BMW M3 Compact V-8 Engine

A supercar from BMW! After all the rumours of the new BMW M3 having a big V-8 here it is ? and what a corker! With a very compact, light V-8 engine, producing 420 bhp - 60 bhp more than the excellent six-cylinder engine of the previous model - the new M3 rises to new heights. No more a sporting coupe, now a real supercar capable of hitting 60 mph in 4.7 seconds, but limited to 155 mph.

Not only that, but the guys at the BMW M Center were not having the standard panels of the standard 3 Series, but wanted to make the car looker sleeker, and so here is the best looking BMW for many a year. Sleekness replaces the quirkiness of the current generation. In fact, only the headlamps, doors, windows and trunk lid are common to other 3 Series models, otherwise the car is completely re-skinned.

The M3 remains unmistakably BM, but has a much more sporty look than the standard car, and a practical one at that. At the front, there is a large air intake below the grille, with wide intakes each side, and these change the look of the car. Note that there are no fog/driving lamps cluttering up these intakes, as is common these days on everything from a Porsche down to rather boring pseudo-sporty sedans.

There is also a small hump in the hood to make way for the intake system of the V-8 engine.

Wedge line and flared wheel arches

At the sides are small air vents, and the car has a wedge line, but shaped sills to give it more individuality. The wheel arches are flared, and there is a small spoiler on the trunk lid ? nothing exaggerated as on some sedans. Most of the down force comes from the discreet splitter and diffuser beneath the car. On the other hand, there are two pairs of widely spaced exhaust pipes to hint at the power ahead.

Overall, a super looking job. Oh, yes, and the roof is black lest you should forget that it is carbon fiber, and part of the car's sporty credentials. The carbon fiber reinforced plastic (CFRP) roof replaces the reinforced steel arrangement, saving 11 lb (5.5 kg) in weight, which is not very much, but because the weight is high up, the result is a lower center of gravity, less roll and pitch and better cornering.

4.0-liter V-8 revs to 8,400 rpm engine

Sitting in the engine compartment is this marvelous new and compact 4.0 liter V-8, not the larger and heavier 4.4 liter unit some were expecting. This is from the same family as the 90-degree V-10 used in the M5 and M6, with the same cylinder dimensions and cylinder head design. The engine is designed on the lines of the Grand Prix engines used in the Sauber cars, with the cylinder blocks being cast in the same foundry as the Grand Prix engines.

The new V-8 is very compact, like the V-10, and is actually lighter than the in-line six used in the current M3 ? the new engine weighs 445 lb (202 kg) - 83 lb (38 kg) less than the six. Of course, the V-8 is also a good deal shorter than the in-line six, but wider. That is a lot. It develops 420 hp at 8,300 rpm and 295 lb ft (400 Nm) of torque at 3,900 rpm, but the torque curve is almost flat from 3,500 rpm to 5,000 rpm, promising plenty of power through a large range ? 3,000 ? 8,400 rpm.

Although the specific power output is good at 105 bhp per liter, it is lower than the 110 bhp per liter of the previous six-cylinder engine.

Efficiency is enhanced by the use of regenerative braking ? when you brake or the engine is on the over-run the alternator charges a special battery, saving energy. Normally, the alternator is not driven except on the over-run or when braking, saving energy, and this is definitely something that will become common in the next few years.

No cylinder liners in block

To save weight, the cylinder block is made from high-silicon aluminum alloy so the pistons can run directly in the aluminum without cast iron sleeves. To allow them to run smoothly on the silicon-aluminum, the pistons are coated with iron. This type of block and pistons are used by Mercedes-Benz, but were pioneered by the engine of the Chevrolet Vega.

Like the V-10, the engine has compact combustion chambers with narrow angles between the valves, and double Vanos variable valve timing, giving the car good performance at all speeds. Low-speed response is improved with the use of individual throttle butterflies for each cylinder.

With the trend toward dry sump systems, it is a surprise that BMW has retained a wet sump on the M3, largely because there is not much room left for a dry sump system under the hood. To overcome this limitation, there are two connected sumps ? one in front, and one behind the front cross member. As these are both fairly small, they should hold the oil during fast cornering but two pumps that ensure a good supply of oil.

Incidentally, BMW does not want you to over-rev this engine when the oil is cold ? quite right, too ? so there is an indicator on the rev-counter which shows the revs you can use. This increases as the oil warms up.

To reduce the height of the engine, a two-plate clutch is used, and this drives through to a six-speed manual gearbox ? no news of a seven-speed sequential box as on the M5 and M6 as yet.

Aluminum suspension

Needless to say, all the suspension components are new, even though they are similar to those of the other 3 Series models, but changed to give more responsive handling. At the front, the links are all aluminum forgings, while the sub-frame and hub-carriers are also aluminum. The strut suspension has double ball-joints to improve the geometry, and is arranged to give a little anti-dive effect.

At the rear, the five link system is also aluminum, saving 5.5 lg (2.5 kg) and is designed to reduce dive on braking and squat on acceleration. The brakes are massive for such a small car ? 14.2 in (360 mm) diameter discs at the front, and 13.75 in (350 mm) diameter at the rear. Both are cross-drilled, but somewhat surprisingly, the calipers are the swinging single piston type.

The forged 18 inch wheels ? 19 inch as an option ? carry 245/40ZR front and 265/40ZR rear tires. Plenty of rubber in contact with the road.

Of course, there is plenty of electronics to help you on your way including ABS, traction control, stability control and there is also the option of electronically controlled dampers with three settings ? there are also three settings for the engine control unit as well, to adjust the way the power is delivered according to the way you want to drive.

Inside, there is a the usual simple but efficient office for the driver, with a pair of black instruments with white numerals and red needles. The console is new, and there are the usual options including navigation, but also a wide range of trim materials.

Supercar performance from an 'ordinary' coupe

Clearly, the BMW M3 gives you supercar performance in a practical but good-looking coupe with four seats. Because it is based on the under body of the 3 Series it is quite heavy with a curb weight of 3,480 lb (1,580 kg), but then so are all cars produced by the big manufacturers these days.

Unlike many supercars, the BMW M3 is designed to be used every day, but has still been developed on some of the most difficult roads in Europe, including the Nordschleife of Nurburgring, so we can be pretty certain that the M3 will handle as well as this stunning engine will accelerate it, rasping its way to the red line of 8,400 rpm whenever you want it too.