1973 24 Hours of Le Mans

In the second year of the new regulations, there were no changes. This year the Automobile Club de l'Ouest (ACO) extended the eligible classes to eight with an extra one each in Group 5 and 2. Reserves were not kept, rather the ACO selected the 55 starters from those who arrived taking into account the results of the Four-Hour race at the Test Weekend. 1973 was the 50th anniversary of the first race and there was much pomp and celebration. Included in this were races for pre-war and post-war cars and the first parade of historic Le Mans competitors. The French Post Office issued a special commemorative stamp. ==Entries==

The ACO received 112 applications. Even though Autodelta, the Alfa Romeo works team withdrew just days before the event there were 61 cars present for practice on race-week. With Sports-prototypes from Matra, Ferrari, Mirage and Ligier as well as Ford and BMW in Group 2, there were 22 ‘works’ entries. and the car now ran on 13” tyres instead of the former 15”. Adding two cars to their regular Championship team made a strong 4-car challenge in an all-French driver line-up. Jean-Pierre Beltoise and François Cevert were constantly quickest but pushed their car hard, whereas Henri Pescarolo/Gérard Larrousse drove with endurance in mind, having got both of Matras victories to date. A third 670B was prepared for Jean-Pierre Jabouille/Jean-Pierre Jaussaud while Patrick Depailler/Bob Wollek had an older MS670. After a dominant 1972 sportscar season, Ferrari was having a much tougher time this year with running in two World Championships, neglecting F1 by entering only one car and skipping some GP altogether. Having come from the latest round with a 1–2 victory at the Nürburgring, and with the championship carefully balanced, the works team arrived in force with now proven reliability. The latest iteration of the 312PB was wider and longer to take bigger tyres and improve handling. The aerodynamic longtail chassis increased speed on Le Mans’ big straights while the improved V12 was now capable of 460 bhp in race-trim. The regular team driver pairings of Jacky Ickx/Brian Redman (who had both Ferrari victories this year) and Arturo Merzario/Carlos Pace were augmented by Carlos Reutemann/Tim Schenken. After 1971 John Wyer had retired from racing as the Porsche 917 sportscar class was discontinued. However, he resumed Mirage M3 plans for his own Cosworth-powered car-design and again convinced Gulf Oil to back the project. Former Ford engineer Len Bailey designed the Mirage M6 based around the Cosworth DFV engine, as he did in 1968 with the disappointing Ford P68. However, the DFV engine was renowned for vibration and being hard on components so a V12 engine, like in the Mirage M2 BRM, was commissioned from Weslake for a new coupé. But continual unreliability meant the Weslake project was shelved and the team focused on improving the V8 spyder refitted with ZF gearboxes, buoyed by a 1-2 result at Spa. Their drivers were Derek Bell/Howden Ganley and Mike Hailwood/John Watson (nursing a broken leg Lola did return to Le Mans after a promising, but tragic, race the previous year. The Scuderia Filipinetti had taken over Jo Bonnier’s team after his death. Despite the Swiss team’s owner Georges Filipinetti dying in May from a heart attack, a car was entered for Jean-Louis Lafosse and Hughes de Fierlandt. An ex-Bonnier Lola was also run by former hill-climb champion Daniel Rouveyran. Alain de Cadenet also returned to Le Mans after a strong run the previous year in his Duckhams-Cosworth, paired again with Chris Craft. The body was redesigned to be more aerodynamic although no high-speed testing had been able to be done. Ligier finally had the improved Citroen-Maserati V6 engine, now capable of 330 bhp and three cars were entered for the race, including one for Guy Ligier himself, with Jacques Laffite. Perhaps the most interesting entry was the first Japanese car to race at Le Mans, and with the first Japanese drivers. Shin Kato’s Sigma Automotive was entered to the race with the MC73, powered by a Mazda Wankel twin-rotary engine. With a claimed performance of 260 bhp it was calculated as a 2292cc equivalent. Three were built for the Japanese series and one came to Le Mans. Porsche could have entered any of its old underpowered low drag Porsche 908 versions again, but these had to carry ballast now as minimum weight had been increased for 1972, thus only privateers raced 908s after 1971, with Joest finishing 3rd in 1972. Filling out the Group 5 field were four older Porsche 908s, including the regular entries from the Spanish Escuderia Montjuïch and Swiss André Wicky. The Carrera RS was lightened, with a big rear spoiler and flared wheel-arches to take wider 11” tyres. The engine had been bored out to 2.7-litres, and now produced 240 bhp. The RSR-variant had a bigger 2.8-litre engine good for 300 bhp. As in 1971, Porsche factory entered as a Martini International sponsored team, now led by David Yorke (former team manager at Gulf-Wyer) and with two experimental versions capable of 320 bhp in the Sports category. In Group 2, the European Touring Car Championship (ETCC) was again very popular with top drivers and close racing, and the mighty battle between the works teams of BMW and Ford spilled over into Le Mans. Ford Germany arrived with three 3-litre V6 Ford Capri for drivers Dieter Glemser/John Fitzpatrick, Gerry Birrell/Hans Heyer and Helmut Koinigg/Jean Vinatier. In response, BMW turned up with the 3.0 CSL run by its newly set up BMW Motorsport works team under Jochen Neerpasch (formerly at Ford). The car had a more powerful inline-6 M49 with 360 bhp over the Capri's 300 bhp. ==Practice==

