Thruxton is known for being hard on tyres, but it is engines that seem to be taking the strain this weekend, with a number of cars suffering in the stifling Hampshire heat.

Polesitter Gordon Shedden starts round 10 with a new powerplant in his Team Halfords Honda Integra after a clutch problem on Saturday. Starting from pole for the first time in his relatively young BTCC career, Shedden will be hoping to score a second win in the series.

There was an engine change overnight also for Team RAC’s Rob Collard, whose MG caught light during Saturday’s qualifying session. Collard ended the session pulled off on the grass with fire extinguisher foam covering his orange machine.

Mark Proctor’s Fast-Tec Motorsport Honda Civic suffered a similar fate, but unable to explain exactly what happened, Proctor has decided not to risk his spare and he will not take part in today’s races.

“It wasn’t down to over-revving or anything on my side of things”, said Proctor. “And we don’t know why it happened. Although we have another engine in the truck, we aren’t comfortable putting it in the car when we don’t know what happened to this one, so unfortunately we are having to load up and head for home.”

Darren Turner also marked his debut BTCC meeting with a blown engine in the second free practice session on Saturday, although the SEAT Sport UK team were able to change it ahead of qualifying.