Quad pipes identify the M5 from the rear.

But before we get to the car's hardware, let's walk around it. Whether you're a 5 Series traditionalist bemoaning the Post- Bangle Decline or one of the forwardleaning Moderns relieved to see BMW at the cutting edge in style as well as technology ----editor Carlson happily counts himself in this group, which he refers to as the Dark Side----some elements of the M5 design are beautiful by definition, as Form Follows Function: That which works is always beautiful.

The Kabuki face of the 5 Series receives a significant make-over in the M5. The fiveliter V10 engine needs twice the cooling air required by the 545i's 4.4-liter V8----and besides, M products are expected to look aggressive and challenging. The small spoilers appended to the left and right reduce lift and increase high-speed stability. The rear end also receives a purposeful make-over, and features the traditional four M exhaust pipes; even if you delete the M5 badge on the trunk, these pipes are the giveaway. The handsome 19" wheels (8.5" front, 9.5" rear) are cast aluminum and support specially-designed tires of 255/40 ZR19 and 285/35 ZR19 dimensions; these run-flat tires were developed by Continental specifically for the M5, as the exacting and precise transfer of g-forces in wet and dry conditions was a priority.

The M5 has presence, especially in the very lovely Silverstone II color (silver metallic with a touch of blue) of the cover car. The other exclusive M5 colors are Sepang Bronze----which members saw unveiled at Oktoberfest and on last month's Roundel cover----and Interlagos Blue. You may also order your M5 in Alpine White, Black Sapphire, or silver-gray metallic. Personally, I still can't come to terms with the rather tall side view and small greenhouse and rucksack trunk. But overall, the made-over car looks very handsome and muscular----essential aspects of a car that will cost over 86,000 euros on the Continent (including 16% VAT).

THE V10 ENGINE

M engineers are justifiably proud of the M5's five-liter 90-degree V10 engine and its sophisticated electronic controls. All those euros poured into Formula 1 need to show up somewhere in the BMW model palette; F1 technology made possible the compact high-speed stress-tested electronics that are an in-house development. The BMWWilliams F1 engine was its inspiration. The M motor, though, lasts longer than a weekend, and does not require an entourage of mechanics, engineers, and laptops to keep it running. The M5 V10 has a 25% performance increase over the E39 M5's V8---- but gains no weight in the process.

The maximum output of 507 horsepower (DIN) is reached at 7,750 rpm, and the engine redlines at 8,250. At 8,000 rpm, by the way, those ten pistons cover a distance of approximately twenty meters per second, compared to 25 m/sec at 18,000 rpm for the F1 motor. Maximum torque is 520 Nm (383 footpounds) at 6,100 rpm. This is not a peaky engine, since 80% of the torque is available by 3,500 rpm; flexible is the word.

The hypereutectic aluminum-silicon alloy low-pressure gravity-diecast block---- say that quickly three times in succession! ----is cast in Landshut, the birthplace of the current F1 motor. An aluminum bedplate, with integral cast-iron inserts, insures high-precision alignment of the forged hightensile- steel six-bearing crankshaft; with a cylinder spacing of only 98 mm (92 mm bore, 75.2 mm stroke) the crankshaft can be kept very short for maximum torsional stiffness. High-temperature-resistant ironcoated aluminum pistons----weighing just 481.7 grams, including pins and rings---- provide 12:1 compression. The trapeze-top connecting rods are fracture-split at the big ends ("cracking" con rods instead of cutting and machining them makes for a stronger connection). Low weight and weight matching of reciprocating components permit the lofty 8,250 rpm limit.

The head is also cast in Landshut, and the moving mass of the valve train has been reduced by 17.5% in comparison to the M5 V8 by such means as hollow camshafts. The two intake valves are 35 mm in diameter, the two exhaust valves 30.5 mm. The delicate valve stem measures a mere five mm, which creates very little resistance for the incoming air charge. Hydraulic valve tappets keep valve clearance in perfect alignment----a unique feature for such a high-revving motor----and provide a nice reduction in service cost: no valve adjustments every umpteen miles.

