Andy Shepherd testing AC 428 Frua "Boris" at Brands Hatch Oct 1989 .
"Watch out, I am still unsure quite how this is all working, but I have found a photo of my first effort to enable "Boris" to survive on a race track. This was back in October 1989 and the plan was to race at the Bentley Drivers Club meeting at Silverstone. The car still had a stock 3 speed auto box, and wire wheels shod with Dunlop M section Racing tyres. You can see the front air dam which made a huge difference to the cooling. Without it, the engine would overheat after 2 laps at over 120C. With the dam, it would run flat out and stay at 90-95C for the entire race. This gave substance to my theory that the bumper and nose split the airflow over and under the car, with little or nothing passing through the radiator. The dam stopped or reduced the flow under the car, and built up pressure at the radiator intake. As there was no air going under the car, the pressure there was reduced, and bingo the high pressure flowed through the radiator, and out under the car! The downside was the look, much like a Datsun 240Z."
(Subsequently converted into fibreglass racing "replica" - "The Black Car".)
ROL SPORTSCAR CHALLENGE Silverstone, 22 March 2003 http://www.raceorganisation.com/scc/2003/silverstone/default.asp "The opening round of the new ROL Sportscar Challenge was won comfortably by pole-sitter Richard Chamberlain in his mighty Porsche 935R. Andy Shepherd, in his carbon-black AC 428 Frua, gave chase and endured a rather more interesting time than was apparent from outside. Having broken the gearshift, searing heat from the exhaust system then began to burn the carbon fibre sills and fill the car with smoke!"
