BMW CS Series
Reviewed by Unique Cars and Parts
Our Rating: 3
The Best of BMW Classics
The CS coupes are among the best of all BMW
classics. Ignoring the under-powered 2000CS of the early days, other CS coupes had the best six-cylinder engines in the world - powerful, smooth and refined. All CS coupes offered the remarkable build quality and driver comforts, plus exceptional handling
for a 4-passenger car. Among them, the 3.0CS series was the most popular, no doubt due to the brilliant engine.
While the 180 hp 3.0CS and 200 hp fuel-injected 3.0CSi were already attractive, BMW
engineers went on to produce an even more desirable variation - BMW 3.0CSL ( "L" stands for "Light" ). This car adopted some aluminium body panels to reduce weight, plus many exaggerative aerodynamic
kits including the huge rear wing which gave it the nickname "Batmobile". It was designed by Giugiaro (3.0CSL only, not the whole CS series), that was probably his most aggressive design.
Like the BMW 2002 turbo
, the BMW 3.0CSL was aimed at motor racing, although the racing version was actually powered by a 3.5-litre 24-valve straight six which eventually adopted by the M1 mid-engined supercar. Early road version 3.0CSL's used the same engine as 3.0CSi, then revised a little bit to 3003cc., and at last enlarged to 3153cc with 206 hp.
Tracing the Lineage
As a series the big BMW CS went all the way back to 1966
when it was first introduced as the 4-cylinder 2000CS
. Its unusual body shape, with vast glass areas, low beltline and boxy-but-rounded lines, was impressive then but it had an awkward-looking front end and its 2-litre engine
just didn't give it the performance it deserved. Then in 1969
came the new 6-cylinder engine and the big sedans BMW designed to compete head-on with Mercedes
Rather half-heartedly, it seemed, the individualistic little Bavarian carmaker also showed a face-lifted coupe using the same CS body from the windshield back but with an altogether more harmonious front end just long enough to accommodate the 6-cylinder engine. Half-heartedly, we say, because the new coupe retained the old 4-cylinder's drum rear brakes
and narrow rear track. It was as if BMW
had said. "Okay, we have these CS bodies from Karmann, we have to do something with them."
The Definition of a Grand Tourer
Despite the composite nature of the car, however, it worked. The brakes
weren't as good as those of the cheaper 2500 and 2800 sedans and the narrow rear track gave the car a strange crab-tracked look from the rear. But the CS Series looked good, performed like an athlete with the brilliant BMW six, produced some of the most delicious mechanical noises known to man, and had interior and boot accommodation that could be used to define the term Grand Touring.
Never intended to be a volume seller anyway, the model apparently fulfilled or exceeded BMW's market expectations for it, and when the 6-cylinder engine got its first displacement increase the coupe became the 3.0CS and got proper disc brakes
for the rear - actually ventilated discs all around, whereas the 2800CS only had solid discs at the front. Strangely, the narrow track was left narrow and the car still looked as if it were crab-tracked, at least with the too-small tyres
fitted to export cars. Strangely, it was only in Europe that the CS came with fat 195/70-14 V-rated tyres, and on the lightweight 3.0CSL
version these are fitted to 7-inch rims instead of the standard 6-inchers, so it may have been necessary to leave the track narrow to accommodate the extra width.
A Near Perfect Design
had a 200-bhp fuel-injected engine, and there was an intermediate 3.0CSi with the injected engine but normal luxury fittings. In the USA only the basic model, with its carburetted engine detuned for emission control, was available. But no matter which version it was, the CS looked right - crisp, aggressive and functional without straining to be swoopy. It was obviously not as overt as the De Tomaso Pantera
was, for instance, but it still looked the goods, and was enough to pull a small crowd when parked - even to this day. It looked far better with the wider tyres
. Perhaps the only blemish on an otherwise near perfect design were the large side reflectors found on US versions - this being required to meet safety regulations. The amber front one sat just behind the standard side lighting unit and looked awkward.
