As someone who is usually less than impressed with government legislation, I find it surprising how often new regulations have succeeded in forcing the automotive industry to significantly up its game.

Back in the early 1970s, California’s revolutionary 'clean air' act forced car makers, selling into this all-important market, to dramatically reduce the pollution emitted by their engines. The heavy-metal merchants from Detroit chomped on their collective cigars, while declaring the requirements impossible to meet without extensive ‘de-smogging’ kit and much reduced power. 

Then Honda came along with the CVCC (compound vortex controlled combustion) engine, which could meet the regulations without a catalytic convertor. This made Detroit look pretty stupid and forced the rest of the industry back to the lab, to the benefit of the environment.

Current EU legislation has forced car makers to improve average fuel economy, while the increasingly stringent pollution regulations will make future-generation diesel engines significantly more expensive to build. This has also led to an unexpected - and most welcome - leap forward in petrol engine technology.

Trapped between the demands for better economy and the high-cost of EU6-compliant diesel engines, car makers have finally started to apply some hard thinking to gasoline engineering, after a decade or more of concentrating on oil-burners.

Ford’s 1.0-litre turbo three-pot is an absolute jewel and is already on sale. Personally, I suspect that the new Fiesta equipped with this motor will become something of a landmark car. However, I’ve also had the privilege of driving an as-yet unreleased three-cylinder engine that could become a crucial ingredient in serious driver’s cars.

It’s no secret that BMW has been developing 1.5-litre, three-cylinder, turbocharged petrol and diesel engines. The B38 and B37 units will be the mainstay engines for the Mk3 Mini and BMW’s upcoming family of compact front-drive cars. However, the new alloy-block motor has also been designed to be longitudinally mounted, making a racing certainty for future rear-drive BMWs.

At a technical briefing for the new engine, we were led out onto the disused airfield that is now a BMW Experience Centre, and presented with a 1-series fitted with a prototype version of the petrol three-pot. The first thing that struck me was just how small it looked in an engine bay that can accommodate a straight-six motor.

But the upside is that the three-pot sits right back in the engine bay, offering the kind of weight distribution that few front-engined production cars could hope to match. I had a quick spin around the test track in the 1-series and a few things became crystal clear.

First up, this engine was very punchy and sporty (they wouldn’t tell us the output, but I’d guess around 150bhp) and gratifyingly quick to rev. Smaller engines with lightweight, downsized, internal components are a delight.

Second, the balance and cornering prowess of the 1-series was on a different level, as you might expect when the weight in the nose has not only been reduced, but pushed as far back as technically possible. Of course, a lighter nose means the car's steering - even on a prototype - is noticeably lighter and sweeter.

These downsized petrol engines are nothing but good news: more frugal, more fun to drive and a significant contributor to driver enjoyment. Can a three-pot M car be far away?