, the compound is dubbed o-xylene; if the docking sites of the two methyl groups are separated from each other by two steps, then the result is dubbed m-xylene; and if the docking sites are on opposite sides of the ring, the compound is called p-xylene.
Most teams seem to have settled on the use of toluene and xylene. By mid-season 1987, for example, Honda “reached an 84% level of toluene,” (Ian Bamsey, McLaren Honda Turbo – A Technical Appraisal, p32).
With respect to the Cosworth turbo used by Benetton in 1987, Pat Symonds recalls that “the problem was the engine had been developed around BP fuel, and we had a Mobil contract. Fuels then weren’t petrol, they were a chemical mix of benzene, toluene and xylene. We kept detonating pistons, and it wasn’t until mid-season that we got it right,” (Lunch with Pat Symonds, MotorsportMagazine, September 2012). In fact, Pat attests that the Cosworth fuel was an equal mix of benzene, toluene and xylene, (private communication).
At Ferrari, AGIP later recalled that their toluene and xylene based fuel reached density values of up to 0.85, in some contrast with the paraffinic fuels of the subsequent normally-aspirated era, with density values of 0.71 or 0.73. “Given the ignition delays of heavy products, we had to add more volatile components that would facilitate that ignition,” (Luciano Nicastro, Head of R&D at AGIP Petroli, ‘Ferrari Formula 1 Annual 1990’, Enrico Benzing, p185).
Renault, in contrast, claim to have used mesitylene, as Elf’s Jean-Claude Fayard explains:
“We found a new family of hydrocarbons which…contained a strong proportion of mesitylene [trimethyl-benzene] and they had a boiling point of 150C, but with a combustion capability even higher than that of toluene,” (Alpine and Renault, Roy Smith, p142).
Mesitylene is a variant of benzene in which three methyl groups are docked at equal intervals around the hexagonal carbon ring, (naturally, mesitylene is also called trimethyl-benzene).
Now, the fact that Paul Rosche grabbed a barrel of aviation fuel used by the Luftwaffe is significant because German WWII aviation fuel differed substantially from that used by the allies. Faced with limited access to crude oil, and a poorly developed refining industry, the Germans developed war-time aviation fuels with a high aromatic content.
Courtesy of the alkylation process, the original version of which was developed by BP in 1936, the allies could synthesise iso-octane from a reaction involving shorter-chain paraffins, such as iso-butane, and olefins such as butene or iso-butene. By definition, iso-octane has an octane rating of 100, defining the standard for detonation-resistance. Using 100-octane fuel synthesised by the alkylation process, the British were able to defeat the Luftwaffe in the 1940 Battle of Britain.
In contrast, German aviation fuel was largely obtained from coal by applying hydrogenation processes. With limited capacity to produce paraffinic components, the initial B-4 grade of aviation fuel used by the Germans had an octane range of only 87-89, a level which itself was only obtained with the addition of the anti-detonation agent, Lead Tetra-Ethyl. A superior C-3 specification of aviation fuel was subsequently produced, with an octane rating of 95-97, but only by substantially increasing the proportion of aromatic hydrocarbons:
“The B-4 grade…contained normally 10 to 15 percent volume aromatics, 45 percent volume naphthenes, and the remainder paraffins…The C-3 grade was a mixture of 10 to 15 percent volume of synthetic isoparaffins (alkylates and isooctanes)…[and] not more than 45 percent volume aromatics,” (US Navy, Technical Report No. 145-45. Manufacture of Aviation Gasoline in Germany, Composition and Specifications).
The Germans, however, also included some interesting additives:
“The Bf 109E-8’s DB601N engine used the GM-1 nitrous oxide injection system…Injected into the supercharger inlet, the gas provided additional oxygen for combustion at high altitude and acted as an anti-detonant, cooling the air-fuel mixture,” (‘The Decisive Duel: Spitfire vs 109’, David Isby).
“Additional power came from water-methanol and nitrous-oxide injection,” (‘To Command the Sky: The Battle for Air Superiority over Germany, 1942-44‘, Stephen L.McFarland and Wesley Phillips, p58).
At which point, one might recall Charlie Whiting’s suggestion that the 1983 BMW fuel brew “had far more exciting things in it”than toluene. This, despite regulations which explicitly stated that fuel should be 97% hydrocarbons, and should not contain “alcohols, nitrocompounds or other power boosting additives.” Still, there’s breaking the rules, and then there’s getting caught breaking the rules. Perhaps BMW were a little naughty in 1983, before settling down with an 80% toluene brew.
The current turbo regulations, however, require a much lower aromatic content, stipulating the following maxima:
Aromatics wt% 40 Olefins wt% 17 Total di-olefins wt% 1.0 Total styrene and alkyl derivatives wt% 1.0
Which entails, in a curious twist, that the current maximum aromatic content almost matches that of the C-3 aviation fuel developed in war-time Germany…
However, there may be hope on the horizon for the minions of Aldermaston, for the aerial photograph provided by the BBC clearly indicates that the former RAF Aldermaston airfield is the perfect location for a Grand Prix circuit.
The prospective layout sketched above suggests a mix of slow-speed 90-degree corners and long-straights, with a high braking and traction requirement. Particularly exciting is the long main straight, which resembles that at Macau, including a flat-out kink leading onto a long, wide stretch which eventually funnels into the heavy-braking area for a tight hairpin. Rather like Turn 1 at the Cleveland airport circuit in the USA, this would, no doubt, become a key overtaking spot.
One imagines wisps of tyre-smoke mixing with the gaseous tritium discharges, as the drivers battle it out, wheel-to-wheel. Happily, with the lower noise emissions of contemporary Formula 1, there seems little chance of triggering an unexpected criticality in one of the facilities, but in such an event the odd blue flash would simply add to the razzmatazz of the event.