From: "Unbeatable BMW", by Jeremy Walton, © 1979, Osprey Publishing Limited.
THE BIG BMW THAT WOULDNT LIE DOWN
A competition car is usually obsolete by the time it is winning. The designer is already firmly launched into drawing up its successor. Such statements apply, most of all, to grand prix cars, but even in touring and other kinds of production racing, it is rare to see a basic shape cling on for much beyond four seasons. Yet the big BMW coupés (which trace their shape back to the 1965 2-litre coupé by Karmann) raced internationally from 1969 to 1978, when the "Big Bimmer" was still capable of winning. In fact, it has even won its fifth European Touring Car Championship.
Of course, the BMW coupé changed dramatically during its long reign. The basic road car design reflected this competition success accurately. BMW could not fulfill their ambitions without preparing a lighter, high-performance version (the CSL), finally meeting with full success when that model was homologated and then sold with a full set of "wings". Nicknamed "Batmobile", this car, with its addition of eight-part aerodynamic aids, so infuriated the German transport authorities that BMW had to resort to packing them (the wings) all away in the boot when the car went on sale in its native country!
As a road car, the history of the coupé is well worth an outline to put the racing versions performance and achievements into perspective. In 1965, the coupé was sold either with a 100 bhp, 2-litre engine or with the twin carburetter, 2000 Ti unit (the 2000 CS; CS for Coupé Sport). By October 1968, BMW had recovered far enough in their companys fortunes to be able to announce their return to the luxury car market, a sector they had been forced to ignore for years. The big saloons, the 2500 and 2800, attracted most attention, but at the same time German taste for coupés was fed by the offering of a curburated, 170 bhp, 2800 CS model. This lost the distinctive one-piece headlamp glass covering of the 2-litre model, and carried a strong family identity with the new six-cylinder saloons, having clearly defined quadruple headlamps and other minor styling changes to suit its new status. The next big step in the road cars life came with the adoption of the 3-litre engine. The extra 200 cc (approx.) came from the use of an 89 mm bore in place of 86 mm, the stroke remaining at 80 mm, for 2985 cc. Power was then quoted at 180 bhp, but a little later came the adoption of Bosch electronic fuel injection (the car which would be called the CSi) to replace the twin down-draught Solexes used previously. By that stage, the engine was producing 200 nett bhp and the car actually needed the all-round ventilated disc brakes, which were announced with the 3-litre carburated engine. In 1972, BMW produced the first of their CSL lightweight derivatives (production actually started in May 1972), which offered an aluminium bonnet, boot and doors with little in the way of luxury equipment. To qualify the car for racing in the over-3-litre division (reboring was limited to a fixed percentage in Group 2) the capacity was quoted as 3003 cc (89.25 x 80 mm!), a strange bore figure that was retained in conjunction with an 84 mm stroke to provide 3153 cc when the 1973 winged version was launched. In road form, this allowed 206 bhp at 5600 rpm, which provides a pointed comparison with the original 100 bhp back in 1965.
The rebored six-cylinder was the most powerful offered to coupé road customers in a production run from 1968 to 1976. The CSL label needed only 1000 cars to pass it as far as the factory were concerned for homologation purposes.
In the aftermath of the 1973/74 fuel crisis, when the last of these cars were being made and sold, they dropped to ridiculously low prices along with some other secondhand six-cylinder BMWs as people panicked about fuel economy. Today, the CSL can rightly be regarded as a limited edition classic, but it was always almost impossible to define the car unless it had the full wing regalia and the (nominally) 3.2-litre engine. It was always called the 3.0 CSL, whatever the capacity. I drove a very early orange 3.0 CSL in May 1972 which was fitted with Solex carburetters, and there was no mention of the "oversize" engine. The concessionaires in Britain went on to offer their own 500 versions of the CSL with fuel injection only, and with a lot more luxury equipment than was offered in Germany. The 3003 cc capacity was really a maximum rebore size, rather like the nominal 1601 cc credited to the Ford Escort RS1600 when it appeared. Ford, in fact, belatedly countered the CSL through the 1973/74 winter with an RS3100 Capri which they needed to enable them to race the Cosworth 3.4-litre engine in 1974, and which also carried a tail spoiler; by that time BMW had made their point about aerodynamics! One could say that the six-cylinder BMW took the established BMW principles and expanded on them. Trailing arm rear suspension, MacPherson strut front suspension, and a single overhead camshaft engine (which was very much the six-cylinder version of the existing four), made the car a tempting proposition to the tuners from the start, and it was the German competition-orientated companies that gave the six-cylinder its early success, along with the factory. The factory was engaged in racing the 2002 in 1968/69 and concentrated heavily on Formula 2 in 1970 a category they had been contesting since 1967. So there was not enough manpower available to do much about the six-cylinder model. Besides, its big drawback was always its weight for the seize of its engine.
