BMW 645Ci
Test Drive

BMW 645Ci

Let's start with something other than the start of the transmission. This is one of the two most worthy elements of the six that make the Bavarian product fantastic.

The power and torque plant, built into the bow, is distinguished by a number of technical solutions that put it directly at the forefront of modern design among gasoline engines. I won't go into the technical details as they are listed and briefly described in the tech corner. Therefore, at this stage, I will focus on the sensations that built-in technology and knowledge evoke in the driver.

The bare numbers 8, 4, 4, 245, 333 and 450 are more than eloquent evidence of how this machine makes the observer feel. The first number describes the number of cylinders between which the engine displacement is divided, which is written under the second number. The third number describes the rated power in kilowatts, the fourth is the same figure, except that the unit is horsepower, and the fifth number describes the maximum torque.

If I translate these figures into measurable facts, then the data on acceleration from 0 to 100 kilometers per hour in a short 6 seconds (the plant promises even less than 2 seconds) and a maximum speed of 5 kilometers per hour are very indicative. The number and good suitability of the stable under the front cover is also evidenced by the fact that the acceleration even at maximum speed is still so great that passengers feel the "deceleration" with which the electronics stop the acceleration of the "six" at a speed of 8 km / h.

I would venture to argue that the speedometer needle in 645Ci is likely to stop well above 260 km / h. That is, if this unnecessary speed limit were not spelled out in the electronics. The engine convinces across the entire rev range with its powerful flexibility that even modern turbo diesel engines would not be ashamed of.

Considering that flexibility is available over a wide range from 700-minute mainshaft idle to 6500 rpm, any even more powerful turbodiesel that kicks most effectively only in a narrow range of the engine is extinguished. speeds from about 1500 (this figure is very optimistic for many diesel engines) to a maximum of 4000 main shaft revolutions per minute.

When you open the front cover and look around the engine, you find that there is at least one more space in the nose between the engine and the radiators for the V-cylinders, or in other words, there is enough room for the (even more powerful) V-XNUMX.

Of course, the Bavarians did not and will not leave this space unused as they have already developed a larger and more powerful engine that they will (or have already installed) in the M6 ​​model. How fast the latter will be, I prefer not to think about, because all racing wishes are more than perfectly fulfilled by the 4Ci's 4-liter engine.

The engine in the test car was mated to an excellent six-speed automatic transmission that shifts smoothly and quickly enough as is usually the case with Beemvee automatic transmissions. And if I forgive the gearbox 95 percent of the time, or even welcome the fact that even in manual mode it shifts up when the engine reaches the red field, then that behavior is discouraged during a racing adrenaline rush during corners.

It may then happen that during acceleration, the transmission shifts to a higher gear just before entering a corner, even if the driver has already released the accelerator pedal. To convince the transmission to downshift again, the vehicle speed needs to be reduced slightly. This usually happens right in the middle of a corner, which is not conducive to driving stability, as (but not necessarily) such shocks in the drivetrain can be harsh and unbalance the vehicle.

Thus, cornering is better suited to a standard manual transmission, while in all other driving conditions the automatic transmission will match the Goethe range perfectly.

Who would have thought, a 4-liter V-4 can be quite economical too. The idea of ​​walking less than ten hundred kilometers is utopian, but a good eleven liters per XNUMX kilometers using the right foot is not out of reach.

Of course, the consumption with a heavy leg is quickly approaching twenty, but on average it rather hovers around 14 liters per 5 kilometers. However, the fuel tank is incomprehensibly small, the volume of which is seventy liters, and the average estimated fuel consumption forces the driver to visit the gas station at least every 100 kilometers, or even earlier.

At the beginning, I wrote that the transmission is just one of the two supposedly most important elements of the new Bavarian coupe, which justify the fantastic nature of the whole package. The second can only be the chassis together with the helmsman. That the people of Munich rightly collect praise from all over the world in this area is once again confirmed by the new six.

Their progress is confirmed by the ideas of Dynamic Drive and Active Steering. The first takes care of the lowest possible body lean in corners, while the second takes care of adjusting the steering gear for each individual turn (a more detailed explanation of both is given in the technical corner).