BMW's unique bi-Vanos variable camshaft system has been further refined; through a set of sprockets, some Simplex chain, and a twospeed helical gear box, it can adjust the intake cam over 66 degrees and the exhaust cam over 37. Increased performance, no lumpy idle, a flat torque curve, lower consumption and emissions ----it's a win-win-win situation. The extremely high oil pressure required to make the bi-Vanos system work comes from a radial-piston pump that increases engine-oil pressure to 80 bar (1,160 psi).

Considering the g-forces that the M5 is capable of generating, a standard oil sump and pump arrangement would quickly result in a kaput motor due to oil starvation: The car corners at over one g, decelerates at 1.3-plus. The engine actually has four oil pumps; the two which pick up the oil from the outer cylinder heads are electronically controlled, supplying the main pump whenever lateral acceleration exceeds 0.6 g. There are actually two small oil sumps, one with a transfer pump that moves oil into the larger rear sump where the main oil pump is located. This is as close to a dry-sump oil system as you can get.

What is missing from this engineering masterpiece is BMW's brilliant Valvetronic air-flow system. It does not have the capacity of operating at these high rpm, nor can it give the lightning-fast response to throttle input that an M engine requires. Having driven a supercharged 500-plus-hp MTM Audi A8 and a supercharged 500-hp Alpina B7, I can attest that, while their power is more than sufficient, neither matches the throttle response of the M5. Credit goes to ten individual throttle butterflies that are fully controlled by sophisticated electronics; two potentiometers determine accelerator position 200 times per second. The response time from idle to fully open is only 120 microseconds.

Alas, the ten intake trumpets----visible in the photographs from the M engine shop----are hidden under two huge intake plenums. (A few years ago, Herr Prommesberger promised me in an interview to make M engines more dramatic. How about making the trumpets in carbon fiber and installing viewing windows in the plenum? And can we have some excitement on the air-filter housings?)

Another beautiful sculptural component, this one in stainless steel, is mostly hidden from sight. The five-into-one hydro-formed (at hydraulic pressures up to 11,600 psi) 0.8- mm-thick headers are a visual delight. Two small catalytic converters live very close to the headers for quick start-up temperature, and two larger converters are placed downstream to complete the cleaning process. The V10 meets the demanding European EU4 and USA LEV2 standards.

The MS S65 Engine Control Unit----a highly advanced computer derived from, but more complex than, the ECU used in the F1 program----is a BMW in-house development, and consists of more than 1,000 individual components. Three 32-bit processors perform 200,000,000 individual calculations per second; the M3 control unit from four years ago was only oneeighth as fast and had just a tenth of the S65's memory capacity.

Another interesting innovation----"amazing" may be more appropriate than "interesting" ----is the development of the ionic-current technology used to detect engine knock, misfiring, and combustion misses. When a cylinder's fuel charge is ignited, the high temperature and pressure during combustion partially ionize the air/fuel mixture, and the flame front becomes conductive due to the generation of these ions. BMW's ECU measures the degree of ionization----using the spark plug as a sensor to measure the gas flowing between its electrodes! An amplified signal is sent back to the MS S65 computer, which makes immediate individual adjustments to the ignition process for all ten individual cylinders. This allows the 12:1 compression ratio to burn available high-octane gasoline.

SEVEN-SPEED SMG GEARBOX

The five-liter V10 makes 50 horsepower per cylinder and features elegant sculptural exhaust headers and beautiful intake trumpets? which are invisible once installed in the car.