Such a state of affairs was just asking for someone to show a little private enterprise, and it came from Alpina in the weeks leading up to the July Spa-Francorchamps 24-hour race of 1969. That was when the big BMW made its debut in racing. Comparatively unmodified, it did not set the competition world on its ear, not even the parochial saloon car racing scene. Who knew then that this was the car that was to win in categories varying from Group 1 (production) to the wildly modified exotica that raced in Group 5? That one day the floorpan would glow with the heat of an engine capable of generating over 750 bhp turbocharged horsepower from 3.5 litres? That it would go on winning for four years after production of the CSL had ceased, and even after the factory had replaced the 3.0 CS range by their then new 633 CSi flagship for the BMW buyer of 1976? Or even that the factory would compete with an obsolete model for a season? That is almost unheard of, yet BMW did it and the big BMW took it all. It was not without complaint, however, because you cannot just install 750 or more bhp at one end and expect to get power laid effectively on the tarmac at the other, via a suspension and weight distribution system which had previously been designed for about half that figure!
So, when Burkard Bovensiepen and his Alpina staff recall the time they gave the six-cylinder coupé its rugged competition debut in a twenty-four-hour race, they smile a little. The car was so standard that it used the normal 6-inch by 14-inch diameter wheels, power steering, and relied on barely modified suspension with production brakes, and so on. Alpina had taken the engine apart, blue-printed it and substituted triple twin-choke Weber carburetters as they reassembled it, claiming 250 bhp for the fenderless coupé.
In spite of consuming some forty Dunlop racing tyres in the 24-hours, the alloy-wheeled BMW 2800 CS did complete the course, as it did on other epic racing performances later. Technically speaking, Alpina were far too busy racing the 1602 and 2002 to progress much further with the six-cylinder car during the 1969 racing season.
In 1970, interest in the car increased sharply, and BMW asked Alpina to represent their interests in saloon car racing while the factory pursued their hefty Formula 2 schedule. Alpinas work during the intervening winter saw the car beginning to take its first steps toward racing saloon from converted road car. Plastic wheelarch extensions covered wider alloy racing wheels, but still the brakes and suspension remained virtually unmodified. The engine progressed, and one great aid to reliability with the wet sump lubrication then used (and subsequently required for the 1977 season) was Bovensiepens patented pistin displacement pump. This long auxiliary cylinder contained a piston and an emergency supply of oil; when the car was braking heavily or cornering hard, the long six-cylinders sump would inevitably swill its oil everywhere but where the oil pump could pick it up. The fact that the pump was picking up air rather than oil would be relayed to the auxiliary cylinder. Because of the change in air pressure within the auxiliary cylinder, the piston would be activated, pressurizing a relief supply of oil to feed the starved engine bearings until the engine pump could again pick up oil instead of air. Then the piston inside the auxiliary cylinder would return to its normal position. Such a system was not the complete answer to the lubrication problems of a wet-sump, six-cylinder engine under racing conditions, when the oil pressure is particularly hard to maintain. However, it was enough to allow such engines to survive. The same principles were needed when international Group 2 touring car regulations were altered to demand wet-sump lubrication again in 1976 (dry-sump lubrication had been used in the intervening period). In 1977, when Broadspeed took the Jaguar XJ 5.3 C V12 coupés European Touring car Championship racing, Bovensiepen very generously supplied a pair of his auxiliary piston displacement pumps to try and solve the British cars enourmous wet-sump lubrication problems. It helped, but the problem was a lot bigger on the Jaguar.
Based on race results, the 1970 season was the beginning of the CS success story, for Alpina had outright wins in two internationals counting towards the European title. This, in return, created interest in making the 2800 CS really competitive, both at the factory, where Gerhard Haerle was in charge of making sure the drivers were paid by BMW, and amongst other tuners. Down at Freilassing, Josef Schnitzer and brothers had started work on the sixes. Charley Schnitzer recounts that they competed "in a few small sprints and national races, where we got a few small wins". As always, Schnitzer produced a pretty powerful engine for the car, and progress was so encouraging that they entered their smart CS for its first European Championship race at the nearby Salzburgring, just over the border in Austria, in the spring of 1971.
