The Z4 M roadster followed the tried and tested route of fitting a powerful engine into a relatively small roadster shell – a modern version of cars like the classic Cobra 289 and Healey 3000 (or any TVR!). In this instance, the 338hp straight 6 engine came from the E46 M3, which also donated most of the suspension components, although the brakes came from the CSL. As well as providing a “halo” variant for the Z4 range, it gave BMW a car to compete with the Porsche Boxster S and Mercedes-Benz SLK55.
Unlike its predecessor the Z3 M, externally there was little to differentiate it visually from the lower specification variants – a deeper front bumper and quad tailpipes, but no enlarged arches and huge wheels. There were some M badges inside and out, of course, plus a chunky steering wheel, but the overall effect was much more subtle. Mechanically, apart from the M3 engine and suspension, the big change was a switch from electric to hydraulic power steering, and it was only available with a manual gearbox.
The E85 Z4 M was only produced for a couple of years – 2006 to 2008 – and like most M cars was only really offered in one level of specification, so when looking to buy a used example the main factors will be colour and possibly options such as navigation. Owners tend to be enthusiasts so most used examples have been well looked after and are usually relatively low mileage for their age. As the car has now become something of a classic, values have started to strengthen of late, reflecting the growth of interest in the more “analogue” sports cars. Asking prices tend to be influenced by mileage and currently range from £13,000 to £20,000, although as usual with cars of this type there are always a few priced on the stronger side. Provided it has been properly maintained (and has a service history confirming this) there is no reason to fear a higher mileage example, and as long as it continues to be looked after it is unlikely to depreciate much, if at all, over the next few years.