The Sorrell Kurtis Special GMC inline-6, also known as “Dick Lane’s GMC under Glass” (under glass being a euphemism for the engine located under the fiberglass hood), is an American Special that has not been seen by public for more than 65 years. A few years back John Mote recovered and renovated this astonishing machine which is slated to race at the Rolex Monterey Historic Revival in August 2023.
In 1953, successful Beverly Hills home builder, Dick Lane set out to build the ultimate sports car he could drag and road race. The resulting car was featured twice on the cover and in 6 subsequent issues of Car Craft Magazine starting in 1954. Lane hired the best So. Cal. talent to utilize the latest race technology of the day, including Indianapolis winning chassis builder Frank Kurtis, body designer/ builder Bob Sorrell, and Indy driver and engine builder Frank McGurk.
The Kurtis 500KK chassis (#KK4) featured full torsion bar suspension and was a wider version of the same chassis that won the Indy 500 5 times. Bob Sorrell designed and produced a total of 8 SR-100 bodies. The first car was the aluminum prototype which was constructed on a Kurtis 500KK chassis and shown at the 1953 Petersen Motorama. Sorrell subsequently produced 7 fiberglass bodies that were mounted on a variety of chassis.
For the Lane SR-100, Frank McGurk built a 302 cubic inch GMC inline-6 bored to 320 ci with McGurk pistons, rods, hollow push rods and camshaft and fitted it with a 12 port Wayne-Fisher cross flow aluminum head – just one of 24 produced and stamped “MFG R. Lane 2-54”. Bolted directly to the head’s intake ports were 6 Amal slide carburettors (think Triumph motorcycle) with no manifold. A 12-cylinder distributor with dual coils from Spaulding distributors of Monrovia, California provided spark with manual advance on the dash. The carburetion and ignition systems proved unreliable and although the car would run, no real miles were put on it even after induction was changed to side draft Webers.
Keeping with the Indy theme were Halibrand magnesium center hub knock off wheels and quick-change rear differential. Early technology Lockheed single pot disk brakes were also fitted front and rear.
Mote said. “When the engine was rebuilt, we found assembly grease still present on some of the bearings. Although the car resided in the desert for more than 60 years, very little wear was evident on the engine internals, brakes, and chassis.” For racing reliability Mote fitted a period correct magneto for spark, Stromberg carbs on a custom manifold, drum brakes front and rear, and safety equipment as required, including a roll cage, fire suppression system, fuel cell, and a 5-point harness.
In addition to Dick Lane’s car, at least 2 other fiberglass bodied SR-100 sports cars are known to survive. The aluminum-bodied SR-100 prototype has recently undergone a meticulous restoration and will be shown at the 2023 Pebble Beach Concours d’Elegance where it will be seen by the public for the first time in 70 years.
Mark Tanner asked on Facebook after the 2023 RMMR: “so what’s with six exhaust headers but only five carbs?” John answered 24 August 2023 “When we purchased the car it was fitted with two side draft Webbers , each mounted on an intake manifold serving 3 intake ports. The original Amal carbs we in a spare parts box. Having experience racing Stromberg 97, we decided to use those and had a custom manifold forged to allow for the carb’s velocity stacks to pull fresh air from an opening in the hood , 5 were chosen to have one carb between each intake port but mostly 5 were chosen for aesthetic reasons . The three center 97’s are primary 250 CFM and the two on each end secondary 150 CFM with accelerator pumps removed , they open at 60% throttle”
Written in July 2023 by owner/driver John Mote, further info on the Bob Sorrell cars by Mark Brinker and edited/posted by Marcus Bicknell marcus@bicknell.com on July 23, 2023
Look forward to Mark Brinker’s book on Bob Sorrell coming soon. More about Sorrell now at…
https://kustomrama.com/wiki/Sorrell-Manning_Special
https://www.rcnmag.com/fresh-finds/sorrell-bodied-kurtis-500kk