The new Sequential Manual Gearbox (SMG) III transmission matches the refinement of the engine: a seven-speed manual gearbox with Drivelogic functions developed and built by Getrag exclusively for the M5. It is not an adaptation of a regular transmission with SGM add-ons, it is a whole new concept, including the multidisc clutch activated by a hydraulic transmission control system whose actuators and control unit are built into the gearbox housing. As hydraulic fluid (pressurized to 1,300 psi) moves a piston in the clutch master cylinder, sophisticated sensors on both sides of the piston monitor its travel. The computer actually starts pulling one gear out of engagement at the same time it begins to push another one in; this procedure allows the new SMG III to shift 20% faster than its SMG II predecessor. Those who found previous SMG boxes "too slow" should have no worries; shifting speed has been reduced to 65 milliseconds. ("We could cut another twenty," says one transmission engineer, "but it would seriously increase wear on the synchros.") The transmission, designed for a 550-Nm torque limit, can easily handle 8,500 rpm.

The use of seven speeds is not to keep the engine in a narrow torque band, but rather to allow more frequent shifts with less of a jump between gears----to eliminate the jerkiness of a normal off-the-gas, inwith- the-clutch, out-with-the-clutch-andgo- again shifting procedure. Sixth gear is direct at 1:1, and seventh is an overdrive.

To increase the shifting speed, as well as strengthen the gearbox, the gears are mounted on two shafts, with the lowest gears mounted closest to the bearing housings. The gear arrangement is ideal for computerized "overlap" shifting, but it completely eliminates any possibility of using the seven-speed as a "left-leg" manual; the shifting gates in the console would have no logical sequence to follow. BMW, of course, sees the SMG gearbox as a technical advance, and is somewhat perplexed at the American demand for a footoperated clutch. (In conversations with BMW AG product director Dr. Burkhard Göschel, Roundel editor Carlson suggested that perhaps Americans see the SMG as being too much of an automatic transmission. "Maybe," sighed Göschel, "we never should have given them the ?automatic' options.")

The V10's power is transferred through a twin-disc diaphragm clutch.

Indeed, as with previous units, the SMG Drivelogic program gives the driver eleven options, five in Drive and six in Sport Mode; Sport Option One is leisurely and soft, while Option Six is blindingly fast----and noticeable. In Drive mode, the gears are shifted automatically; the higher the program number, the quicker the shift. Adata bus permits the engine management unit to discuss particular programs and actions with the SMG control unit; Drive mode also recognizes excessive torque drag from the rear wheels under slippery conditions and will open the clutch for a split second to prevent wheel lock-up. A hill-detection mode prevents excessive gear hunting and responds to the steepness of the gradient. In both modes a climbing assistant permits starts on hills without rolling backwards. (My 1954 Studebaker Silver Hawk had this, too.)

One point often overlooked by journalists is the reason for all the shifting options. It is not that BMW has tried to tailor shifting options to eleven different sets of driving conditions; rather, since shifting----especially shifting by a BMW M enthusiast----seems to be a personal style, the M5 driver will, through a course of pleasurable experimentation, find the mode that best suits his or her driving style and comfort level, and spend most of their time in that mode.

SUSPENSION AND HANDLING

Whoever expected a technological leap in the suspension department on the level of the V10 engine and seven-speed SMG transmission may be disappointed. True, all this power must be transferred to the Autobahn, but the existing M magic is sufficient to the task; M products are more about feedback and control (no Active Steering), and the basic suspension architecture is very good to begin with. Active road stabilization is also not on the menu; with lower, stiffer springs, anti-roll bars, and elastokinematics, there is no need for it. And its absence results in less weight, fewer complications, and lower costs.

The basic 5 Series suspension architecture has been maintained, but subtly modified to make it worthy of an M logo. As with the standard 5 Series, the double-joint spring/ strut front axle is completely cast in aluminum. A thrust plate unique to the M5 ensures maximum lateral stiffness of the front-axle sub-frame. This plate also features two NACAair ducts that direct cooling air to the transmission without adversely affecting under-body air flow. Separate bearings are used for suspension and shock absorbers. Of course, the springs are stiffer and lower, and the dampers are of the electronic type. They give the driver a choice of comfort, normal or sport----the latter being a race-track program. I have been assured by M engineers that in the comfort setting, the M5 rides even better than the 5 Series sedan it's based on. My time in the M5 was limited, so I can't give a complete picture of the three suspension modes on a variety of surfaces. (I am gladly offering my posterior for extensive, further test sessions!) But, ultimately, who buys an M5 for comfort?