Meanwhile big things were happening chez Alpina in 1971, too. In March of that year, Dr Fritz Indra arrived at Buchloe. Born in Vienna, a graduate of technical high school in Germany, "Fritzy" was a fair, curly-haired youngster tackling his first full-time job in automotive engineering. However, he had an honourable background both in competition and emission control work both subjects that needed attention at Alpina. Emission control for a "tuner" in 1971? Yes, for the German transport authorities, through their tough TÜV board of control, could legally insist that cars comply with comparatively stern construction regulations. This particularly affected people like Alpina, who made modifications to existing cars, as one had to have these additions tested and inspected by the TÜV before a customer could legally use the extra equipment on the road. This applies in an even more extreme form to this day, and has meant that the speed equipment industry in Germany has grown up with the requirement that their products should pass rigorous tests; in most cases, these tests are just as thorough as the original manufacturer trials. Thus, though he is best known for his work with Alpina on the race-track, Fritz Indra and his irreverent sense of humour were also vital in making sure that Alpina could legally sell a growing amount of performance equipment. It is also relevant to note that at this time Alpina business was changing the nature of its work. It had started as a business which could supply parts cheaply so that a customer could fit them and then even afford to go racing. Today, the racing business is so sophisticated, and so many parts and facilities are needed to convert a touring car into a racing car, that the earlier kind of competition work for customers is increasingly rare. Instead, they tend either to convert an increasing number of complete cars, or to build them from scratch, neither of which would have been possible without the engineering attention that has been applied to meeting the federal governements requirements.
Bovensiepen always used to joke that all his drivers were Austrian, and with the arrival of Indra, the Austrian atmosphere grew even stronger. To intensify this, Dr Indra had been involved with Niki Lauda and even Jochen Rindt in Formula Vee during a spell at Karmann, and he had thoroughly enjoyed the intense competition then prevailing in this single-seater class. Racing most weekends as a practical scientist had obviously taught him a lot about car behaviour, but it left him rather unprepared for touring car racing.
"When I come to Alpina, these cars are terrible; just like normal saloon cars, only the instruments and seats seem to be changed!" He laughs without fear and says, "the 2800 CS had won at Spa, of course, but it has the same disc brakes fitted, power steering. Everything is production compared with the Capris. It had 13-inch diameter wheels [because you could get better rubber from Dunlop and to lower the centre of gravity JW[ and the engine has 280 horsepower with the three Webers, but the car is so heavy, you just cannot imagine.
Braungart and Neerpasch at Cologne they make a proper racing car. It was so completely new for us in Germany; the Capri had these big wheels, light homologation weight, racing suspension. They were so much faster than our cars then, maybe ten to fifteen seconds each lap at the Nurburgring.
I remember a week or two after I arrived, we had to go to Monza for the first round of the European Championship, with three coupés and four 2002s!" Though it was obviously going to be tough to get any kind of results with such a large team and only four mechanics, they set to work on the big coupé as their priority. On the suspension side, eight-inch-wide alloy racing wheels and new competition shock absorbers were installed, which could all be done quite rapidly. In the longer term, Indra knew they had an engine problem, "you could go to 7000 rpm, OK. Then go 7100 rpm and the crankshaft is broken!" To overcome the torsional vibration that was inflicting such havoc, Indra decided to turn to the expert services of Freudenberg, specialist German consultants, on questions of torsional stress. They tested the crankshaft and recommended a succesfull solution; machining away 8 kg.
At the factory, von Falkenhausen and his engineers were meant to be primarily concerned with production car problems, for the directors had ordered the withdrawal of the company from direct racing participation at the close of 1970. However, with men like von Falkenhausen and Rosche around, there was little chance that all such work would miraculously cease. Von Falkenhausen remembers encountering the same crankshaft problem, but tackling it by different methods to achieve a reliable 7500 rpm when using the 2-valve, six-cylinder motor. They installed both a lightweight flywheel and clutch, plus specially developed crankshaft counterweights. There were the same number as on the production engine (twelve, in total), but they were smaller and lighter.
The factorys role was more of a watching brief through the 1971 season, though they drew little comfort from watching the blue and white V6 Capris lapping up race after race. Gradually a resolve was growing to do something about the situation, but through 1971 itself, the competition limelight on the big coupés was carried entirely by the tuners. Just how seriously BMW took the situation can be judged by the fact that they commissioned a British racing saloon car preparation specialist to complete a design study on the coupé at the close of the season. They also made sure that the 3-litre coupé (3.0 CSi) was homologated for racing in July 1971.