The suspension is mostly tuned for sporty stiffness, but as a result, the car does not cause discomfort under any circumstances. Driving on intercity roads will be awkward on short and sharp bumps, but on the other hand, accumulating kilometers on highways, due in part to higher travel speeds, will be comfortable enough to reach your destination hundreds of kilometers away.

The car also shows two faces even when cornering. Here, the different qualities of the base from the Six bring to mind different characters. In general, the coupé behaves like a front-wheel drive car, as it squeezes into the front end when cornering (understeer). And if you think you will make him overdo it by adding gas, think again.

Then the outer wheel "sticks" very well to the ground, as a result of which (when the DSC stabilization system is turned off) the inner wheel turns into an empty space, rather than sliding all over the rear. A conventional mechanical differential lock will come in very handy here, but for the past few years it has only been reserved for the sportier M models.

That's why you don't miss out on the differential lock on slippery surfaces. There the six, with the help of large cavalry, very quickly becomes a thoroughbred rear-wheel drive. ... BMW. On smooth pavement, the two rear wheels slide together much faster, so oversteer shouldn't be a major issue.

However, in order to reduce unpleasant moments (for less experienced drivers), the active steering system guarantees. At lower speeds, it has a more direct transmission in the steering system, which means less steering wheel turns while taming the rear as is customary.

Another advantage of Active Steering is that it can subtract or add the steering angle of the front wheels in oversteer or understeer conditions, which stabilizes the vehicle even faster (even when DSC is off). This automatic heading correction is a pleasure for experienced drivers, but they will take it into account and cause the car to slide even more on the sides, which should be enough for first-class driving pleasure.

However, activity has a weak spot in the steering mechanism. Compared to the regular Beemvee steering wheel, it loses some "cleanliness" in feedback, but with the runs you get used to it and appreciate its immediacy more and more.

So the car looks more than convincing on the road, but what about the interior? The 645Ci wants it to be usable for four passengers, but only partially succeeds. This was also confirmed by people in Bemwege, who gave him an eloquent rating of 2 + 2. The problem mainly lies in the space in the rear seats, where the conventionally acceptable space is only enough for people with a height of up to 1 meter.

A prerequisite is also the position of the front seats, which must not be pushed too far back. Regardless of the size, getting a different type of seat would be a gymnastic feat for everyone. The front seats slide forward, but the aisle between the seat and the doorway isn't too big. Front passengers will also experience the character of a Six coupé, as the already low roof is further reduced by an optional glass roof window.

The fact that the 645Ci Coupe does not greatly increase the usability in the cabin is also evidenced by the rare storage space, which is also very small. However, not a coupe at all, the Six cuts off in the trunk. There, when the rear shelf (read: boot lid) is lifted, a 450-liter hole appears, which is also processed with high-quality velor on all sides.

I hope I have already convinced you that the 645Ci is a truly fantastic car. Of course, like any other car, it also has its drawbacks, but the fact is that the inconveniences (rigid chassis, little space in the cabin) are mainly related to the design of the coupe car.

And since the "Six" is mostly not intended for a budding father or mother who would like to take a large family with them on a Sunday trip to the mountains, the aforementioned disadvantages also lose their relevance.

After all, the target group should be wealthy entrepreneurs and successful gentlemen in middle age (40 to 55 years old) who can afford such an expensive car and then enjoy fantastic driving on winding side roads, for example, from Maribor to Portorož. where, at the finish line of the main embankment of Portorož, they find themselves the envious gaze of passers-by.

I tell you - BMW 645Ci: boy, boy, fantastic!

Tech corner

Dynamic drive

The task of the Dynamic Drive system is to reduce the lateral tilt of the body when cornering. The front and rear anti-roll bars are “cut”, and a special hydraulic element is installed between their halves, which overloads the stabilizer in a bend and thereby limits the transverse inclination of the car.

Active steering

As with Dynamic Drive, the steering column has been cut, except that a planetary gearbox was installed between the two strut parts, with which the electric motor can increase or decrease the rotation of the wheels in a corner. That being said, BMW has provided the driver with countless steering wheels for countless turns. The entire system is securely anchored by a self-locking sprocket which, in the event of a system failure, ensures that the driver is not left without the steering system.

