BMW 3.0 CSL

PERFORMANCE AT A PRICE

AT-A-GLANCE: Lightweight coupe with fuel injection based on previous CS model. Fantastic performance for a 3-litre, good stability at speed, but fuel consumption heavy when driven hard. Excellent handling, rather firm ride. Good brakes. Very expensive in this country.

(Autocar, Oktober 4th, 1973. UK.)

West German industry has been booming in recent years and as with most industrial nations it is the car producers who are at the heart of the expansion. One of the firms to make great strides is BMW, a keen and youthful organization manufacturing well-engineered cars with outstanding performance. Riding on the crest of the affluent wave throughout Europe, they have increased output from 161,000 in 1970 to 179,000 last year. To keep alive the performance image and stimulate advanced design among their own engineers, BMW have lately been making a concerted competition effort and a major part of this programme has been based on the 3-litre coupe, the fastest model in their wide production range.

   As originally introduced, the Karmann-built two-door coupe body for the BMW 2000 was a low-volume prestige model, finely executed but in no way sensational. A few examples were converted to right-hand drive in this country. With the launching of the new six-cylinder range in 1968, the coupe was completely re-engineered and given some very effective styling changes to become the 2800 CS. At the Geneva Show in the spring of 1971, engine size went up to 3 litres and ventilated discs were substituted to improve the braking, our full test of this 3.0 CS being published on 15 July 1971 when factory-built right-hand-drive examples became available in the UK. A year later fuel injection was offered with manual transmission only, the carburettor engine remaining as a natural mate for automatic on the 3.0 CSA, which is still available.

   In the autumn of last year, just before the London Motor Show, the factory decided to make a limited number of special lightweight coupes in order to homologate their competition car. This version was fitted with an engine enlarged to just over 3 litres to permit further increases in capacity and still qualify for Group 2 racing, the regulations stipulating that engines can be enlarged only without penalty within their homologated class. When the importers saw this model they ordered a large number, suitably civilized with proper steel bumpers and electric windows. At first it was intended to make this CSL the only manual coupe in the range, but customer reaction to the fancy colour scheme and rather delicate aluminium panels has now put the all-steel regular 3.0 CSi back in the price lists. A brief test of this was published on 8 June last year.

   Mechanically therefore the CSL as imported here is virtually the same as the CSi. Bore size is 0.010in. oversize to push the capacity just over the 3-litre limit and the peak output quoted is still 200 bhp (DIN) at 5,500 rpm. Judging by the performance this is probably a very conservative figure and we suspect the power curve goes on climbing above 5,500 to something like 215 at 6,000 rpm.

   Suspension and gearing are unchanged, except for slightly wider alloy wheels with a rim width of 7in. instead of 6in. This increases the track front and rear by 1in., so chrome wheelarch extensions are added to retain spray protection. To save weight, aluminium is used for the outer skins of the doors, bonnet and boot, and much lighter competition-type front seats are fitted in place of the very heavy normal ones with Reutter reclining backrests.

   Because this is claimed to be a “lightweight” version we were most interested to put the CSL on a weighbridge and find it turned the scales at just 143 lb less than the 3.0 CS we tested in 1971. With its plastic bumpers and without the ballast of electric windows and power steering, the German version of the CSL weighs only 2,600 lb – 400 lb less than the 3.0 CS and almost 260 lb less than the British CSL.

   The effect of even this small 5 per cent saving is noticed on the performance, the CSL proving a few tenths quicker on acceleration from rest all the way through to 1sec at 100 mph and over 3sec at 120 mph. From 0 to 60 mph took only 7.3sec and 0 to 100 mph came up in exactly 20sec.

   For a 3-litre four-seater car, this kind of acceleration is incredibly good, especially when it is matched by remarkable bottom-end flexibility and sweet, smooth repeatability. We were able to pull away from as low as 20 mph in top without harshness and despite a fresh 10-15 mph breeze the BMW repeated its time from rest to 100 mph over and over again within 1 sec spread. In the same direction we were often as close as 0.02 sec on our new digital electronic timer.

   It takes only a glance through the times for acceleration in each gear to spot that the secret of this engine lies in a very wide and flat torque curve, increments in third for example over 20 mph ranges each taking exactly 4.9sec from 30 to 70 mph. The strong bottom-end torque is felt even more on the road, when it hardly seems necessary to change gear at all, the very useful third spanning 10 to 100 mph with punch all the way.

   On top speed we were disappointed to find the CSL could not match the 139 mph we had timed the CSi at in France. On two occasions abroad we did not better than 133 mph, which is 3 mph below the manufacturer’s usually accurate claim. At least one other independent source endorses our figure, however, and since the CSL differs from the CSi only by the addition of a front “bib” spoiler, the explanation could be that this introduces extra drag. It proved very effective at reducing front-end lift, and although we never really had any qualms about stability in the CSi without it, the improvement was most noticeable.

