As you may have read already, the DFV had more than a staring role in the history of Formula 1. A reputation like that though, attracts attention and many others believed they had the perfect use for the V8 in other forms of motorsport. These are their stories.
Right from its initial release to the public, the DFV seemed like the ideal solution for many constructors needing an engine for their sportscars. The top class for endurance racing at the time was Group 6, occupying the prototype endurance racers. Meanwhile, limited-production sports and GT cars were housed in Group 4. By the time the DFV appeared, a 3L engine size limit had been written into the Group 6 rulebook. It appeared the timing couldn’t be better.
Ford Europe took it upon themselves to lead the way in this new class. The rules restructuring had rendered their monstrous 7 litre Mk.II and Mk.IV GT40s obsolete. Meanwhile, the 4.9L Mk.I version was still suitable for Group 4 GT racing duties, now in privateer hands. This led their Ford America counterpart to withdraw from the sport, crucially taking their financial clout with them.
READ MORE: SPOTLIGHT ON A LEGEND: THE COSWORTH DFV
Collaborating with Alan Mann Racing, the European team produced the beautiful P68 prototype. This coupe was designed to fully exploit the Group 6 rules. The chassis and suspension closely echoed Grand Prix car designs whilst the aluminium body’s low 0.27 drag coefficient allowed a top speed approaching 220mph. All with the DFV placed at its heart. While initial tests raised some concerns its first race suggested it could be a race winner, qualifying 2nd and leading at times before retiring with driveshaft failure.
The Cold Hard Truth
The pretty prototype certainly had potential, but it hid a nasty secret. The slippery body caused chronic instability issues, producing far more downforce on the front axle than the rear. This was fine on compact, low-speed British circuits but terrifying on the high-speed tracks in Europe.
The team stuck at it for 1969, even developing hydraulically-controlled active wings for a spider variant. But the FIA’s ban on high-mount aerofoils soon put pay to that idea. All the while, reliability issues hammered the car. In fact, the P68 failed to finish every event it entered.
Ford weren’t alone in trying their luck with the DFV. In fact, most produced much more competent competitors. However, Ford’s high-profile reliability issues, thanks to rushed development and funding restrictions, had hidden the DFV’s own unsuitability. Most issues were caused by it’s flat-plane crank. It allowed much faster engine responses at the cost of greater vibrations. In a long distance race, this escalated such that the V8 often shook itself apart.
READ MORE: FORMULA 1’S 5 MOST ICONIC ENGINES
Other issues presented themselves too. Running the Cosworth in a closed body prototype of course meant less air passed over the engine. This wasn’t a problem in a conventional sense, water cooling with radiators managed combustion chamber temperatures as usual. Instead, smaller mechanical components in the top of the engine started to overheat during longer races. The timing gear was particularly vulnerable.
In a formula car, the engine would be exposed, allowing passing airflow to offer secondary cooling. The shorter sprint races also reduced heat build up in the first place. For endurance, low drag bodies took priority, trapping heat and weakening smaller high speed components, leading to near-inevitable failure.
Fortune Favours the Brave
1975 marked a turning point for the engine’s track record, and at greatest event in endurance racing; the 24 Hours of Le Mans. Due to the ongoing effects of the 1973 Oil Crisis, a minimum fuel stint length of 20 laps was introduced to bring some focus to fuel economy. The front running Alfa Romeo and Renault-Alpine teams knew their cars couldn’t meet this at a reasonable pace and withdrew, while 1974 winners Matra, with nothing left to prove left sportscars for Formula 1.
This was an opportunity for smaller teams like JWA. Famous for their 1968/9 wins in the Gulf liveried GT40s, they had since become a constructor in their own right with their Mirage prototypes. Given the unique nature of this year’s race JWA prepped their new GR8 for it specifically, focussing on a low drag but highly stable design propelled by the DFV.
Their biggest rivals would be Ligier. Realising they would not be able to homologate their JS2 for the GT classes, they went all out for an overall win, replacing the usual Maserati V6 with a race-ready Cosworth V8 too. For the sake of fuel efficiency, both entries detuned their V8s, dropping the rev limit to 8400 rpm and power down to approximately 380 bhp.
The Gulf Mirages took first blood, converting their 1-2 start from qualifying into a race lead. The Ligiers had to settle for 3rd and 5th, split by a Joest run Porsche 908. The #10 Mirage of Vern Schuppan and Jean-Pierre Jaussaud led the sister #11 car of Jacky Ickx and Derek Bell initially, untill swapping at the first pitstops. From there they pulled away, both putting a 3 lap lead on the 3rd placed Ligier by 9pm. At half distance, 2 of the 3 Ligiers entered had retired, while the #10 Mirage had lost 5 laps to a gearbox change, dropping it to 3rd behind the remaining JS2, the #5 of Jean Louis Lafosse and Guy Chassuell.