, to meet yet another U.S. regulation, the bumpers were moved out a bit from the body and the front bumper-guard tips were redesigned. The length increase was minimal (3 in.) and the aesthetic effect negligible. The CS interior looked right too. There was not a trace of ostentation, but everything was there, tastefully and simply done. Leather upholstery was optional at a stiff price but not many CS buyers would have wanted to forego it, so re-upholstering with leather when performing a restoration would be the only way to go. The front seats were superbly designed - fully supporting, generously dimensioned and adjustable through 75 degrees. The rear seats were equally good, although they lacked some of the headroom and more than a little legroom, and had a fold-down center armrest between them. There was tasteful chrome trim on the seat framework and stainless steel finishing off the door jambs - the BMW CS always impressed with its elegant detail work - something you would never get sick of.
Behind the Wheel
Legible instruments, though not enough of them (no BMW
production model to 1975
had an ammeter or oil-pressure gauge
), were set into a pod and all controls were within easy reach of a fully belted driver. To the right of the pod was a strikingly simple arrangement: a shelf with a padded edge and small wood dividers every few inches to keep things from rolling about, all faced by handsome wood veneer. The wood was picked up again in the door and side panels. There were two drop-down bins, one large and one small, plus snap-flush map pockets in each door. Compared to other cars from this era, we are struggling to find a more luxurious, more comfortable or better-looking passenger compartment - it was that good.
wheel was large - too large for our tastes - but at least it was leather-covered, with a padded rim for good grip. On the steering
column are two control stalks, the left one for high beam and headlight flasher, the right one for indicators, windshield wipers and washers. Having the indicators on the right stalk was great for those exported to right-hand-drive markets who were accustomed to this layout - but unfortunately during the CS's time BMW switched to the standard left-hand-drive stalk configuration, moving them to the left. Electric front windows were optional, although strangely the rear ones were standard - but in both cases the lift speed was very slow in action. They also didn't lower the windows entirely into the body sides, a consequence of the tall windows but seemingly a detail that could have been worked out better. Vision out of the CS was superb - probably the best in any closed car being built in the early 1970s.
On the Road
Driven moderately, the 3.0CS was smooth and very quiet. At cruising speeds the sounds of the muffled, smooth engine and humming XAS tyres blended together in an almost musical way; wind and road noise were low although you were conscious of a concentration of what wind noise there was around the windshield. The big BMW engine was without a doubt the most sophisticated inline six in the world and its note was very much a part of the car's character. To meet ever more restrictive pollution requirements the BMW engineers employed an exhaust-gas recirculation system plus a retarded spark at low engine speeds, and this rendered what was once a beautifully responsive engine
to a somewhat reluctant one around-town. But, when driven hard, it freed up and went almost as well as ever. As an example, road tests of a 1973 3.0CS with an identical test weight to that of a 1971 2.8-litre CS had the acceleration times posted as being almost identical.
One area where the 3.0CS was better than the previous 2.8CS was in its gearbox. The one used with the 2.8 engines was delightful in everyday use. light and precise; but the synchromesh
wasn't always up to fast shifts. It had been redesigned for the 3-litre, and though its action was stiffer it remained pleasant to use and the synchros
couldn't be beaten. A perennial problem remained, in that the clutch made a peculiar noise as it was engaged or disengaged, and it also had a tendency to "chatter" on uphill starts. A 3-speed automatic transmission
was available on the 6-cylinder BMWs; it also had been completely changed and was, by 1971, a satisfactory unit. But the manual gearbox was so good that most drivers, we're sure, preferred it.
A true GT combines maximum performance with maximum comfort. The CS's ride was soft; good handling wasn't achieved here by stiff springs
and super-hard tyres
but rather by all-around independent suspension
, anti-roll bars, radial tyres
and plenty of suspension
travel. The ride wasn't faultless; it shared the BMW family trait of an undue amount of front-rear pitch on gentle undulations - due, we think, to overly soft rear spring
rates. Otherwise, though, it was satisfactory, and despite its pillar-less construction the body was stiff and rattlefree, holding firm over the worst of roads.
BMW used ZF power steering
on the CS and this was almost as good as Mercedes' legendary power assist. It felt a bit light initially, but continued use of the car revealed that it had true road feel. The steering
ratio was about average, not tremendously quick, but a tight turning circle and well-defined body corners made the CS a particularly maneuverable car in traffic or the parking lot - not to forget the great vision either. The CS's brakes
were greatly improved from the 2800CS's disc-drum combination. They were hammered by many car testers and none could induce fade. They even managed decent stopping distances from freeway speed.