An interesting meeting in absentia of two exotic car breeds
We are talking about forces - in one case, expressing acceleration, and in the other - on the table. An interesting correspondence meeting of two exotic car breeds, each in its own way demonstrating the extremism of the six-cylinder philosophy.
The six cylinders in a row quietly balance themselves in such a way that no other engine can match this arrangement due to its sophistication. A similar postulate is valid for any in-line six-cylinder unit. However, these two belong to a special breed - perhaps because they are extreme representatives of their own kind. With its 381 hp and only three liters of the working volume of a self-igniting machine, driving BMW The M550d creates an unprecedented image in the fauna of the automotive world and can even be considered a radical expression of downsizing (we have no idea how the 4-turbo version will work yet). “Maybe,” because BMW has barely given up on eight-cylinder engines in the name of downsizing. The power of the N57S unit, of course, does not mean savings - in one of the latest tests, auto motor und sport M 550d noted an average fuel consumption of 11,2 liters. And this is from a car that weighs "barely" two tons. They may look impressive in comparison to the rest of the automotive world, but they are paltry compared to the 40-ton train that travels on the roads. Volvo FH16. With an average consumption of only 39 liters of diesel fuel per 100 km. What is this comparison? Quite simply - both the M550d and the FH16 take the V-XNUMX philosophy to the extreme, a rare occurrence, but only in a family of heavy tractors - whether on-road or off-road.
40 tons is not a problem for this machine. Even on steep road sections, the FH16 continues to maintain its cruising speed of 85 km / h as long as the curves allow it to move in a similar manner. However, in such cases, the FH16 is rarely used and mostly by companies looking for fast transport on steep roads. The real power of this truck is no more and no less than 750 hp. power and torque 3550 Nm, used as a tug for transporting large and heavy loads such as construction machinery or distillation columns for refineries. In Sweden, where, unlike in Europe, the law allows trains heavier than 40 tonnes to travel, usually around 60 tonnes of cargo, such as logs, are transported. Not that it didn't handle the 60 tonnes in question nearly as easily as the 40s, as colleagues at the auto motor und sport subsidiary lastauto omnibus say for trucks and buses.
Maximum torque at 950 rpm
A car with three BMW turbochargers achieves a maximum torque of 740 Nm at 2000 rpm. The Volvo FH16 D16 engine cannot even dream of such speeds. A 16,1-liter car with a single cylinder volume equal to a 2,5-liter beer bottle with another 168 milliliters of bonus, reaches a maximum torque of 3550 Nm at ... 950 rpm. No, there is no mistake, and in fact there is no other way out with a 144mm piston diameter and 165mm stroke. Just before the BMW engine reaches its maximum torque, the Volvo D16 engine reaches maximum power - in fact, it is available in the 1600 to 1800 rpm range.
The history of the D16 dates back to 1993, and over the 22 years of its existence, its power has grown steadily. The latest version of the D16K now has two cascade turbochargers in the name of achieving the Euro 6 emission standard. Thanks to them and the increased injection pressure in the unit-injector system up to 2400 bar, it manages to deliver the aforementioned torque so early. In the name of better mixing of fuel with air, multiple injections are carried out, and the "exhaust gas" cleaning system, which includes a DPF filter, catalytic converter and SCR unit, has a larger volume than the entire trunk of a BMW.
Thanks to the standard all-wheel drive system of the M550d, there is no problem getting all the power to the road. Even in wet areas, the four-seater is unlikely to spin out of control, and thanks to the M-settings of the xDrive system, some back flirting is allowed. The real possibilities of the car can be seen in a rather vivid expression of the limitless speed of the highway, on which most drivers become extras. It doesn't really matter which of the eight gears of the automatic transmission is engaged - over 2000 rpm when the boost system reaches sufficient pressure (max. 3,0 bar), the monstrous torque hits you with all its might and the M550d starts shifting gears cleanly and with incredible precision.
