The 166 is one of the older Alfa models so it's no surprise to find there are no diesel engines in the line-up - Alfa's performance image meant it traditionally only produced petrol powered cars (although a 2.4-litre diesel was offered on the Continent). The entry-level unit is the 155bhp 2.0-litre Twin Spark which revs freely but needs to be worked hard and struggles when overtaking.
Most buyers will prefer the characterful V6 engines and there are three to choose from starting with the 190bhp 2.5-litre, followed by a 220bhp 3.0-litre version. The top of the range car is the superb 3.2-litre V6 with 240bhp that was introduced on facelifted models from late 2003. This covers the 0-60mph benchmark in an impressive 7.4 seconds. The 2.0-litre and 2.5-litre cars get a five-speed manual gearbox while the more powerful engines have a six-ratio gearbox (from 2003 all cars came with six-speeds).
There's also an optional Sportronic auto.
As you'd expect from an Alfa Romeo the handling is agile and the 166 doesn't feel like a big car. The steering is precise and body roll is minimal - it certainly feels well planted to the ground, even through quick corners. Unlike its rivals from BMW and Mercedes, the Alfa is front wheel drive but it rarely struggles to put it's power down, even in the 3.2-litre model.
The ride can feel harsh on poor surfaces, but facelifted versions have revised suspension which addresses this problem, albeit not completely.