Lightweight construction

As with the 5 Series sedan, the six axles and the front of the vehicle (up to the front bulkhead) are made of lightweight aluminum. Both the door and the hood are also made of aluminum. Instead of aluminum, thermoplastic was used for the front fenders. The back cover is also made of plastic; In fact, it is a type of composite fiberglass that the Bavarians call SMC (Sheet Molding Compound) for short.

engine

The eight-cylinder 645Ci engine in the nose is the pinnacle of automotive engineering. The Valvetronic system replaces the throttle valve and, by continuously adjusting the movement of the intake valves, reduces intake system losses and saves the engine.

The dual Vanos system continuously adjusts the opening angles of the intake and exhaust valves. As with the Twin Vanos, the infinitely variable suction port length provides the best power and torque curve.

Peter Humar

Photo by Sasha Kapetanovich.

Second opinion

Matevž Koroshec

Gossip about what he has and what he can do is complete nonsense. "Six", if we talk about the coupe of this class, is close to perfection. What's not perfect? For example, the presence of the sound of the engine in the cabin. That such a superbly tuned eight-cylinder orchestra advertises itself somewhere in the back of the cabin and gets lost in the atmosphere is simply unjustified.

Vinko Kernc

I'm sure: somewhere in Munich, there, in the "four cylinders", sits a man who has an interesting idea of ​​what a car should be. Very similar to mine. Therefore: yes, I will. For one year until toll and insurance are paid.

Dusan Lukic

The first (and only complaint) is that the ceiling is too low, and when the car drives up the hill at 200 kilometers per hour, you can get a headache. Active steering wheel? Great, it's only when you start to turn on a narrow road that you need a lot of practice to feel it. And when you have to sweep your butt, it’s hard to gauge how much you need to turn the steering wheel to keep things under control. The rest of the car, on a scale of 1 to 5, deserves a clean ten!

BMW 645Ci

Basic data

Sales: Auto Active Ltd.
Base model price: 86.763,48 €
Test model cost: 110.478,22 €
Power:245kW (333


KM)
Acceleration (0-100 km / h): 5,8 with
Maximum speed: 250 km / h
Mixed flow ECE: 10.9l / 100km
Guarantee: General warranty 2 years without mileage limitation, 6 years warranty on rust

Cost (up to 100.000 km or five years)

Regular services, works, materials: 312,97 €
Fuel: 11.653,73 €
Tires (1) 8.178,18 €
Loss of value (within 5 years): (4 years) € 74.695,38
Compulsory insurance: 3.879,15 €
CASCO INSURANCE (+ B, K), AO, AO +12.987,82


(
Calculate the cost of auto insurance
Buy up € 113.392,57 1,13 (km cost: XNUMX


€)

Technical information

engine: 8-Cylinder - 4-Stroke - V-90° - Gasoline - Longitudinally Front Mounted - Bore & Stroke 92,0×82,7mm - Displacement 4398cc - Compression Ratio 3:10,0 - Maximum Power 1kW ( 245 hp) at 333 rpm - average piston speed at maximum power 6100 m / s - specific power 16,8 kW / l (55,7 hp / l) - maximum torque 75,8 Nm at 450 rpm - 3600 × 2 camshafts in the head (chain) - 2 × Vanos - 2 valves per cylinder - multi-point injection - Valvetronic.
Energy transfer: the engine drives the rear wheels - automatic transmission 6-speed - gear ratio I. 4,170 2,340; II. 1,520 hours; III. 1,140 hours; IV. 0,870 hours; V. 0,690; VI. 3,400; reverse 3,460 - differential 8 - front wheels 18J × 9; rear 18J × 245 - front tires 45/18 R 275W; rear 40/18 R 2,04 W, rolling distance 1000 m - speed in VI. gears at 51,3 rpm XNUMX km / h.
Capacity: top speed 250 km / h - acceleration 0-100 km / h 5,8 s - fuel consumption (ECE) 16,1 / 8,0 / 10,9 l / 100 km
Transportation and suspension: coupe - 2 doors, 4 seats - self-supporting body - front individual suspensions, leaf springs, cross rails, inclined rails, stabilizer (Dynamic Drive) - rear individual suspensions, spring legs, triangular cross rails from below, two cross beams from above, stabilizer Drive) - front disc brakes (forced cooling), rear disc brakes (forced cooling), rear mechanical brake on the rear wheels (lever between seats) - rack and pinion steering wheel (Active Steering), power steering, 1,7-3,5 .XNUMX turns between extremes.
Mass: empty vehicle 1695 kg - permissible gross weight 2065 kg - no trailer towing - no roof loading.
External dimensions: vehicle width 1855 mm - front track 1558 mm - rear track 1592 mm - ground clearance 11,4 m.
Inner dimensions: front width 1530 mm, rear 1350 mm - front seat length 450-500 mm, rear seat 430 mm - handlebar diameter 380 mm - fuel tank 70 l.
Box: Trunk volume measured with AM standard set of 5 Samsonite suitcases (total volume 278,5L):