At the March test weekend, Beltoise put in a time for the Matra four seconds faster than Ferrari had 12 months earlier. Ferrari, citing labour strikes in Italy, did not attend. But Merzario and Ickx immediately set the pace on Wednesday night when official practice started. The smaller teams had a far tougher time. Both the Duckhams and the Ligiers were suffering from unstable aerodynamics. The Duckhams was running over ten seconds slower than it had the previous year. In the small-engine class, the Spanish Chevron was 13th (4:11.0) just ahead of the Sigma rotary (4:11.1). The Porsche RSR prototypes were slower than their test weekend times, until van Lennep found performance improved with narrower rear tyres. Müller recorded a 4:14.9 to be 18th on the grid. Several incidents gave the mechanics all-nighter repair jobs: John Watson's Mirage spun in the Porsche curves and the rear section lifted and clouted him on the head; Lola had a tyre blowout rip up the rear bodywork and Ferrari got an urgent call from the factory saying the valve springs were set wrong needing 48 changes per engine. It was close in the Group 2 and 4 categories with only three seconds covering the best Ferraris, Porsches, Fords and BMWs. Quickest was Glemser in the Ford Capri (4:16.0 for 22nd) ahead of Elford's Ferrari. The Corvettes were off the pace with Greenwood's being the best with a 4:19.6. His special-engine car was disqualified by the officials after Don Yenko had had an accident doing illegal road-testing on public roads after a full differential change. His daughter, also in the car, was taken to the hospital for stitches. The Kremer-Porsche caught fire when oil leaked onto the hot exhaust, necessitating a full engine-change, and Walter Brun put the Wicky-BMW into the Armco at the chicane. ==Race==

Start Bright sunshine in race week became dark clouds on Saturday morning, however by 4pm it was sunny again. Honorary starter this year was Sylvain Floirat, President of Matra. From the first lap, Merzario was bolting ahead, sent out as the ‘hare’ to lead the Matras into a race – a role he relished. Matra was now 1-2-3 with Cevert leading from Larrousse and Wollek, chased by Reutemann in the Ferrari. While the Matras were all running at the same speed, the Ferraris had a variety of strategies. Carlos Reutemann and Tim Schenken were running among the Matras. Jacky Ickx and Brian Redman were running with the slowest 3-litre cars, the Lolas and the Alfa Romeo. After four hours, Jaussaud's front tyre blew out while going down the Mulsanne Straight. Ten laps were lost repairing the suspension. Less than an hour later, Beltoise had almost the same thing happen, and his Matra lost eight laps. So at half-time, Ickx was leading Pescarolo by two laps, while 8 laps further back Facetti in the surprising Alfa Romeo was ahead of Merzario and the Martini Porsche. Morning Dawn came with mist and a light drizzle, but cleared to be another sunny day. Coincidentally, a lap later Pescarolo also came in, with brake problems. Toine Hezemans won the European Touring Car Championship for BMW. Later in the summer, “Pesca” and Larrousse came back to Le Mans to be presented with the Legion d’Honneur, France's highest order of merit. Still to date, 1973 was the final time that the Alfa Romeo works team raced at Le Mans. Scuderia Ferrari's factory team would be absent from prototype racing at Le Mans for 50 years until their return and win in 2023. ==Official results==

Finishers Results taken from Quentin Spurring's book, officially licensed by the ACO Class Winners are in Bold text. Did Not Finish Did Not Start Class Winners • Note: setting a new class distance record. Index of Thermal Efficiency For Group 2 and Group 4 cars. • Note: Only the top ten positions are included in this set of standings. Statistics Taken from Quentin Spurring's book, officially licensed by the ACO • Fastest Lap in practice –A.Merzario, #16 Ferrari 312 PB-73 – 3:37.5secs; • Fastest Lap – F. Cevert, #10 Matra-Simca MS670B – 3:39.6secs; • Winning Distance – • Winner's Average Speed – • Attendance – ? International Championship for Makes Standings As calculated after Le Mans, Round 8 of 10 • Note: Only the best 7 of 10 results counted to the final Championship points. The full total earned to date is given in brackets ;Citations ==References==