[Only the Mercedes-Benz half of the comparison has been reproduced here]
There are cars which are very hard to judge by normal standards. And chief amongst them are the top of the line luxury models that emanate from the few remaining producers of such vehicles - BMW, Jaguar, Mercedes Benz and the rest.
Of these, the last named appears to enjoy a charisma far beyond its real worth. But clever marketing through engineering excellence, proved by an almost unbeaten race track record in post war years, and by such feats of logistics as winning the Singapore Airlines Rally, have built the charisma even more.
It's a little misleading to say that the charisma of the "Benz" is in excess of its worth, as the car really is still the leader in the class, when you get right down to practical super luxury.
In this edition we have tested BMW's 733i, finding that it comes perilously close to knocking off the three pointed star. Close, but not quite there yet. The BMW has a far more sporty image that continues in a very subdued manner in the brilliant 733i, Its engine in six cylinder guise is better too. But the Mercedes, as personified by this test of the 280SEL, still has the narrowest of leads in our book.
Introduced to the world in 1974, the 280SEL has undergone constant refining, so that the car you can drive today, even with ADR 27a restrictions, is very much an example of the state of the art.
Powered by the Bosch electronic fuel injected M110 twin overhead camshaft six cylinder motor of 2746cc, it could be accused of being slightly underpowered at a weight of 1645kg. But this is hardly born out by its performance, especially in the mid speed ranges.
Perhaps the only thing that might strike a note of alarm in the potential buyer would be a paragraph in the Australian version of the owners' manual that states 150 km/h or speeds in excess of that, should not be maintained over extended periods.
It appears that this is purely a precaution on the part of MB as it has been known for misfiring to occur as a result. This is due to the plugs overheating. However, the suppliers of our test car told us that they have never come across examples of such behaviour, and that cruising speeds well above 150 km/h appear to be quite normal amongst owners without trouble, in this department. Even so it is only fair to say that the BMW 733i manual has no such written restrictions. A spokesman for BMW told us that the only restrictions were the normal legal limits and the red line on the tachometer!
Mercedes' engine has all the right bits to make it a reliable unit under all conditions, including solium filled exhaust valves and the like, while its design has been based on ease of maintenance and repair.
The engine drives through a torque convertor to Mercedes' own four speed automatic gearbox. This has a few features of its own worthy of mention.
It can be push started for instance. And so long as the lever is left in drive, should the engine stop, the power assistance is maintained both in the four wheel disc braking system, and in the recirculating ball variable ratio steering.
Engineering finesse is to be found everywhere, this being more important than cost cutting by the German company.
Sumptuous is the only way to describe the first impressions of the large sedan. It's four inches longer than the SE, that extra length providing huge passenger space in the rear seat for limousine work.
Seated behind the over large MB steering wheel the car feels big, and that's the way it drives when the gear shift is left in "D". It seems to require lots of throttle to get it moving from rest, providing a feel of solidity and trustworthiness, rather than the nervousness of a race horse. But use the shifter through the four speeds and it's a different story, as the performance figures show. To this end, that mid range performances, 60 to 100 km/h in 5.8 seconds, is particularly noteworthy.
The seats seem a little on the hard side for short journeys, but occupy them for a number of hours and they soon show up as being well designed to support the body properly, although lateral support could be improved. Adjustment is limited too, the height and fore/aft movements being all there are, with no adjustable steering column. This means that the driver has to adjust himself instead.
The driver of the Mercedes Benz doesn't have to work too hard at sorting out the control system, unlike the BMW owner. It's all pretty straight forward and logical, from the lights, stalk mounted windshield wiper/washer system, to the heater and air conditioning controls.
Perhaps the "Mexico" AM/FM cum stereo cassette player is a little antiquated in design. It doesn't seem to go with all the other modern instruments and the high gloss wood trim, around the place.
Power windows are standard, these operating at a slow speed in the interests of safety.
Other interior features include a rear screen demister, and the now usual first aid kit nestling in a compartment on the rear window parcel shelf.
Suitable luggage space is available for a full compliment of passengers in the large square shaped boot, while there are nets in the front seat backrests for other odds and ends. Extra stowage space is to be found in the front doors, plus of course, the glove box.
Driving is simplicity itself, plenty of feel coming through the car to indicate what is going on. The steering possesses plenty of feel too, despite power assistance. It's quick and easy for quite spirited driving. On a handling run there was no difficulty to setting the car up for long power slides, changing directions without the tail appearing to get away, despite the long length of the machine. At such times no obvious basic trait could be found in the handling or road holding - it simply did as the driver requested.
Second gear is particularly useful for overtaking, running as it does to a maximum of over 140 km/h. It was simple matter of leaving the foot on the throttle and slipping the lever back to "2". The car would then accelerate very quickly indeed so long as revs were around the 3000 mark.
Now fitted to Mercedes Benz is the "Tempormat", a cruise speed control that is fitted to the steering column a little higher than the right hand control stalk.
This can be used almost like a hand throttle, the driver setting the speed he requires, with a small memory under the engine hood looking after things from then on. The cruise speed can be cancelled either by hand or by touching the foot brake, and the memory will remember the set speed should the driver require it later.
Frankly we're not sure whether such features are good or bad. Certainly they seem to take one more object for concentration away from the driver, although there are those who suggest quite the opposite.
For a car of its size, the 280SEL brakes very well indeed, from 110 km/h to a standstill in only a little over 50 metres. Very hard braking will lock the rear wheels and unless the pedal is lifted, they tend to stay locked but proper attention to avoiding this achieves excellent stopping distances. We did not like the parking brake. This protrudes from the dashboard to the right of the steering column. When engaged, it can be something of an obstacle to getting into the car. It's just one penalty of the change from left to right hand drive.
Although generally quiet at cruising speeds, the engine can get a little noisy and harsh under hard acceleration. At idle it is discernable but not to any disturbing extent. Similarly, wind noise is non existent, careful design of strakes around the windshield and along the tops of the doors diverting air flow away. These features also serve to keep windows dry and free from grime longer too.
As one might expect, ride is excellent no matter what the surface, all impacts being dampened to a faint jolt. Even on quiet rough gravel roads, a high standard of insulation is maintained. The good road manners are still there too, giving the driver the facility to cover quite long journeys in the outback, without tiring.
It was in the late sixties that Mercedes at last did away with their low pivot swing axle rear suspension, substituting a semi trailing arm type of design, which certainly works perfectly in conjunction with the double wishbone front suspension, featuring negative scrub radius steering geometry.
With the introduction of the BMW 733i, it really looks as though the $30,000 to $40,000 price bracket in luxury cars is becoming something of a focal point, especially for these two German makers. Now we hear that BMW is developing a diesel to take on the 300D.
As we said at the start of this test, Mercedes had better watch out as there are others starting to tread on its tail!
© September 1978 Motor Manual, Australia.