1997 BMW M3 Cabriolet
BMW M upgraded the engine in the M3 following the release of the ‘3.2’ at the 1995 Frankfurt Motor Show. Many of the changes to the engine reflect the lessons learnt creating the V12 for the McLaren supercar which was essentially two S50 engines forming a V. The new engine, called S50 B32, was larger and featured the Double VANOS system. This system made both the intake and exhaust camshafts continuously variable. Small changes to the S50 included a second oil pump, larger inlet valves, graphite-coated conrods, lightweight pistons and a new BMW/Siemens MSS50 engine management system.
Attached to the new engine was a Getrag six-speed manual transmission. In 1997, BMW Europe added a Sequential M Gearbox (SMG) as a option which was quite a substantial technology for the period. The system used an electronic clutch and hydraulic cylinders to automatically engage each gear. Following a push or pull on the gear lever the SMG system could change gears in as little as 0.4 seconds.
In Detail
| price $ | $ 40,000 |
| engine | S50 B30 Inline-6 |
| position | front Longitudinal |
| aspiration | Natural |
| valvetrain | DOHC, 4 Valves per Cyl w/VANOS Variable Timing |
| fuel feed | Sequential Electronic Fuel Injection |
| displacement | 3201 cc / 195.3 in³ |
| bore | 86.4 mm / 3.4 in |
| stroke | 91 mm / 3.58 in |
| compression | 11.3:1 |
| power | 236 kw / 316.5 bhp @ 7400 rpm |
| specific output | 98.88 bhp per litre |
| bhp/weight | 218.13 bhp per tonne |
| torque | 319.97 nm / 236 ft lbs @ 3600 rpm |
| body / frame | Unit Steel |
| driven wheels | RWD w/25% Limited-Slip Differential |
| front tires | 225/45ZR17 |
| rear tires | 245/40ZR17 |
| front brakes | Inner Vented Discs w/ABS, Two Piece Floating Rotors |
| rear brakes | Inner Vented Discs w/ABS |
| front wheels | F 43.2 x 19.0 cm / 17.0 x 7.5 in |
| rear wheels | R 43.2 x 21.6 cm / 17 x 8.5 in |
| steering | M-Tuned Steerin Rack w/Variable Power Assist |
| f suspension | MacPherson Struts wSprings, Dampers Anti-Roll Bar |
| r suspension | Multi-Link Z-Axle wSprings, Dampers Anti-Roll Bar |
| curb weight | 1451 kg / 3200 lbs |
| wheelbase | 2700 mm / 106.3 in |
| front track | 1422 mm / 56 in |
| rear track | 1445 mm / 56.9 in |
| length | 4432 mm / 174.5 in |
| width | 1709 mm / 67.3 in |
| height | 1336 mm / 52.6 in |
| transmission | Getrag 6-Speed Manual |
| gear ratios | 4.23:1, 2.51:1, 1.67:1, 1.23:1, 1.00:1, 0.83:1 |
| final drive | 3.15:1 |
| top speed | ~250 kph / 155.3 mph |
| 0 – 60 mph | ~5.7 seconds |
| 0 – 100 mph | ~13.1 seconds |
