On the race track in particular the G4 with a 1500 engine was very successful, but it was noted that the ability to get the power down on the road with the lightly loaded solid rear axle was a struggle. Chris Meek was winning races with his G4 fitted with a 1500cc engine bored out to 1650cc and he in particular was telling Ivor Walklett how much extra would be gained by fitting an independent rear suspension set up. Ivor was already working on modifying the G4 chassis to IRS for a development of the G6 which was to be known as the G7 and so he adapted that to the Ford engine and gearbox configuration. The independently sprung hub carriers were driven by a cut down BMC axle retaining only the differential unit and to this inboard disc brakes were added. The first G4R was fitted with a Lotus Twin Cam engine to test the capability of the new set up and it made an unplanned debut at Mallory Park in July 1964 with Meek driving. Meek steered it to a first time out win and from then on for the rest of the season he was the unofficial works driver beating most including the competition version of the Lotus Elan and Diva. The model became formally available in September 1964 and proved a race winner for a burgeoning group of young racers at the time, including Johnny Blades, John Burton, Paul Bryan, Malcolm Douglas and David Cameron. The car was run internationally at the Nurburgring and Montlhery in period, while the USA importer took a car and ran it in the 1965 Sebring 12 hour race.