Meanwhile, back at Alpina, the factorys attitude to homologation was: "You dont need any, the car is perfect". In other words, policy at the time was very similar to Bovensiepens own inclination and Neerpaschs consistently held views on Group1; the less modification and consequent easier homologation the better. In 1971, Burkard still felt that big brakes and other radical modifications were not a good thing -he felt that the car should just be reliable and finish with honour but others (Indra amongst them) wanted to win against the accursed Fords.
Still more power was needed. The leightweight CSL was still a future plan, a dream that the tuners kept asking for, but one that the factory refused to homologate untill Neerpasch arrived. Thus work began on fuel injection at Alpina. The big six-cylinder was sold to the public with a fine Bosch electronic system later in 1971, but for racing the mechanical Kugelfischer layout was required. Kugelfischer injection had been used by the factory for many seasons on the four-cylinder, but for the six-cylinder, Alpina enlisted the help of Herr Quast, making use of the special leightweight pump that they had made reliable after experience with the four-cylinder factory engines.
At first, fuel injection did not yield the test bed results they had expected. Dr Indra was amazed at the time: "at first there was no power, or no more than for the carburetters. We look on the test bed, and think this is impossible. Then we make new injection trumpet lengths and modify the combustion chambers to suit the injection. Then we get more power". These remarks applied almost equally to the four- and six-cylinder Alpina cars then being raced.
Using 3-litre engines on carburetters, Alpina found that power outputs were always below 300 bhp (Schnitzer claimed 295 for theirs), but once those internal and external injection changes had been made they were eventually able to realize 330 bhp. Indra, and Dieter Quester for that matter, well remember the debut of the six-cylinder injection system on an Alpina coupé. It was at the Nurnburgring 6-hours of 1971, and the original layout featured an enormous "guillotine" slide to admit or close off the air supply to the six chokes, which had no bearings to ease the slide operation. Naturally this meant the throttle operation was very heavy and the linkage was subject to great stress. The unfortunate Bovensiepen was struggling to solder the linkage together for Quester up until ten minutes befor the start. They did finally weld it together, but the linkage fell apart in "about half a lap", says Indra.
The advent of more power for the car produced other problems. Tyres, brakes and suspension were all found to be inadequate, though by this time the disc brakes had been slightly thickened for competition to absorb a little more heat; standard calipers were retained. This was an enormous disadvantage compared with their rivals at Ford, as were the car weights, which were roughly 970 kg for the Capri (then offering about 300 bhp) and a whopping 1270 kg for the BMW. No wonder they were beseeching the factory for a lightweight model!
Some of the transmission problems apparent in 1969 were solved not long afterwards. For example, the differential had been overheating, and Alpina developed their own ingenious external pump to defeat this. The gearbox also gave trouble, and a five-speed ZF was adopted virtually "from the start". However, in Indras words, "we still had standard clutches, and the drivers were not allowed to use full power for the starts!"
An item that is still sold today from Alpinas rural Buchloe premises was developed during the dour struggle of the 1971 racing season, when, in Indras words, "we worked all night, every night, trying to beat the Capris". These were harder bushes for the suspension, front and rear. Such a substitution, in which the softer rubber that allows a quieter ride is sacrificed for stiffer bush location of all the suspension components in the interest of greater driver control and "feel", was commonplace even on tuned British road cars of the period. In Germany, the harder bushes were initially held in some suspicion as it was thought they would be liable to break. When this proved not to be the case, such bushes became a traditional feature of BMW preparation, too. At this stage rim sizes averaged 8 by 13-inch front and 9 by 13-inch raer, and servo-assisted power braking was still retained. However, the power steering had gone and the big BMWs were showing a turn of speed in a straight line that emphasized how competitive they would be if a leightweight chassis could be swiftly sorted out.
The 3.0 CS by Schnitzer had the honour of showing the Capris home for the first time in 1971. Appropiately it was driven by Dieter Quester, who did the damage (at the fast Zandvoort circuit in Holland) to the Capris invincible reputation. Nose spoilers were now beginning to appear on BMWs; the Capris, however, had needed such nose downforce help on their long snouts since 1970.
At the close of the 1971 season, Alpina were not too pleased with themselves. It was obvious that the 3.0 CSi would become the spearhead of a new BMW assault on Fords monotonous success, but it was not obvious how BMW were going to do it. For the time being they seemed content to rely on the tuners to turn their prestige model into a winner; but which tuner would get the lions share of the factory blessing?
