The case for the defendant, the sweet little 320i, is quite simple. It will rev. Select second gear, push the long-travel throttle into the carpet and watch the rev needle swing all the way round to the number seven. It’s a decent puller, with 148lb ft of torque at 3600rpm and there’s enough of the 150bhp available at the top end to make exercising the rev needle a worthwhile experience. It has to be one of the smoothest, most neatly installed four-cylinder engines ever produced. But then we already knew that because it’s the same Valvetronic unit that was installed in the 1-series last year. In which, incidentally, it was also very good.
But the 320d has so much more muscle (251lb ft, 163bhp), making a case for the petrol engine is difficult in the extreme. Even so, I’ll try. Right. It’s um, well it’s not a diesel for a start. And the spec sheet tells me it’s 95kg lighter on the scales. Ah ha.
This matters. Never has there been a sweeter-handling front-engined, rear-drive small saloon than the 320i. If you love nothing more than feeling the integrity, balance and agility of cars, then I can honestly recommend this car over the 320d. That will probably account for less than 50 people in the UK, but it’s a fact all the same. Breaking down what it is about the handling that most impresses is nearly as tricky as the process above.
The steering is bang-on for accuracy – not perfect for feel – but better than anything else in the class. The Michelin Primacy run-flat tyres finally confirm that the Bridgestone RE050s used on the new 5-series were sub-standard, because this car rides beautifully. Not softly, but with a well-damped precision that’s normally the preserve of much more expensive cars.
But perhaps the single thing that clinches the deal is the immense rigidity of the 3-series chassis. In most road cars this is a difficult thing to assess, because most begin to shimmy under similar loads. Not the 3-series: it will thump into hideous lumps and ruts without the shell shaking or the steering column shuddering. What a platform for suspension and ultimately wheel control.
In the cabin
And another thing: although this isn’t particular to the 320i, the 3-series now feels fine without several thousand pounds-worth of extras bolted on. This is important, because it will hopefully persuade people to stick close to the £22,590 list price of this SE model. Clear instrumentation and expensive materials will doubtless tempt even more people out of their VW Passats and Ford Mondeos than its predecessor managed to. The heater controls are a touch low, but otherwise it’s a good place to work. Being the everyman’s Three, it also makes do without any kind of iDrive, which in my book is a good thing.
BMW is asking an interesting question with this car. The 320d is £1800 more than the 320i. That’s a significant difference, but whichever way you approach it, the diesel car has to win. After three years it’s inconceivable that the petrol car would be worth anything within £2000 of the oil-burner. And the performance gap is widening by the minute: BMW claims that the 320i is just 0.7sec slower to 60mph, but we’ve just clocked a 320d at 8.0sec dead for the 0-60mph sprint, and its advantage really lies in the gears. Subjectively, the diesel feels much faster.
So the 320i moniker is destined to become even rarer than it was on the last-generation Three. It’s been a curious, perpetually altering badge for BMW’s small saloon. Once a four-cylinder, then a six of almost identical capacity, then a 2.2-litre six and now a 1995cc four. Throughout the past two decades its power has barely altered while the car it’s attached to has become heavier and turbodiesels have changed the way we approach the phrase ‘mid-range power’ forever.
For some, the brief thrills available in wringing the neck of a petrol engine, combined with that smidge of added agility from having less mass over the front axle probably make the 320i worth a look over the diesel. But otherwise, the sensible money will go straight into a 320d.