Petrol Vs Diesel Engines – Which Is Better and Why? Part II

It is a known fact that diesel’s best selling point is its efficiency. And while petrol hybrid cars are very efficient, they still can’t match the fuel economy of diesel hybrids. The scepticism that however still remains attached to diesel-powered cars is that they are slow, but with the introduction of the turbocharger, engineers are proud to say that that is no longer a problem.

Global warming, rising sea levels, erratic rainfall patterns and increased pollution are some of the factors that have led to a shift by car manufacturers to produce smaller engines with automatic transmission that are tuned for efficiency rather than performance. I mean back in the 70’s, when Chevrolet used to make 7.0L engines called ‘turbo fire’ on manual rear-wheel coupes, who would have imagined that a time would come when a car would come fitted with a CVT on a 900cc engine and this was considered normal? They say that the beautiful ones are yet to be born, but in the motoring world the beautiful (and great) ones were long born. By saying this I wish I had time to delve into the relegation that car design has and will continue to suffer, but let me stick to the debate at hand for now.

Having understood that engines are being reduced in size to address the effects of global warming, turbochargers, which vary in size and operation, have been employed to give diesel engines the speed of their petrol counterparts while retaining their superb efficiency. Almost every pick-up truck and SUV diesel engine coming off the production run right now is turbocharged, but reduced in size so that the same output of a 4.0L engine can now be achieved by a 2.5L turbo diesel. The result is a combination of massive power and great fuel economy, which is a win-win for both the consumer and the environment.

European car manufacturers have proven that diesel-powered cars can be faster, quieter and cleaner than petrol-powered ones, and that is why half of the new cars from Europe are running on diesel. But even then, a diesel engine will still demand more attention than a petrol one, and of course, turbo or no, petrol will still burn faster. And you can also make a ground-moving aircraft off a car by installing a supercharger on a petrol engine, that’s why sports cars will never run on diesel. But how many people are buying new sports cars anyway? Look at the trend: the World Car of the Year in 2008 was Mazda Demio, in 2009 it was the Volkswagen Golf, in 2010 the Volkswagen Polo, in 2011 Nissan leaf took the crown, 2012’s winner was Volkswagen Up, in 2013 it was the Volkswagen Golf again and in 2014 it was Audi A3: people now want small, convenient shopping cars that take up less parking space, don’t burn the pockets at the filling station and are easy to manoeuvre in tight city spaces. Of all these cars, Nissan Leaf and Volkswagen Up are the only ones that don’t run on diesel, with the Leaf being electric, which leaves the Volkswagen Up as the only petrol purist. Is it therefore true to say that diesel has beaten petrol? I would say yes.