through the 1950s and into the 1960s if you wanted to win a saloon car race overall on British soil in effect you had to drive a Jaguar, what broke the Jag winning streak? A Galaxie 500. Strange isn't it?

In 1961 Dan Gurney put Jag on notice by bringing to Silverstone a Chevy Impala. The writing was on the wall as he outran all the Jaguars, piling on the horsepower down the straights and teetering his heeling, tyre-squealing ‘Yank Tank’ on a fine knife-edge round the corners.

He seemed to have the race won, when one of the Chevy’s pressed-steel wheels pulled off over its studs. The Jaguar brigade heaved a sigh of relief, and won yet again – dominance sustained for another year.

In 1962 John Willment and Jeff Urenmade plans for a NASCAR-prepped stock car with sufficient muscle to put the medium-capacity Jaguars very firmly in their place – which would be second, not first.

Working together with Holman and Moody they imported one car in the spring of  1963 and at Silverstone in May, veteran touring car driver Jack Sears whipped the Jaguars. He repeated the trick in June and in July led a 1-2 Ford finish in a preliminary race to the British Grand Prix.

As always when faced with the overwhelming defeat and no hope of competing, Jaguar went for the rules book, and challenged everything about the Galaxie, from roll cage to countersunk lug holes in the rims.

Jaguar's general manager ‘Lofty’ England did his best to get the Royal Automobile Club governing body and race scrutineers to make a great fuss over the Galaxie’s roll-cage, and the design of the pressed-steel wheels on the monster car, with their counter-bored fixing holes. Holman and Moody waded into that one with evidence of FIA-conformity homologation.

Regardless the Willment Galaxie was withdrawn from the Brands Hatch Six Hours, causing disappointment (to say the least) to the entrants, drivers, organizers and – last but not least – the paying public.

https://www.goodwood.com/grrc/columnists/doug-nye/2017/7/doug-nye-jack-sears-galaxie