The Sports Car Club of America’s brand of racing is an institution like no other, but since 1964 its end-of-season National Championship Runoffs – the extravaganza at which the top competitors from its nine regions go head-to-head for prestigious bragging rights, currently in 27 classes – has been both awesome and legendary in its intensity.

As a curious Limey, I went under my own steam to Road Atlanta in the ’80s and, under AUTOSPORT’s local scribe Jonathan Ingram’s tutelage, loved every second. With every passing season I realise it’s too long since I attended with Van Diemen founder Ralph Firman at Mid Ohio in the ’90s. Other than en route to New Zealand, I’ve not been to the USA since 2000, to race in an HSR historic event on Daytona’s 24-hour course, the stage for the 2015 Runoffs, mirroring ’65!

Last weekend the Runoffs returned to California, where the event was inaugurated at the (now defunct) Riverside track. For its 50th anniversary celebration the venue was the magnificently swoopy Laguna Seca, opened in ’57. Monday’s news of a British success there, delightfully for my old friend Ralph’s RFR marque in the F1000 category, made my day.

Based in a modern industrial unit towering over Van Diemen’s long-time home – across the A11 trunk road from Snetterton circuit – Firman’s small concern built its first motorcycled-engined F1000 car in 2009 and has been knocking at the door of Runoffs success. Finally it opened for Colorado’s JR Osborne in the 2015 development car.

An updated chassis – originated by veteran designer David Baldwin – and a switch from Suzuki to Kawasaki engines were the elements of the equation, but Osborne had previous, having won the now-superseded C Sports racing title in 2007, as well as landing a CSR and (smaller engined) DSR double the following year in one of Lee Stohr’s eponymous cars. “JR’s a proper driver, who gave me great feedback,” observed Firman, Emerson Fittipaldi’s first mechanic in Europe.

Prior to the Runoffs onslaught, the hugely experienced Joey Foster tested the new RFR at Donington and noted the step up in performance of the extremely quick lightweight. Osborne led the 15-strong, eight-marque field (which included the Photon of Canadian Jeremy Hill, the two-litre Can-Am racer) throughout.

Two cars were ordered from the US on the strength of it, and two by new agent West Race Cars in Adelaide, Australia, where 3 earlier versions already run alongside the similarly powered US-designed West WX10 sports racers.