The JCB Dieselmax is a diesel-engine 'Streamliner' car designed for the purpose of breaking the land speed record for a diesel-engine vehicle. The chassis was designed and built by Coventry-based engineering company Visioneering, with engine and gearbox development by Ricardo Consulting Engineers. During the 2006 Bonneville Speed Week and subsequent FIA record runs, the car was driven by Wing Commander Andy Green, a serving RAF Officer who previously broke the absolute land speed record in the ThrustSSC
.The car began shakedown testing on July 20th 2006 on the runway at RAF Wittering, with the team slowly ramping up the speed to prove the chassis and engines, eventually acheiving a speed of over 200mph on July 30th. On August 13th, after several days spent re-assembling and re-testing the car at Wendover, the Dieselmax made its first official run on the Bonneville Salt as part of Speed Week, eventually attaining an average speed of 317mph to take the SCTA-BNI event record for an 'AA/DS' Diesel Streamliner.
On 22nd August 2006, the JCB Dieselmax car broke the official FIA diesel engine land speed record, attaining a speed of 328.767mph (529km/h). 24 hours later, the JCB Dieselmax car broke its own record, achieving a speed of 350.092mph (563.418km/h) on 23rd August 2006. Before the JCB Dieselmax records, the diesel land speed record was 236mph (380km/h), set in August 1973.
In a live interview from Utah on BBC News 24, Andy Green said that the car was not running at its full potential, due to problems finding suitable tyres and that this speed was achieved while the car was still in fifth gear (the car has six).