I have a 1.4 corsa 16v sri and i only get approx 20mpg i was thinking of toning it down a bit by changing a few parts like carb, exhaust, airfilter,can you recomend anything that may help to gain extra mpg's
Has the car been serviced recently (properly serviced, not just 'oil and filters')?
Have you checked how many miles you get to a full tank of petrol or are you going by the cars fuel computer?