BMW, themselves, had not made up their minds. As the racing season closed with the one Schnitzer victory, they decided to see what could be done by an independent consultant. Accordingly, Southam in Warwickshire became the mecca for representatives of BMW Concessionaires (GB) planning a new image for the Cooper Car Company, which they had acquired. Southam is the home of Broadspeed, headed by Ralph Broad, the bespectacled ex-Brummie who talks a little faster than a Thompson sub-machine gun in full flow. Ralph had been murdering the opposition in Britain and Europe with his versions of the Cosworth BDA-propelled Escort (before that he had prepared Anglias and Minis, driving the latter as well), and he was looking for something capable of winning outright. So were BMW.
The result was the provision of two works prototype very lightweight bodies. These were made using the lighter gauge steel and aluminium bonnet, boot and doors that were to become the CSL specification later on. There were no wings then, but Ralph did fabricate his own alloy front spoiler and the car carried massive (for the time) wheel-arch extensions in glass-fibre to cover 11-inch-wide front wheels and 13-inch-wide rears. Because Dunlop were able to supply the first of their ultra-low-profile touring car tyres for the 1972 season, Broadspeed opted (along with Ford and Schnitzer) to run 15-inch-diameter wheels. This allowed bigger brakes to be installed, as well as taking advantage of better rubber.
Some Alpina and Schnitzer know-how was used in the Broadspeed coupé, including a pristine Kugelfischer-injected engine that had passed through the hands of Paul Rosche at BMW. This motor was claimed to give 332 bhp at 7500 rpm with a limit of 8200 rpm. With the assorted cooling pumps Broadspeed built in for the ZF gearbox and limited slip differential, it proved reliable through a hard two-hour thrash in the snow of Salzburgring in April 1972, but the car did not race again. Though it finished third in the hands of John Fitzpatrick in the falling snow, it had been too advanced in specification. Scrutineers made Broad and the mechanics take off the aluminium body panels which were not homologated prior to the race and there was a great deal of general suspicion about the cars eligibility to race under Group 2 rules. The truth was that it anticipated by nearly a year how things would be when the CSL was built, but it needed the arrival of Neerpasch and Braungart at Munich to pull all tuners and their own efforts together for a concerted effort.
The Broadspeed car had technical significance. I was privileged to drive the car one afternoon around Silverstone Club circuit when Niki Lauda also tried it for a few laps. I thought it handled and stopped quite nicely, but it needed a professional like Lauda to really get the best out of the car. He had a valid base for comparison too, for he was driving the Alpina car occasionally in the 1972 season, and confirmed that Broads variable-rate Bilstein suspension was a lot less twitchy than he found on the Alpina coupé. To be fair, the tracks Lauda had appeared on in the Alpina car were a lot rougher than Silverstone. Ride quality was of some importance in European long-distance events.
Lauda was also appearing that year in a March 722 and he said of Broadspeeds coupé, with typical dry humour, "its almost as good as my Formula 2 car!" This was not altogether surprising for, as part of his development programme after Salzburgring, Ralph Broad altered the rear centre of gravity quite radically by lifting the rear floorpan three inches, lowering the car appropirately and allowing the rear wheels far less camber change under varying throttle and cornering conditions. The car also used solid metal jointed suspension instead of rubber bushes, hollow tube aluminium anti-roll bars with 10.9 inch diameter Lockheed discs, and servo-assisted front brakes carrying four-piston calipers. I believe all these items were all returned to Munich.
Meanwhile Alpina trod their own lonely path. For 1972 they ran regularly with 310/320 bhp, and these cars were what Indra describes as "Alpinas first racing cars". Having only one coupé to concentrate upon, they tried some fairly advanced ideas. The disc brakes (with unventilated rotors) were mounted inboard and could be considerably larger than before, matching the units with the 14-inch-diameter wheels that had replaced their 13-inch-diameter units. A titanium flange to replace the production UJ was mounted between the propeller shaft and the differential, and solid rubber blocks were installed to mount the differential to the rear subframe. Alpina also shifted the driver back nearly four inches and the engine rearward by almost two inches, but their biggest problems were the wheels they had choosen, for they were simply not putting enough rubber on the road.
