Le Mans Lotus leads 75th anniversary display

In the history of motorsport, where innovation and speed reign supreme, the Lotus 15 emerged as a pivotal chapter in Colin Chapman's pursuit of excellence – and at the Scramble on Sunday 8 October you can see a very special example thanks to Classic Performance Engineering, residents of the Main Stores on the Western Avenue.

Chassis 607’s outing with the works, Team Lotus Engineering, was brief but certainly notable.

In the 1958 24 Hours of Le Mans, with Graham Hill and Cliff Allison down to share the driving duties, the little 2000cc 15 qualified in the thick of the top six behind the 3-litre Aston Martins. Quicker even than recent victors Jaguar and the eventual winners, Ferrari.

Race day lasted only a few laps for 607, with a blown head gasket sending the car steaming out of the contest after three laps.

Fresh from restoration, paint barely dry and final touches being added, 607 will take centre stage at Classic Performance Engineering during the Scramble on Sunday 8 October to lead our tribute to 75 years of the marque. Outside, around 15 other Lotus models will mark the milestone as part of the sprawling ‘Birthday Brits’ theme. (Book tickets here)

The 15 was developed from the groundbreaking Eleven and ushered in a new era of versatility, giving Lotus a racing car that could compete in a wide range of classes. The project was sparked into life thanks to the availability of the Coventry Climax's line of FPF engines, which was initially conceived for Formula Two racing but boasted various displacements from 1.5 to 2.5 litres. Lotus embraced the 2- and 2.2-litre variants, and the stage was set for this automotive marvel to compete in a multitude of racing classes.

One of the defining features of the Lotus 15 was its unique ‘Queer Box’ transaxle. This sequential-shift, five-speed gearbox, nestled alongside a ZF limited-slip differential, provided lightning-fast gear changes reminiscent of a motorcycle transmission. Weighing in at a mere 38.5kg, the transmission was positioned behind the driver for optimal weight distribution. However it earned a mixed reputation, often being referred to as ‘a gearbox full of neutrals’.

Visually, the Lotus 15 bore a striking resemblance to its predecessor, the Eleven, yet its larger radiator opening and low, full-width windscreen were defining features. Series 2 and 3 iterations featured a distinctive bonnet scoop. All Lotus 15s were bodied in aluminium by Williams & Pritchard Ltd., concealing a familiar-looking spaceframe chassis. Notably, the 15 was the first sports racer from Lotus to feature four-wheel independent suspension.

To minimise frontal drag, Lotus experimented with the FPF engine's angle, initially tilting it at around 28° from vertical. However, a swift correction returned it to an angle of approximately 17°, showcasing the brand's commitment to optimising performance.

Inside the Lotus 15, drivers found themselves sitting remarkably low, with minimal padding and a laid-back backrest. The wrap-around windscreen, designed to adhere to racing regulations while minimising air disruption, set new standards. It was all in the name of reducing the scuttle height and enhancing aerodynamics.

The Lotus 15 came in three distinct series. Series 1 introduced the model but faced challenges with the Queer Box. Series 2 saw the introduction of a BMC B-series four-speed transmission, resolving previous gearbox issues. Finally, the Series 3 featured a beefed-up frame, revised front suspension, and updated bodywork, offering a versatile choice of transmissions.

Production of the Lotus 15 concluded in 1959, leaving behind a legacy of 28 cars. Each had been available fully assembled or as kits, used for both new builds and repairs.

Despite some significant victories, the Lotus 15's destiny was shaped by the mid-engined Cooper Monaco, rendering it obsolete at the highest echelons of racing. Lotus shifted its focus to the development of the type 19, a mid-engined sports racer.

In retrospect, the Lotus 15 stands as one of the final front-engine race cars to make a significant impact on the motorsport. Its legacy lives on as a testament to Lotus' commitment to pushing the boundaries of racing technology. The Lotus 15 remains an enduring symbol of innovation and speed in the world of motorsport.

At the October Scramble you can see the actual Lotus 15 raced by Graham Hill, Cliff Allison and Pete Lovely. The car, chassis 607, spent some of its life dirt tracking in Nairobi before returning to the UK where it underwent a recent restoration at Classic Performance Engineering.