Been thinking of starting a topic like this for a while. There are many things we can learn from Motorsport, what saves time on the track can save fuel on the open road. Whether it's mechanical, technical or cosmetic, there are many links between cars made for racing, and those designed for effeicncy. Let's start;
Aerodynamics: One of the biggest fuel eaters going. The smaller and lower your car, the faster/more efficient. Consider lowering your cars stance to increase airflow. A front or rear diffuser/spoiler can help deflect air over certain parts of the cars body making it more aerodynamic, but beware a large spoiler can also generate more drag. Car Manufacturers are spending lots of time and money recently on aerodynamics.
Wheels & tyres: in racing, large wide tyres are used for extra traction. On a normal passenger car, a smaller diameter wheel with narrower tyres will have less rolling resistance, and a narrower tyre will also cut through the air better than a wider one. Also, consider a more efficient A rated tyre for economy, they may offer less grip and be noisier at speed so be warned. Aftermarket wheels can be lighter too.
Weight: the power to weight ratio is the best way to compare performance cars, a Veyron might have 1000 HP, but it's extremely heavy. A Caterham R500 has a fraction of the power and weight too, so the 0-60 times are equal, as is the power/weight ratio. Consider removing any unnecessary weight in the car, it will be lighter, faster and more efficient. Car Manufacturers are always developing ways of saving weight, using plastic body panels, spaceframe style chassis parts, perspex windows and even cutting out circles in the glass you don't see behind the doors!
Suspension: As well as lower, in most Motorsports, cars have very rigid suspension, this allows the cars to corner at a higher speed than usual. On the open road, cornering at a higher speed will mean less braking is required and less energy is lost, less fuel will be used to accelerate back out of the corner. Fitting a roll cage will not only make the car safer in a crash, but the cars structure will be more rigid too, meaning less bodyroll. Same with a strutmount.
Engine tweaking: The electronic mapping on your cars ecu controls the engine fueling (amongst other things) consider having your car's electronics altered. A car with increased horsepower will be more efficient too, as less effort is required to accelerate, overtake or go up hills etc. Eco mapping is also very popular, it can increase your cars economy by a fair chunk! Certain aftermarket exhausts can also help the flow of the engine too, as factory fitted items can be restrictive due to noise and pollution regulations.
Gearboxes: With a manual, consider fitting a short shifter, it will increase your cars 0-60 time, but also make acceleration from a stop easier and quicker. Double clutch gearboxes can be remapped too for much faster changes.
Just scratching the surface here. Anybody else, feel free to add thier own ideas/theories
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