1 × backpack (20 l); 1 × aviation suitcase (36 l); 1 × suitcase (68,5 l); 1 × suitcase (85,5 l)

Our measurements

T = 14 ° C / p = 1030 mbar / rel. vl. = 45% / Resin: Bridgestone Potenza RE 050A
Acceleration 0-100km:6,2s
402m from the city: 14,4 years (


162 km / h)
1000m from the city: 25,7 years (


211 km / h)
Maximum speed: 250km / h


(See in VI.)
Minimum consumption: 11,4l / 100km
Maximum consumption: 19,8l / 100km
test consumption: 14,5 l / 100km
Braking distance at 130 km / h: 61,7m
Braking distance at 100 km / h: 36,2m
AM table: 39m
Noise at 50 km / h in 3rd gear64dB
Noise at 50 km / h in 4rd gear63dB
Noise at 50 km / h in 5rd gear63dB
Noise at 50 km / h in 6rd gear63dB
Noise at 90 km / h in 3rd gear62dB
Noise at 90 km / h in 4rd gear61dB
Noise at 90 km / h in 5rd gear60dB
Noise at 90 km / h in 6rd gear59dB
Noise at 130 km / h in 3rd gear66dB
Noise at 130 km / h in 4rd gear64dB
Noise at 130 km / h in 5rd gear64dB
Noise at 130 km / h in 6rd gear64dB
Test errors: unmistakable

Overall rating (368/420)

  • The end result is not surprising. An excellent mark of five eloquent testimonials to the excellence of a sports and touring coupé. Driving pleasure is guaranteed in all conditions. Or, to put it in "one" word; boy, boy ... fantastic!

  • Exterior (14/15)

    The photos are unconvincing, but in fact the car is beautiful. The workmanship is partially degraded only by the slightly tighter closing of the door.

  • Interior (122/140)

    He looks like a coupe, useless and noble like a Bimvi. The trunk is surprisingly spacious. Ergonomics are also excellent thanks to the improved iDrive.

  • Engine, transmission (40


    / 40)

    All the points obtained are eloquent testimony to the excellent chosen combination of an excellent engine and an excellent gearbox.

  • Driving performance (94


    / 95)

    The active steering wheel is to blame for the missed point. It has some of the cleanliness of feedback from a superb regular Beemvee steering wheel. The car is a traveling athlete.

  • Performance (34/35)

    We only accuse him of accelerating four tenths faster than the plant promises. We also ask ourselves: why exactly M6?

  • Security (20/45)

    The brakes are great, the safety equipment is perfect. It's only a matter of poor rear visibility, but frustration is offset by the built-in parking aid.

  • Economy

    The base 645Ci is already expensive, but it can be more expensive. Fuel consumption is acceptable and the projected drop in cost is large. For this money, there should be more guarantees.

We praise and reproach

driving pleasure

engine

Transmission

chassis

position and appeal

Dynamic drive

Active steering

trunk size (coupe)

engine sound

ergonomics (iDrive)

uncomfortable chassis on a bad road

internal (not) capacity

small fuel tank

PDC warning too loud

price

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