Again the only BMW victory of the year came from Schnitzer, with that superbly turned out silver and red machine taking the pounding handed out by the home track at Nurnburgring in its stride, and winning the 6-hours. Since this was shortly after Neerpasch joined BMW, it seemed a little bit as if it had been ordained, but the truth was the Schnitzer car was tremendously fast (some 360 bhp was claimed and rivals were almost inclined to believe it) and running on the proper rubber and brakes. It was also driven by the experienced trio of Rolf Stommelen, John Fitzpatrick and Hans Heyer on this occasion. For Alpina and Schnitzer, winning races was all-important, as BMW had offered a substantial 10,000 DM to the winner of a European Championships round in a Munich machine, and 100,000 DM if either could win the title!
That was to prove impossible against the Capris, since the Fords won the title for the first time since the Cortina in 1965; ever since then class-winning cars such as Minis and Alfa Romeos had won the ECT marque series outright, although BMW had class victories.
The days of easy winning were coming to an end for Ford though. Alpina, Schnitzer, GS Tuning, Koepchen, Broadspeed and BMW themselves all agreed on the need for a lightweight coupé. The prototypes were already running around outside the Karmann works at Osnabruck.
Neerpasch and Braungart were installed and operational from Munich in May 1972, Braungart having left Ford on just a months notice. The ex-Ford duo had a year to produce a winning BMW in the European Touring Car Championship. BMW, like Porsche and Mercedes, cannot countenance losing, which is one of the reasons why we never see these prestige names in the German motor industry slugging it out in the same category.
Swiftly they took the decision to go ahead with the lightweight project, which was already well under way from a roadgoing viewpoint. Indeed, Neerpasch had a lemon yellow CSL, complete with its distinctive alloy "spats" at Salzburgring in April. As he had only just announced his decision to leave Ford it was little surprise to see that some kind souls from the rival Ford team had left a neat "Powered by Ford" sticker under the BMW chrome nomenclature while it was parked outside the hotel.
Neither Braungart nor Neerpasch had much time for smiling about such pranks. As Braungart quietlt revealed in an interview some years later, "there were the rally people doing their own thing in one corner at Preussenstrasse, and there was almost no development time. There was an engineer to do some drawing and me we knew Paul Rosche would look after the engines. In four months we had drawn everything and ordered it to be made; new front suspension, steel hubs, new castings for the MacPherson struts and centre locking for the wheels (just one large nut and hub pegs secure the racing wheel, making changes faster and location better); completely new steel trailing arms to accommodate much bigger wheels; a complete power train (a Getrag five-speed gearbox was homologated and replaced the ZF) from one end of the car to the other. We even had a new propshaft made, and some other axle ratios, magnesium castings for the bell-housing and the gearbox and several cooling systems. We had the belt-driven oil pump from the flange of the driveshaft for the differential with the pulley built into the inner driveshaft flange." The brakes were also new, after co-operation with Ate.
Rosche was certainly getting on with his side of things, too. A dry sump 92 x 80 mm, 3.3-litre version of the six-cylinder was devised and homologated ready for use with the rest of the competition CSL on 1 January 1973. And his M52 engine still retained the thirty-degree slant which caused the oil to run up the bores in pre-dry-sump days, producing some 350 bhp fed by the usual Kugelfischer system.
At the time manufacturers could only bore out their engines for Group 2, the stroke having to remain as homologated; one of the reasons Schnitzer always seemed to have an edge over the others was by virtue of a little extra daring in over-boring. Rivals inside and outside the BMW ranks always pointed the finger of suspicion at Schnitzer on this count, but no irregularity was ever established. Oddly enough, when Alpina came to run at the first race of 1973 they had not got the homologated parts to make an "over-3-litre" engine, and Neerpasch chose this meeting to investigate. It was a surprise for the factory to find that the victorious Alpina car was under size.
Ironically Martin Braungart could not give the car its first test runs at the then recently opened BMW proving ground outside Munich the authorities said it would be "too noisy"! Braungart was able to drive the car up and down a runway at Dorniers airfield. That was before Christmas 1972, and Hezemans was able to drive the car at Hockenheim soon afterwards. Through that 1972/73 winter they kept plugging away at the testing, with help also coming from Hans Stuck.
The white cars with their red and blue BMW Motorsport corporate stripes carried full-width front spoilers, which had cold-air ducting for the large four-piston, alloy-caliper disc brakes fitted inside those large-diameter BBS alloy composite wheels. Rim widths were fixed at eleven and a half inches at the front, and thirteen inches for the rear, using at that time the Dunlop rubber they were to stay with until 1976. The replacement trailing arms had been necessary tom accommodate a large set on rim width and for wide wheels to fit beneath wing extensions.