   Rich mixture for cold starting is provided automatically by the Bosch electronic fuel injection, and all the driver need to do is turn the key without touching the accelerator. The engine runs at a fast idle until warmed up, when it settles to about 900 rpm. Full power is available without hesitation right away, but wide throttle openings with a cold engine cause an excessive amount of oil smoke. Even with a warm engine there are traces of blue exhaust smoke on the over-run from high revs, yet the consumption overall was a very reasonable 1,000 miles per pint.

   One of the most impressive things about the engine is its smoothness throughout the range, the sweetness actually improving towards peak revs. When idling there is a slight chatter from the injectors which sound like a faint exhaust leak. When the accelerator is floored the response is immediate and the rev counter needle fairly catapults round the dial towards 6,400 rpm – the pick-up from 3,000 rpm on is so brisk that this is an easy engine to over-rev – which is a comforting safety device. On the test car the rev counter under-read by 300 rpm at the top end, so that the cut-out appeared to come in at just over 6,000. When timing the acceleration from rest we were able to break traction after the clutch was fully home and spin the wheels all the way to 30 mph. Second is good for over 60 mph and third runs out at exactly 100 mph. Although first seems low, the progression of the ratios is, in fact, perfect. Restarting on a 1-in-3 gradient posed no problems and the handbrake held facing either way.

   Synchromesh is powerful enough to allow crash-free snatch changes and in normal use the action of the short stubby lever is light and beautifully precise. There is a smooth wooden knob which fits the hand nicely, but on the test car its varnish was beginning to peel off leaving an uncomfortable sharp edge. The clutch, which has plenty of bite to cope with all that torque, needed a heavy effort and had al long (6in.) travel.

   Fuel consumption, we found, varied considerably with the traffic conditions and the type of driving. On a main road journey in this country without using high speed or the ultimate in acceleration it was possible to record figures better than 20 mpg, yet confined to town with more than a fair share of stop-start traffic there were times we recorded as low as 15 mpg. Our overall consumption worked out at 16.7 mpg with a typical journey figure of around 18 mpg. The tank holds a total of 15,5gal, but the gauge is pessimistic over how much remains towards the end and a bright white warning lamp stays lit when less than 2gal is left.

 

Ride and Handling

   Most cars fitted with 70-series tyres tend to ride more harshly due to the extra sidewall stiffness, and the CSL is no exception in this respect. Insulation from bumps and road noise is very good, but at low speed particularly one feels a little too much of the surface details. Driven over larger bumps the car shows an impressive ability to soak up undulations and the damping mostly makes a good job of preventing pitch and float. With a load in the boot or four passengers there is not enough suspension travel left at the rear and the damping reaches the limit of its capacity.

   Power-assisted steering was fitted to the test car, which adds £179 to the already-high price, but it takes all the work out of town driving and parking and leaves plenty of feel. Probably because of the increased front wheel offset, the effort required is greater than on other BMW models, though kick-back is not noticeably worse. Overall the power steering suits the car very well and is among the best systems we have experienced.

   Set up for a long sweeping bend, the cornering characteristic of the CSL is predominantly one of stable understeer., not excessive, but enough to keep the nose from wandering off the chosen line. Flicked through a tight turn in a low gear, the car will hang its tail out in a most satisfying way like the true thoroughbred it is. In between these two extremes the skilled driver can stimulate a nicely balanced neutral kind of handling. The 25 per cent limited-slip incorporated in the rear axle is not enough to cause any handling problems or excessive tyre wear, but it is sufficient to improve traction significantly on slippery surfaces. In the wet it is naturally much easier to provoke wheel-spin and a certain amount of care is needed when moving off briskly from rest or turning sharply under power. The latest Michelins are much better on wet road grip than they used to be and the car is much more controllable in consequence.

   Hard linings are used for the ventilated disc brakes and we noticed much better pedal response when the had warmed up. With cold linings it took 80 lb effort to record just over 1g from 30 mph, but after completing the fade tests we found a better stop could be obtained with only 60 lb effort. There were fluctuations in the response during our 10 stops from 70 mph at 0.5g, but overall the fade was negligible. These thermal characteristics showed up on the road as well, the feel of the pedal usually being much more reassuring when the car was being driven hard under give-and-take conditions.

 

Fittings and Equipment

   As already mentioned, lightweight competition-style seats are fitted instead of the more luxurious normal coupe type and these gave all our testers exceptionally good hip-hugging support. There is a hard edge which makes climbing in and out more difficult, but once settled in they hold driver and front passenger securely against all cornering forces. Under the front edge is a deep soft bolster which gives good tight support, but those short in the upper leg found it had to be compressed when operating the clutch.

