MOUNTUNE REVIVED RS500
At July’s Silverstone Classic, mountune Racing returned to the scene of its famous victory of Rob Gravett’s Sierra Cosworth RS500 over the Andy Rouse Engineering sister car in the 1990 Grand Prix support race. But there was a twist: this time, mountune was working with the Kaliber sponsored ex-Rouse car, raced by Julian Thomas in the JET Super Touring Car Trophy. That’s right, they’re providing engines for their former rival! But all’s fair in love and racing, and 28 years of technological evolution means that their engines are produced in quite a different way now; whereas the race-spec YBs were at the peak of their operational performance window back in 1990, nowadays it’s more a case of detuning the motor so that it ‘only’ produces 550bhp. With modern management systems and refined camshafts, pistons, rods, and a multilayered steel head gasket, mountune are having to reduce boost pressure to get power down to 1990 levels!
“It’s certainly a strange feeling working with the old rival,” said David Mountain. “Although the Silverstone Classic is a real celebration of historic motor racing so it doesn’t have quite the same pressure we were under in 1990. I remember back then going up and down the bypass on trade plates trying to set the boost up properly. Not sure that would happen today…”