The SMG III gearbox may be controlled from the console or steeringwheel paddles.

The rear axle is also a carry-over, but uses reinforcement at various supports, links, and joints to better handle the higher stress levels. Special elastokinematics, connectors, and bushings replace the softer stock items, resulting in greater precision---- and, of course, a greater affinity between posterior and road surface.

M engineers like to talk about a total suspension package, from the tires to the padding in the seats. Tires are indeed an important part of that package; run-flat tires, due to much stiffer sidewalls, transfer more ride harshness, which necessitates retuning the whole suspension. The mostly excellent road surfaces in Bavaria will rarely bring out the worst in this type of tire construction. (My experience with 19" run-flat tires in the U.S., in a 645Ci with sport suspension, was not encouraging. I found the ride rough----and unacceptable in this class.)

But the run-flats have major advantages. No spare means a weight saving of twenty kilograms and more trunk space. In addition, catastrophic blow-outs are pretty much eliminated----an appreciated safety bonus, with this performance potential. The Tire Defect Indicator (TDI) will warn the driver of lost air pressure, and the secondgeneration M Mobility System (MMS) will seal holes up to six mm. (Just make sure the gunk inside the tire gets removed after proper repair.) Considering the loads the M5 is capable of generating, a new tire is probably a better choice.

GET IN. SIT DOWN. HANG ON.

Time to get in the car: Opening the doors with sweaty palms and elevated heart rate, I ease myself into the sumptuous Merino leather M multi-function seat (optional). I realize instantly that to get the ultimate "feel" of the car and this buttery leather, I should be dressed only in driving gloves and shoes, and perhaps a modesty apron: total sensual immersion for maximum feedback.

The interior is available with a full leather treatment that includes the instrument panel and an Alcantara Anthracite roof lining. This makes for an especially richlooking (and costly) M5. The chrome rings around black-faced instruments have the traditional M red pointers and require frequent monitoring to keep your license intact. Even better is the optional head-up display that highlights the dynamic engine speed range, and via shift-light function, signals optimum shift points----mega-cool.

Starting is still conventional, but nothing else is. The sound of the V10 as it approaches its 8,250 rpm redline gave me goose bumps and made my hair stand up; it is an almost erotic experience. This is one of the best mechanical sounds in the automotive universe. May I suggest to M to produce a CD sound track of Hans Stuck doing the Nürburgring? This will be an eight-minute piece----short by symphony standards, but amazing for a four-door sedan orchestra with a four-golf-bag-capacity trunk. Ladies and gentlemen, one could rent out expensive rides in an M5 just for the auditory/mechanical stimulation.

Small airfoil elements increase stability at high speeds.

As each symphonic gear reaches its crescendo, shifts may be executed via the anatomically-correct shift knob in the center console or with the plus paddle on the right and the minus paddle on the left of the steering wheel. Due to my limited time window, further shortened by frantic picture- taking, I was unable to sample all the shift-program options. I did not try the automatic program D----neither would you----and left it mostly in sport mode four, which means pretty fast and noticeable shifts. I have long been a proponent of SMG----in manual mode only----and even asked for more gears in its first and second generations, just to hear the perfectly-blipped down-shifts. Thanks, M, for giving us seven (should we expect eight in the new M3 V8?).

Of course, SMG III also has launch control. The driver disengages DSC, selects S6, pushes the gear selector forward, and fully depresses the accelerator pedal; the engine revs to optimum take-off rpm, the driver releases the gear selector, and all hell breaks loose as Drivelogic shifts through all seven gears. As the brochure says, "frequent use leads to premature component wear." Having experienced this violent action in various M3 products, could not bring myself to subject this fine machine to similar treatment.

