Throwback: McLaren’s F1 breakthrough – The M23 Cosworth

James Hunt's championship-winning McLaren M23 Cosworth is driven around Mazda Raceway Laguna Seca during the 2014 Monterey Motorsports Reunion.

In an era when most racing car manufacturers chose to focus on one or two series only, McLaren ran their cars with great success in four major championships: Formula 1, Can-Am, F5000 and Indy. The general conception was that individual campaigns would suffer if a manufacturer ran in multiple championships simultaneously. McLaren, on the other hand, proved them wrong and used the various programs to their advantage. In a period of less than five years, the team won the three of the aforementioned championships and the Indy 500.

In 1973, one of the last hurdles to tackle was winning the Formula 1 World Championship. Although McLaren campaigned in F1 from 1966, it did not fare any better than the odd win. Making the most out of their unique situation, McLaren combined the monocoque of the 1972 Indy 500 winning M16B and the suspension of the M19 F1 racer to create one of the most successful F1 cars ever constructed. Responsible for the overall design was Gordon Coppuck.

Some modifications had to be carried through to convert the M16B for F1 use: The Offenhauser Indy engine needed a sub frame to support the rear suspension. The Cosworth DFV engine, on the other hand, could be used as a fully stressed member with the suspension bolted directly on it. The suspension was modified to suit the road tracks compared to the oval-track the Indy 500 is run on. One of the biggest visible differences was the addition of a large air box to force air into the engine intakes.

Livered in Yardley colors, the M23 made its debut in the third race of the 1973 reason. Denny Hulme promptly qualified it on pole and he did so again in the next race. Seven races into the season, he scored the car’s maiden victory. In the remainder of the year his team mate Peter Revson scored another two victories, which was good enough for McLaren to finish third in the constructor’s championship behind champions Lotus and Tyrrell. Revson and Hulme finished fifth and sixth in the championship.

For 1974, veteran Hulme teamed up with 1972 world champion Emerson Fittipaldi. Outwardly the M23 changed little, except for the new Marlboro-Texaco livery: The start of a long relationship between McLaren and Marlboro. Both drivers proved their worth by both taking a victory in the first two races. Both drivers won two more races and Fittipaldi’s consistency throughout the season earned him enough points to score his second world championship. The team’s performance earned the team its first constructors title. Earlier in the year, a M16C scored the team’s second Indy 500 win.

View 144-shot gallery of the McLaren M23 Cosworth HERE

Hulme retired at the end of the successful season, after a very successful racing career, in which he won multiple Can-Am championships for McLaren and a F1 championship for Brabham. His replacement was Jochen Mass, who had driven a semi-factory backed M23 in the previous season. Fittipaldi scored two victories with the M23, but his performance was no match for Niki Lauda in the brand new Ferrari 312T. At the end of the season he was runner-up in the championship behind the Austrian and McLaren secured a third position in the constructor’s championship.

After James Hunt’s stunning performance in his Hesketh in 1975, the McLaren team hired him to replace Fittipaldi for the 1976 season. The Brazilian left the team to race for his brother’s team. The high air box that had become a common sight on the grid in the previous seasons was banned from the fourth race of season. McLaren created a new air box with intakes on each side of the roll bar, which still fed plenty of air to the DFV engine, but complied with the new regulations. At the beginning of the season there were high expectations of the battle between reigning champion Lauda and the upcoming star Hunt.

Halfway through the season, Niki Lauda seemed ready to clinch his second consecutive title. Eight races into the season he had twice as many points as his closest rivals, after winning four races and scoring another three podium finishes. Hunt was trailing by 26 points after taking two victories and one second place. The season turned around dramatically when Lauda had a near-fatal crash at the Nürburgring. Although he survived, he was badly burned and the season looked over for him. Amazingly, only three races after his horrific accident, he was back in action, his wounds barely healed.

Lauda was back, but he was not able to match his pre-accident pace. Hunt made the most of it, winning four of the six races after the accident. Going into the final race, he was three points adrift of championship leader Lauda. What happened next was without a doubt the most controversial championship deciding race in Formula 1 history: It had rained all day before the start of the Japanese Grand Prix and the driver’s and team-owner’s were unanimous in their decision not to race. The organizers, however, didn’t want to let the 150,000 strong crowd down and decided to start the race regardless of the competitor’s complaints.

Drama through rivalry: The 1976 F1 season in pictures

Luckily for the drivers, the rain seemed to die down slightly right before the start, but the many deep puddles of water on the track remained. Hunt was on pole and reached the first corner in the lead, which gave him the advantage of a clean track without the spray of other cars. Lauda, on the other hand, decided to call it a day, he probably still had the accident on his mind and didn’t want to tempt faith again. With Lauda out of the way, all Hunt needed was a fourth place finish. After a spin and a series of pit stops and with five laps to go, Hunt was in fifth position. Three laps before the end of the season, Hunt secured a third spot and the championship.

Now entering its fifth season of Formula 1 racing, the M23 was clearly showing its age. Halfway through the season it was replaced by the slimmer M26. McLaren had finally followed the competition in concentrating on Formula 1 completely, but ironically the following years were the worst in the company’s history. With 16 victories, two driver’s and one constructor championship under its belt, the M23 remains as one of the most successful Formula 1 racers of the 1970s. Unique is also McLaren’s second ‘double’ in 1976, with the team scoring their third Indy 500.

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