Engine weighing 1325 kg
Volvo FH47 with 16 hp / l cannot match the dynamic acceleration of BMW with its 127 hp. / l. However, a heavy machine with different options for the number of driving axles creates a feeling of titanic power, especially when loaded. Every fiber in your body feels like the start of a 62 tonne and gear shifting of the new I-Shift DC dual-clutch transmission, by the way, the first of its kind on a highway tractor. For trucks and especially the FH16, the architecture of the automatic and dual-clutch transmission is different and includes a basic three-speed mechanism with a so-called range / split gear group providing 12 gears. They are lined up with great precision and with a short hiss of the pneumatic system. All the mass is pushed forward, making you feel the other component of Newton's equation of force. This is not acceleration, but mass. Steep climbs or huge loads - the Volvo FH16 simply inflates its two turbos, injection, yet unattainable for car engines, starts pouring out a lot of diesel fuel (maximum load consumption is 105 l / 100 km), and giant pistons flex their muscles. take this huge load on your shoulders. They have no rest, because sooner or later, when this whole composition has to be stopped, they will have to help the classic braking system. VEB + (Volvo Engine Break) technology, which uses valve control to use compression and exhaust hours to generate 470 kW of braking torque. If necessary, an additional retarder is added to control the weight in the equation.
Text: engineer Georgy Kolev
BMW N 57S
The BMW charging system is a joint venture between the Bavarian company and the BorgWarner Turbo System and is not called R3S. In practice, this is an upgrade of the R2S turbocharger used by the same company. The difference between the two is that a third, again small, turbocharger is housed in the wastegate connecting the small and large turbochargers. With its help, the system becomes parallel-serial - since the third turbocharger pre-pumps air for the large one. The crankcase is connected by head studs - this architecture greatly increases the strength of the engine structure. The crankshaft and connecting rods are also reinforced to withstand the 535d's increased operating pressure from 185 to 200 bar. The fuel injection pressure has also been increased to 2200 bar and a sophisticated water circulation system cools the compressed air.
The Volvo D16 engine, which also forms the basis of the Penta family of marine products, is available in 550, 650 and 750 hp power levels. The latest K version replaces the VTG variable geometry turbocharger with two cascade turbochargers. This allows the filling pressure to be increased over a wide range of speeds. Increased power of the intermediate cooler and decreased compression ratio. This reduces the temperature of the combustion process and the emissions of nitrogen oxides. Even the Bosch-modified BMW system for the N57S cannot compete with its 2200 bar and Volvo with its 2400 bar. The dry weight of this giant unit is 1325 kg.
TECHNICAL DATA BMW M 550d
4910-seater sedan, length x width x height 1860 x 1454 x 2968 mm, wheelbase 1970 mm, net weight 2475 kg, total permissible weight XNUMX kg
Independent front and rear suspension, MacPherson strut front with double wishbones, rear with transverse and longitudinal struts, coaxial coil springs over telescopic shock absorbers, front and rear stabilizers, internally ventilated disc brakes, front / front 245, rear 50, rear rear 19/275 R 35
Dual gearbox, eight-speed automatic transmission
In-line six-cylinder diesel engine with three turbochargers and intercoolers, displacement 2993 cm³, power 3 kW (280 hp) at 381 rpm, maximum torque 4000 Nm at 740 rpm.
0-100 km / h 4,7 sec
Maximum speed 250 km / h
Average fuel consumption (in AMS test)
diesel 11,2 l / 100 km
VOLVO FH16 SPECIFICATIONS
Volvo Globetrotter XL, all steel cab with steel superstructure, both fully galvanized. Four-element air suspension. The frame with cross and longitudinal members is bolted and riveted. Front and rear stabilizers. In the front there are two-leaf parabolic springs, in the back there are pneumatic springs with four airbags. Electronically controlled disc brakes
4 × 2 or 6 × 4 or 8 × 6, 12-speed dual-clutch transmission or automatic
In-line six-cylinder diesel engine with twin turbochargers and intercooler, unit injector, displacement 16 cc, power 100 kW (3 hp) at 551 rpm, maximum torque 750 Nm at 1800 rpm
Maximum speed 250 km / h
Average fuel consumption (in the Lastauto Omnibus test) 39,0 l
diesel / 100 km