Audi S6 vs BMW Alpina B5

What's the difference?

Most buyers don’t care for sedans these days, but those in the premium market are still spoilt for choice, with new model after new model being launched.

The latest on offer is the new Audi S6, which once again attempts to mix executive style with boy-racer performance.

With its predecessor’s 4.0-litre twin-turbo V8 succeeded by an engine that is 1.1 litres and two cylinders short, does it still serve up enough bang for your back?

Of course, the only way to find out is to put the new S6 sedan to test, so that’s exactly what we did. Read on.

The BMW Alpina B5 Bi-Turbo is not actually a BMW. Not according to the German Federal Motor Transport Authority, at least.

Nope, the modifications applied by tuning house Alpina to the 5 Series are deemed so significant that if you open the bonnet and look inside the engine bay, you'll see that the BMW VIN has been struck through twice and an Alpina vehicle number stamped underneath it. 

The B5 is not the first model to be recognised in this way, either; the German government has recognised Alpina as a seperate car manufacturer since 1983.

The B5 has other ‘B' siblings, too. There's the B3 S Bi-Turbo, which is based on the BMW 3 Series, the B4 S Bi-Turbo (the BMW 4 Series) and the B7 Bi-Turbo (I don't need to tell you what this is based on, right?) which I've reviewed, too.

So just what has Alpina done to this unsuspecting BMW 5 Series? Is it really worth the extra money? How does the B5 compare to an M5? Could it actually be superior? And did they really take the speed limiter off to let it warp-speed to beyond 300km/h?