The factory racing coupé had covered some twelve hours testing at Monza, scene of the first round of the European Touring Car Championship. BMWs sport division arrived feeling in good shape. The cars had run excellent pre-practice times and the only real problem they had experienced in the pre-event testing was some cracking of the new steel hubs. There was apparently no danger of losing the wheel altogether, but a change in material specification was called for.
Braungart smiles wryly at the memory of what happened in Italy that Sunday, when both cars were eliminated by dissimilar engine failures. "Its always the same: after ten years you know the truth competition is completely different to testing". They made no major changes to the engine specification at that stage, though the six-cylinder did feature special sealing rings around the combustion chambers that were located into grooving on the top face of the cylinder block, and the tolerances were tightened up. They had engine trouble in the second round at Salzburgring too. Even though it was pure bad luck, Rosche was just beginning to get edgy enough to guarantee that he would personally inspect every componant that went into the works engines in future, when a lift came with their first win in the German Championship. "We were racing to win in Europe, but any win is always good for morale", Braungart recorded. Technically speaking, there was still in-team scepticism about the engines, so Neerpasch and Braungart directed them into the longest and most public test they could find: Le Mans.
As Braungart felt afterwards, "it was a big break to finish and beat the Fords". Mechanically speaking the engines were fine, but the first of many gearbox problems on the car driven by Stuck reared its head. Even five years afterwards Braungart admitted that they were not really sure what had gone wrong, and what kept going wrong, on this car. "In theory the gearbox was perfect. It had wider gears, bigger bearings and a different lubrication system. Do you know, in twelve months we made thirty modifications?"
The team went back to an aluminium casing for the gearbox. Despite work with Ate, the German braking specialists, to solve a very visible problem in night racing, the brakes were glowing red through the wheels and the pads needed changing every four or five hours, a swine of a job with the heat generated. Ate attached cooling fins to the calipers, and the design of the four-piston calipers lives on in the 320 Group 5 cars. Ford also picked up the idea for their Capris, and there was only one really competitive BMW that occasionally appeared in Europe without them. This was Brian Muir' Alpina CSL, which used Lockheed components and was intended primarely for the last 1973 season of Group 2 racing to be held in Britain. Otherwise the Muir car was a twin to the one Alpina were campaigning in Europe, which won the opening round of the series after both the works cars and the Capris broke.
Aside from the evoluation normal to a developing racing car, there was a revolution hidden and awaiting a startled touring car racing world, a potential upheaval that dated virtually from the moment Neerpasch and Braungart started their Munich crusade to beat their old team-mates in the North. They had spotted an amendment in the International FIA regulations that permitted evolutionary changes to be added to existing models. They decided this meant they could offer the CSL for sale with a full aerodynamic wing set. Braungart relived the decision for me as follows: "We just had no time to do anything. The next homologation date we could meet (and after which they could use the optional equipment without fear of retaliation from Ford) was 1 July, and we had to get the papers into the FIA about six weeks before that.
There was no time for a normal production development programme. We took a racing CSL to the wind tunnel at Stuttgart and we really just tried the effect of sticking on all sorts of wings, spoilers, and so on. The styling department had helped us with some ideas, but it was all such a fast job that we just tried to see what we could find that was best. Our problem was to get more downforce on the back of the car, and we had about two days to find the answer with the wind tunnel.
The standard car had rear end lift of about 60 kg at 200 km/h (some 124 mph) and we worked until we had converted this lift into 30 kg extra downforce upon the back. I remember Hans Stuck showed how little downforce we had before on the rear he went off at the Nurnburgring 1000 km when he blistered the rear tyres by sliding so much; he ended up in the armco!" Braungart looked suitably amused, but the first test with the wings was to provide even more dramatic proof of their effectiveness.
The team had competed in six evenmts with varied success and was testing at the Nurburgring 22.7 kilometre / 14.2-mile Nordschleife, a week before that circuits 6-hour European Championship qualifier was due to be held. A 3.3-litre six was installed (by this time producing over 360 bhp) and they were lapping in the 8.30 bracket; earlier in the year Jochen Mass had managed an 8.25 lap in the 2.9-litre Capri. Because time was short, the Motorsport mechanics were asked just to fit the slightly larger front spoiler and the tail wing. The BMW "Batmobile" in Stucks hands immediately recorded 8.15,4. Nearly fifteen seconds a lap! It was a team managers dream come true, and Ford could not homologate an answer that season. "Forget the splitters on the front wings and the hoop over the rear window", Braungart told me recently, "they show a small percentage improvement in the wind tunnel, but you cannot see this in the lap times".
