Ever heard of a little roadster called the BMW Z4? It's got a retractable metal top, all the creature comfort you could want and comes with the same award-winning engine as the 335i. Yet, somehow the Bavarians managed to get it wrong, as it never managed to capture our imagination as easily as the 1-Series M Coupe did.

That's where we introduce our honored guests, the German tuning experts from Kelleners Sport, who set their attentions onto the most powerful and sporty version -the BMW Z4[...]

Source: autoevolution