BMW Z4 M
The first generation of the BMW Z4 consists of the BMW E85 (roadster version) and BMW E86 (coupe version) sports cars. The E85/E86 generation was produced from 2002 to 2008. The E85/E86 replaced the Z3 and is the third model in the BMW Z Series. Initial models were in the roadster (E85) body style, with the coupé (E86) body style being added in 2006. In February 2009, the BMW Z4 (E89) began production as the successor to the E85/E86.
As per the Z3, the E85/E86 was manufactured solely in Greer, South Carolina. The M model, the Z4 M, is powered by the S54 straight-six engine.
The Z4 M Coupe/Roadster was introduced in 2006 and is powered by the S54 straight-six engine shared with the E46 M3. The S54 was also on the Ward’s 10 Best Engines list for 2001 through 2004.
The engine in the North American Z4 M models are rated at 330 hp (246 kW) at 7,900 rpm, 3 hp less than the North American M3. In other markets, the power output is the same 252 kW (338 hp) as the M3. The engine had BMW double VANOS system and a compression ratio of 11.5:1. The torque generated by the engine amounted to 355 N⋅m (262 lb⋅ft) at 4,500 rpm. The torque was available from 2,500 rpm.
The Z4 M uses hydraulic power steering, unlike the electric power steering used by the rest of the Z4 range. The Roadster used the E46 M3 steering rack, the Coupe the faster M3 CS/CSL rack. Other changes include a wider front track, revised front suspension, wider non-runflat-tires (measuring 225/45 at the front, 255/40 at the rear), and steering geometry. The brakes and the entire rear axle was too from the M3 CS/CSL.
The M coupe’s production began at the Spartanburg BMW plant in Greer on 4 April 2006.