New Cars: BMW M3

Taking over as top-line model in BMW’s admirable 3-series range of small cars is a new homologation special, the M3. Borrowing the M for Motorsport designation which we saw first on the M1, the mid-engined supercar, and more recently on the M5 and M635CSi using the same engine, the new car is aimed at Group A racing, requiring a minimum of 5,000 to be built.

It is always hard to reconcile track attributes with useable road performance, especially as regards the engine, but with an ever-increasing interest in sporting performance and a clientele which is presumable increasingly skilled, it is now possible to boast about the sort of ride once considered rather hard. But nevertheless the Bavarian company has managed to produce a vehicle which feels good on the road and terrific on the track.

Instead of the six-cylinder 3.5-litre M1 engine, BMW Motorsport GmbH, whose project this is, has gone for a 2.3-litre four with a 4-valves per cylinder layout which is very close to that of the bigger M power unit. 200 bhp without catalytic converter is available, and the extra performance is made obvious externally by quattro-style flares over the wheel arches, which are consequently able to cover up to 10-inch rubber for competition, new side-sills, bigger front and rear air dams, and rnost radical of all, a new high boot with flatter rear window line. Other equipment includes well-behaved power-steering of higher ratio than the rest of the range, a closer-ratio five-speed gearbox, limited-slip differential, and ABS antilock braking fitted to larger discs with reinforced calipers.

This is the first BMW model to be developed by the Motorsport department and assembled on the main production lines. A four-cylinder design was chosen because, says the firm, this affords better low-speed torque, and better resistance to high revs because of the shorter and stiffer crank. The aim is to have 300 bhp available when the car goes racing, and the alloy block with its twin-chain-driven cams will achieve this as much through resetting the Bosch Motronic injection system as through any mechanical changes under the very strict (though often cleverly twisted) Group A rules. The same electronics allow simple adjustment to cope with the catalytic converter which German laws increasingly promote.

Without smog equipment, the claimed 0-60 mph figure is an impressive 6.7 sec, with a rnaximum of 146 mph. First gear is back and left, leaving the racing ratios in a compact square layout;  to withstand the high stresses, the lining of the clutch is bonded as well as rivetted to its carrier. Lower suspension with larger front wheel bearing and thicker relocated anti-roll bars and twin-tube dampers have been devised though otherwise the basic layout of the rear axle is as on the standard models in the 3-series range. 15 in alloy wheels with 205/55 VR15 tyres are standard on road versions; the arch flares are of steel, but the new boot-lid is of plastic, while both front and rear screens are bonded to the shell for greater stiffness. Inside, there is not a great deal of difference to be seen, except that the fuel-consumption gauge has been replaced, very sensibly, by an oil-temperature dial. Build quality is of course up to normal standards, and apart from the stiff ride, there would be little to tell the driver he is in an M3 and not a 325i until the road ahead becomes empty. Not the easiest car in traffic, due to a less than slick gearchange, at least on the test cars I drove, and something of a lack of torque below 3-1/2 to 4,000 revs, the M3 gets up and flies when the tach needle reaches the relevant quarter. It displays a lovely snarl which reverberated off the hill-sides of the twisty Tuscan roads we were guided along, on which the steering felt very crisp, indeed almost unassisted, at speed. Chassis balance is excellent, and as we later were able to discover on the Mugello race track, the M3 changes very smoothly to oversteer and adopts a very progressive attitude of slide.

Brakes are almost always the downfall of a road car being driven on a racetrack, but the M3 showed no sign at all of fade or overheating, pulling the car up square and sure repeatedly. With only production car levels of noise, good sport seats, an acceptable ride, and room for four people, plus race-car handling, performance and brakes, this “special” is going to sell on its obvious exclusivity to the sporting driver, even if he has a family, as well as to private teams seeking Group A honours. BMW (GB) do not plan to import the car; any private (lhd) imports will cost around £20,000. But then it is virtually a racing car which can comfortably be driven on the road, and there are not many of those available. — G.C.