   Although these seats slide back and forth on runners, they can only be adjusted for rake by undoing bolts at front or back with a spanner and resetting the angle of the whole seat. The steering column is fixed and seems too high, especially when fitted with the standard 16.5in. dia. Wheel.

   These snags apart, the driving position is good with a fine view out all round and no blind spots. The interior rear view mirror is supplemented by a very useful door mirror, slightly tinted to reduce dazzle at night. Rear seats are shaped for two only with a folding centre armrest and rather restricted legroom. The BMW coupe is 3in. shorter in the wheelbase than the six-cylinder saloon and is not intended to be a full four-seater.

   In front of the driver is a hooded binnacle housing four circular dials. On the extreme left is a combination gauge incorporating fuel level, thermometer and warning tell-tales for oil pressure, generator charge, low fuel and headlamp main beam. In the centre are the rev counter and speedometer, the latter reading to 150 mph and incorporating a total mileage recorder and trip mileometer with rather fiddly reset knob under the facia. On the right is a clock. There is no oil pressure gauge or ammeter.

   Switches are well separated, with the main lighting knob on the right and two stalks on the steering column taking care of indicators, headlamp flasher, dipswitch, wipers and washers. A three-position pull-up knob on the left of the gearlever slects intermittent action (about 5sec between sweeps), slow or fast wipe. Pulling the indicator lever towards the wheel rim squirts powerful washers and starts the wipers which continue for three sweeps after the water has stopped squirting, to dry the screen.

   Heater controls are grouped in the centre console, above an adjustable fresh-air duct. Temperature control is by progressive air blending and the booster fan, which also provides forced ventilation, has three speeds. An electrically heated backlight is standard.

   Front and rear windows have electric lifts, operated by double acting switches on a small panel around the gearlever. The circuits are wired through the ignition and the motors work slowly, especially when the windows are wet with rain. An unusual feature for these days are front swivelling quarter-lights, opened by hand-wheels in the trim pads.

 

Living with the CSL

   The car used for particular test was actually on a six-month loan and will be the subject of a 10,000-mile-long-term appraisal later. Much more will be included then on how the car behaved in regular use and how one “owner” got on with it day after day.

   Due to the relative value of pound versus Deutschmark, the CSL has risen by about £1,000 since the beginning of this year and to put one on the road now, excluding insurance, would cost close to £7,500. That is a big increase over the £5,828 being asked for the CSi in 1972 and makes the CSL more expensive than an Aston Martin (with six-cylinder engine), a Jensen Interceptor, a Mercedes-Benz 350 SL or a Porsche Carrera RS. For this extraordinarily high price you get a shape which has been around for several years and performance (as the comparisons show) is not exactly in the ultimate class.

   Ignoring, for the moment, the price tag, the CSL is a well-built car which gives a lot of satisfaction to the driver and covers long distances with contemptuous ease. Like the first cost though, servicing and maintenance charges are high and the price of spares after the six-months warranty period is creeping up almost day by day.

   One very impressive feature of the 3-litre BMW range is the comprehensive tool kit fitted to a drop-down case inside the boot lid. With the aid of this and the very explicit handbook routine servicing can be carried out by a technically minded owner, although electronic diagnostic equipment is needed to tune the engine properly.

   Because of the car’s low waistline, the boot is rather shallow, particularly as the spare wheel and fuel tank are mounted under the floor. It is wide and long, however, with a useful bin for oddments on the right and the jack clamped alongside the spare wheel. A fitted carpet covers the removable plywood floor.

   Inside the car there is a lot of stowage space, with a drop-down glove locker in front of the passenger, a central cavity under the radio and map pockets in each front door. Lady passengers particularly liked the wide shelf across the top of the facia which takes a handbag or guide-book so easily.

   Under the front-hinged bonnet routine checking of levels is easy, but the oil filler is on the opposite side from the dip-stick. The distributor is especially accessible and very simple to adjust.

 

Conclusions

   As a compact 3-litre coupé with elegant styling, refined running and exceptionally quick acceleration, the CSL is hard to match. It has delightful road manners and draws admiring glances wherever it goes. At the latest price though, which is entirely the fault of the importers (although it is listed in Germany at the equivalent of only £5,400), it has to square up to some formidable opposition and against these it suddenly seems over-priced. Maybe when our Government allows realistic increases from the home manufacturers, the status quo will be restored and we will be more enthusiastic again towards this BMW. At the moment we judge it a very fine car indeed, but too expensive for what it offers.