The BMW M Coupé and BMW M Roadster are high performance models of the BMW Z3 and Z4 coupés/roadsters produced by BMW M. The first generation was based on the Z3 and was produced between 1998 and 2002. The second generation was based on the Z4 and was produced between 2006 and 2008.
All models were produced in the BMW Spartanburg plant in the United States. Some major components— such as the engine and transmission— were imported from Germany.
The M Coupé E36/8, manufactured from 1998 until 2002, was developed under the leadership of engineer Burkhard Göschel with the intention of adding increased torsional and structural rigidity to the Z3 roadster’s chassis. The development team had a hard time convincing the board of directors to approve the model for production, but it was eventually given the green light as long as it remained cost-effective to produce. To achieve this goal, majority of the body panels had to be shared with the M roadster, thus the doors and everything from the A-pillar forward are interchangeable between the coupé and roadster, as are most interior parts. The Z3 Coupé, which combines the M Coupé’s body with the standard Z3 drivetrain, chassis, and cosmetics, was approved for production at the same time.
Sales were slow as BMW provided almost zero marketing budget to prevent direct sales competition from the more profitable E46 M3. The S54 engine was detuned to 315 hp despite a shorter better flowing exhaust and the car was denied the Getrag S6S-420G 6 speed transmission despite the chassis being built with the necessary mounting points. The differential gearing on the S54 M Coupés was increased from 3.23 to 3.15 to further handicap performance while the E46 M3 paired a 3.63 final drive to same powertrain. Gearing on the ZF and Getrag boxes is the same for the 1st-5th gears, but the Getrag adds the .83 overdrive. As a result of their relative rarity, M Coupés (especially S54 powered models) retain much of their value. The M Coupé powered by the S54 engine is one of the lowest production BMWs with only 1,112 built in total for all markets. The Z3 Coupé was given the nickname “clown shoe” because of its distinctive styling.
The M Coupe and M Roadster were initially powered by the engines from the E36 M3. This means that most countries initially used the 3.2 L version of the BMW S50 engine, while North American models initially used the less powerful BMW S52 engine. The S50 is rated at 236 kW (316 hp) at 7,400 rpm and 350 N⋅m (260 lb⋅ft) at 3,250rpm, while the S52 engine is rated at 179 kW (240 hp) at 6,000rpm and 320 N⋅m (240 lb⋅ft) at 3,800rpm. A total of 2,999 cars were built with the S50 engine and 2,180 cars were built with the S52 engine.
Starting in February 2001, the engines were upgraded to the BMW S54 engine from the E46 M3. In most countries, it is rated at 239 kW (321 hp) at 7,400 rpm and 354 N⋅m (261 lb⋅ft) at 4,900 rpm, while North American models have 235 kW (315 bhp) at 7,400 rpm and 341 N⋅m (252 lb⋅ft) at 4,900 rpm. The difference in peak power and torque is due to the catalytic converters being located closer to the engine on the North American spec cars, which allows the catalysts to heat up faster and reduce cold start emissions. 678 M Coupes were made for the American market, with a total of 1,112 M Coupes built with the S54 engine worldwide.
The gearbox is a ZF Type C 5-speed manual. The final drive is either 3.23:1 (S52) or 3.15:1 (S50 and S54). A limited slip differential with a maximum locking of 25 percent is standard.
Like all Z3 models, the M Coupe and M Roadster’s suspension is made up of MacPherson struts in the front and semi-trailing arms in the rear. Compared to the six-cylinder Z3 roadster, however, the M roadster included modifications such as wider front and rear tracks (by 0.4 in (10.2 mm)), reduced ride height (by 1.1 in (27.9 mm)), modified front suspension geometry, firmer springs and shocks, thicker anti-roll bars, stronger semi-trailing arms and a reinforced subframe.
When the M roadster switched to the S54 engine (2/01 production), the chassis was upgraded to the stiffer springs and shocks developed for the M Coupé.
| built at | Munich, Germany |
| price $ | $41 800 USD |
| engine | Inline-6 |
| valvetrain | DOHC 4 Valves / Cyl |
| displacement | 3152 cc / 192.3 in³ |
| bore | 86.4 mm / 3.4 in |
| stroke | 89.6 mm / 3.53 in |
| compression | 10.5:1 |
| power | 178.9 kw / 239.9 bhp @ 6000 rpm |
| specific output | 76.11 bhp per litre |
| bhp/weight | bhp per tonne |
| torque | 319.9 nm / 235.9 ft lbs @ 3800 rpm |
| redline | 6800 rpm |
| body / frame | Unit Steel |
| driven wheels | Front Engine / RWD |
| front tires | F 225/45ZR-17 |
| rear tires | R 245/40ZR-17 |
| front brakes | Vented Discs w/ Vacuum Assist & ABS |
| f brake size | x 315 mm / x 12.4 in |
| rear brakes | Vented Discs w/ Vacuum Assist & ABS |
| r brake size | x 312 mm / x 12.3 in |
| front wheels | F 43.2 x 19.1 cm / 17.0 x 7.5 in |
| rear wheels | R 43.2 x 22.9 cm / 17.0 x 9.0 in |
| steering | Rack & Pinion w/ Power Assist |
| curb weight | 1356 kg / 2989 lbs |
| wheelbase | 2459 mm / 96.8 in |
| front track | 1422 mm / 56.0 in |
| rear track | 1491 mm / 58.7 in |
| length | 4026 mm / 158.5 in |
| width | 1740 mm / 68.5 in |
| height | 1280 mm / 50.4 in |
| transmission | 5-Speed Manual |
| gear ratios | 4.21:1, 2.49:1, 1.66:1, 1.24:1, 1.00:1, :1 |
| final drive | 3.23:1 |
| top speed | ~220.5 kph / 137.0 mph |
| 0 – 60 mph | ~5.5 seconds |
| 0 – 100 mph | ~14.5 second |
