Obviously this ain't one of your typical tuning proposals as the only visible changes on the 2010 BMW Z4 appear to be limited to the beefier 20-inch Hartge alloy wheels and the carbon-fiber front splitters, but it's a start. Scooped by a poster over at the Zpost forums, the lightly tuned bimmer is an unregistered model owned by a BMW / Hartge dealer. For those that would like something more spicy, no need to worry as it's just a matter of time before we start seeing the usual BMW tuning boutiques announcing their Z4 E89 progammes.