BMW's traction-control wizardry has also been retained in the M5, but the M3 CSL's M dynamic mode was carried over in modified form to the M5. Press the button on the steering wheel, and the DSC intervention logic will act much later. Please, save experiments with this program for tracks with lots of run-off room; electronics can be helpful, but they cannot negate Newton's laws. For the truly talented----the likes of Hans, Boris, and Bill----the whole electronic safety net can be switched off. Try this on the salt flats of Utah, starting out with the P400 power mode button: This reduces the V10's horsepower by 100 via less-aggressive engine mapping. In other computerassisted areas, a multiple-disc clutch in the differential is capable of directing 100% of the power to one wheel if excessive loss of traction is detected in the other. In combination with DSC, it should make for surefooted winter car, if equipped with the appropriate tires on all four corners.

After extensive time with Active Steering in the 5 and 6 Series, I can fully understand the M engineers' decision to leave it out of the M5. Active Steering is great for those challenged by parking lots, and it does make 180-degree switchbacks a blast. But its nonlinear response to various types of corners and lack of road feel made M stay with a Servotronic system. This controls steering assistance in relation to road/engine speed in the M5. It offers a sport program that is more direct and responsive for maximum feedback, or one can go to the comfort setting.

Once you have overdosed on the sound and scared the neighbors, better check the numbers: 100 kph (62 mph) arrives in less than five seconds, and 200 kph (124 mph) takes only fifteen! (Traditionalists may remember the impressive acceleration of the first M5: 0 to 100 kph in 6.1 seconds, 0 to 200 in 26.) The thrust is simply unrelenting, and finding the right gear never a problem. The capabilities of the M5 are so advanced that a driving course is a wise investment, and it is prudent to match your abilities to the car's. On public roads this machine can handle anything with ease and utter confidence ----and I do mean anything: Though top speed is electronically limited to 250 kph----155 miles an hour----an ungoverned M5 would easily exceed 300 kph (more precisely, 330 kmh/205 mph). Compare this with the E28 M5's top speed of 251 kph.

The front of the M5 has been designed to double the cooling-air intake.

Coming down from those speeds is accomplished with drilled, ventilated compound brakes running 374 x 36-mm front and 370 x 24-mm rear rotors, clamped by twin-piston aluminum sliding calipers (similar to what is used in the heavier 7 Series). During development, four- and six-piston calipers (like Brembo's) were tried , but the in-house brakes proved to be more capable and cost effective, and much quieter----in all, a more user-friendly arrangement. These brakes put deceleration into sports-car territory: 100 kph to 0 in 36 meters, and 200 kph in less than 140 meters.

Compared to the "Ur" M5 from the mid- '80s, the new one is definitely bigger and heavier----a problem that seems to affect the population in general, the income bracket destined for M5-hood no exception. If you drove all M5 models back-to-back you would realize how involving the first one already was. But the latest one is much faster, more agile, and safer. We want comfort and gadgets, and that equals weight.

Speaking of gadgets, how do you keep the driver and passenger planted in their seats under vigorous driving conditions? Answer (to a question that occurred only to M): Order up the optional M multifunction seat with active backrest width adjustment. A button on the lower dash lets you select Comfort, Normal, or Sport (or use the M drive program on the steering wheel). Depending on lateral acceleration and steering- wheel angle, a cushion will magically appear and disappear under your armpits to keep you properly positioned. Try this on a windy road and you will get a full latissimus dorsi muscle massage. What's missing is a "grip hold" button for the ticklish.

The heart of the matter: The V10's central processor contains over 1,000 components? and ten times the memory of the M3 ECU.

THE SUM OFALL FIVES

This new M5 is a masterpiece. It is designed for the knowledgeable and competent enthusiast, demanding involvement and rewarding expertise. This sportive sedan has ample room for four and carries you in style, via whatever path you choose, to the Nordschleife. My short experience in the M5 equals a delectable appetizer; I can't wait to sit down for the full seven-course meal!

On a personal note: I happen to be the first journalist worldwide to drive the new M5. The story of the official M5 model launch will run next month in Roundel---- but I am pleased to prevent a brief preview. I thank everyone involved for making this----my 100th Roundel cover----a very special experience.