Two wins for BMW in the Dunlop MSA British Touring Car Championship at Oulton Park last weekend, both taken by Northern Irishman Colin Turkington in the eBay Motors 125i M Sport, have swung the pendulum firmly in his direction in the title race.

But it isn’t going to be plain sailing for him to extend his lead from now on. The championship’s rule makers have stepped in after those rounds in Cheshire last weekend and mandated a first gear ratio to be used from now on for all rear-wheel-drive cars. It will affect Turkington and his team-mates Rob Collard and Nick Foster, as well as the Audi A4s of Rob Austin and Hunter Abbott.

The rear-wheel-drive cars have an inherent advantage away from the line. Once the machines begin to accelerate, the weight is thrown to the rear of the car, thus creating more grip over the driven wheels. This means it accelerates faster than a front-wheel-drive car, which is pulling all of its weight through its two foremost two Dunlops.

Any rear-wheel-drive car that qualifies anywhere in the front two rows has a decent sniff of being ahead by the time the pack reaches the opening corner. It is something that the front-wheel-drive brigade have been moaning about for a while, but that advantage will now be gone with the mandated Xtrac gear ratio. For cars that are all built with the same controlled parts, any advantage lost is a painful blow.