Guy Martin has driven JCB into the record books for the second time this year after hitting 135.191mph in a Fastrac tractor at Elvington Airfield in York.
The achievement follows JCB’s first Guinness World Record for the fastest tractor at Elvington in June. Called Fastrac One, it reached 103.6mph with Martin – a mechanic, motorbike racer and TV presenter – at the wheel.
A team of JCB engineers in Staffordshire then set about developing Fastrac Two, which was lighter than its predecessor, helping it hit a peak speed of 153.771mph on its way to recording an average of 135.191mph at Elvington.
The record-breaking attempt was overseen by Guinness World Records, who confirmed that the JCB Fastrac completed two runs, in either direction through a speed trap set 1km apart, within the allotted time, to set the 135.191mph record.
“The biggest challenges have included aerodynamics, reducing weight and improving performance – getting a five-tonne tractor to safely reach 150mph, and stop again, is not an easy task, but we’re all so proud to have not only reached these goals, but to have exceeded them,” said Tim Burnhope, JCB’s chief innovation and growth officer.
To achieve a 10 per cent weight saving, the tractor’s bonnet was changed from steel to aluminium; non-structural material was removed from the chassis, while the cab and roll cage mounts would be incorporated into the chassis design.
“This has been a massive undertaking, and I was a very small cog in the machine,” said driver Guy Martin. “It was a proper privilege to be involved, so thank you very much to JCB and its engineering team, who got this tractor absolutely spot-on.” Guy Martin
Similarly, aerodynamic analysis and development conducted by Rob Smedley, ex-Williams head of vehicle performance, and computational fluid dynamics (CFD) used by Williams Advanced Engineering, helped to give Fastrac Two a 10 per cent reduction in drag over Fastrac One. This saw the development of new cab air deflectors, a new rear cover, re-designed radiator covers, new side panels, front bumper and cab roof.
According to JCB, Fastrac Two’s 7.2 litre, 6-cylinder JCB Dieselmax engine received a new turbocharger accompanied by water injection and charge-air cooling through ice tanks, which reduced intake temperatures by 50˚C.
An electrically driven supercharger system was again used, while a revised exhaust manifold is said to have contributed to improved flow. The adoption of an anti-lag system also kept the larger turbocharger delivering its maximum boost pressure while gear changes took place. The result of the powertrain improvements was a peak output of 1,016hp at 3,150rpm, and over 2,500Nm of torque.
Burnhope said: “We still managed to use over 50 per cent of standard Fastrac parts…though tyres were an altogether different challenge. At 1.3m tall and weighing 80kg, and usually rated for 40mph, there was a lot of work to do to prevent them growing and heating up, from high-speed use.
“Modifications to BKT’s tyre design ensured high-speed capability, and repeated rig-testing would validate the Ridemax tyres’ capability at the much higher target speeds required for the World record attempt. The tyres were also equipped with sensors that also monitor heat and vibration in real-time.”
To slow the vehicle down, Burnhope said that Fastrac’s advanced split-type air/hydraulic braking system was uprated with different brake pads and discs whilst using the tractor’s standard callipers.
“We also added a parachute on this version as an extra level of safety. Fortunately, we didn’t need to deploy it as all our engineering calculations meant that Guy Martin could comfortably stop the tractor from speed, after each run.”
The Fastrac story was told in a TV documentary on Channel 4 on November 17, 2019 called ‘The World’s Fastest Tractor.’