From here, things remained fairly static until late race drama. The leading #11 Mirage had 2 unscheduled stops to remedy gearbox and electrical issues resepectively. This cut their advantage to under 2 laps with just 2 hours remaining. The surviving Ligier was ordered to run flat out to the chequered flag, reliability be damned. As the clock struck 4pm though, they hadn’t done enough. The #11 Mirage of Bell and Ickx took victory by a single lap to the Ligier, while the sister Mirage kept 3rd. A remarkable podium sweep for Cosworth.
The sprinter would again succeed at Circuit de la Sarthe under similar circumstances in 1980. Impending rule changes blunted the competition, while torrential race during the early hours dulled the pace. Local hero Jean Rendeau would ultimately succeed, winning a race long game of cat-and-mouse against the much faster Porsche 908/80 of Ickx and Joest in a car of his own design and construction.
Home at Last
As ground effect Group C cars became the premier prototype class, the Cosworth remained popular as it had in F1. However, greater effort was made to make the engine suitable for the role. Known as the DFL, 2 versions were produced. A 3.9L unit catered for the most powerful C1 class, whilst a destroked 3.3L version was aimed at C2. This was the entry point for Group C with reduced costs and stricter fuel allowances on the smaller capacity engines to benefit privateer entries.
Ultimately, the 3.9L DFL still suffered it’s F1 routes, and overall success in the World Sportscar Championship would forever pass it by. Despite the redesign, the flat-plane crankshaft had to be maintained, bringing the familiar high-speed vibrations and concurrent reliability woes with it. Ford had once again tried to lead the way, but their C100 suffered all manner of reliability issues, much akin to its P68 predecessor.
READ MORE: THE TOP 10 MEMES OF THE MONACO GRAND PRIX
The C2 class was a different story. As mentioned earlier, fuel restrictions were enforced throughout the field; the cars limited to 330 litres for a 1000km race. This allowed teams to run 3.3L DFL engines understressed, especially compared to competitors using smaller turbocharged units, as was often the case.
With time, it became the darling of the category. Courage, Eccurie Eccosse and especially Spice found much success, taking 5 Le Mans class wins and 4 class championships between them. The 3.3 DFL was a faithful powerplant right up to C2’s disillusion in the early 90’s. This marked the slow end for the category as a whole, as it was torn apart from within. But that’s a story for another time.
The American Dream
It’s no real surprise our staring hero made a home in the States, but it did so under much more controversial circumstances. By 1975, turbocharging dominated Indycar racing, but time was finally catching up with their venerable Offenhauser engines. The unlimited boost pressure teams subjected their engines to was becoming too much too often for the big 4 cylinder, leaving many to search elsewhere for a more reliable option. One such team was Parnelli.
They had working knowledge of the Cosworth DFV through F1, competing with their VPJ4. So, they decided to prepare an experimental version for Indycar duty. After a thorough re-engineering, including a drop in capacity to 2.65 litres, the Cosworth Turbo was ready for the final round of the 1975 USAC season, taking 5th on debut. Buoyed by this strong result, the team committed to a full season the following year with the new engine.
The project gained momentum and performance throughout 1976, with Parnelli scoring wins at Pocono, Milwaukee and Phoenix to secure 4th in the championship. All this by a totally independent outfit with no support from Cosworth. Keith Duckworth (the “worth” in Cosworth) was famously against turbocharging and thought the whole project folly. It was a pointless endeavour chasing the 850bhp+ needed for Indycar with an engine only initially designed to produce 500bhp.
But the results didn’t lie. In fact the project had become so successful, Parnelli planned to become a distributor of Cosworth engines for Indycar, inviting Duckworth to Pocono for discussions. Seeing the performance of the Parnelli-Cosworth first hand, Duckworth instead poached 2 of the project’s lead engineers. This brought the design back in-house to Cosworth, allowing them to continue development themselves and cut Parnelli out of the equation.
Big backing only enhanced the engine’s potential, now known as the DFX. It became the next must-have powerplant for Indycar, with Penske, Mclaren and the Lightnings of Fletcher Racing joining Parnelli in Cosworth power for 1977. That year marked the first of 12 straight championship titles for the turbocharged V8, while 10 consecutive Indianapolis 500 wins would follow from 1978 onwards.
So there you have it. How one little engine went on to make its mark all across the globe. Thanks for reading, and I hope you enjoyed this jaunt through the archives!
- Chelsea Column: what can we expect from the Blues in 2022?
- Formula 1 2021 Season Review: The greatest title fight ever?
- Top 10 Memes of the 2021 Formula 1 Abu Dhabi Grand Prix
- 2021 Abu Dhabi Grand Prix – FP1 & FP2 report – Hamilton fastest, but games are at play
- F1 2021 Abu Dhabi Grand Prix Preview: Showdown in the desert to decide the title