But the effect of the wings was not just one of boosting lap speeds. A number of chassis problems could then be solved quite quickly. Apart from the tyre problems recounted in Stuck' case -which disappeared, since the cars were no longer excessively tail-happy the winged BMW could generally run softer springs than the Capris.
In general, as a competition car is developed, the spring rates tend to go up with the lap speeds. The faster the track, the better the car worked, for it was literally pressed harder to the road, due to the efficient aerodynamics of the front and rear spoiler.
Rosche also added his own brand of engine magic to the BMW cause, producing a 3.5-litre version of the faithful SOHC alloy 12-valve head, iron-block six. Rosche grinned widely when recalling the details, for at the time they were a little worried about going to anything more than 90 mm on the bores as there was not sufficient space left between the cylinders to allow water passages. "Now we have it on the road cars", he chuckled happily. That reminded me forcibly how much BMW benefit from the personal competition experience of Rosche and others like him. (Later, the M1 mid-engine coupé for the road was to draw extensively on the knowledge acquired with the big, front-engined CSLs.) The finished result measured 3498 cc from a bore and stroke of 94 x 84 mm. Using the normal competition compression ratio of 11:1, this allowed "a lot more torque" and 370 bhp at 8000 rpm. The torque was important, for the CSL was still considerably heavier than the Capri, racing at around 1062 kg. Set against that, the BMW engines gave approximately another fifty bhp, for the Weslake-headed Ford V6 was really at the end of its life and was safest at 320/325 bhp from nearly 3 litres.
In theory, and on the track, the 3.5-litre engines and wing system were enough to slaughter the Ford opposition with an unbroken string of wins. It would be wrong to think they were all BMW wins though, for the role of Alpina and Schnitzer was often the leading one, if the factory struck trouble. In fact, Alpina still say that they could have won the Championship, and beaten Ford on points, without the factory points, for they won quite a few rounds (notably the first and an epic struggle at Silverstone) and finished every race excpt the Spa 24-hours, where the tragedy of young Hans-Peter Joistens death overshadowed the importance of completing a motor race.
Technically, Alpina went for a simpler car than the works. They abandoned the magnesium transmission castings, retaining the 15-inch-diameter wheels and Dunlop tyres when the works and Ford had started working with the new 16-inch-diameter wheels. (Schnitzer used large-diameter wheels with Firestone tyres.) They installed production type struts and uprated them appropiately rather than using the full-race and purpose-built factory struts. The latter move was to try and make the steering lighter and more manageable in some of the longer distance events. Alpina also reverted the rear disc arrangement to a conventional outboard mounting point from the previous years inboard experiments.
The engine specification was conservative too. For the first race they had to run the smaller engine (3 litres), and even when they had the full 3.5 litres they reckoned to run up to twenty bhp less than Schnitzer in the interests of making the maximum number of race finishes, an objective they achieved. According to their tests this means they had about 360 bhp at best, using narrower rims than most with ten inches at front, eleven at the rear. Alpina experience in 24-hour racing was excellent, with three Nurburgring night and day races to their credit; part of this was due to having relieved the engine of a little compression pressure, knocking back the ratio from 11:1 to 10,5:1. Deliberately, the emphasis was placed on torque, and they had 275 lb ft (= 38,0 kgm) or more at 5000 rpm, the engine pulling well from that point to the bhp peak of 7400 rpm.
Alpina worked on trying to move as much weight as possible to the rear. One unsuccessful move was to mount the water radiator at the rear, but it was both too big and too vulnerable to assaults from both the ground and the rear, which are not unknown in saloon car racing. However, weight distribution was improved a little by installing the flat petrol tank. The dry sump oil tank was placed within the boot from July 1972 onwards, when it was first adopted.
Alpinas biggest problem during the year was to replace Hans-Peter Joisten, the driver Lauda had chosen to partner whenever possible until his death in a multiple pile-up at Spa-Francorchamps. Lauda was becoming increasingly involved in Formula 1, and Bucjloe used all sorts of people during the year. At Paul Ricard in 1972 they had appalling luck, with Gerold Pankl injuring a spectator and retiring on the spot. They used a fabulous pairing once in 1973; James Hunt / Jackie Ickx. Brian Muir did a lot of Trojan work for them and Derek Bell put in heroic drive with Harald Ertl at Silverstone, but more on that later.
For 1974 Alpina dropped right out of the picture and Schnitzer were not represented in the new 4-valve era, which began officially on 1 January 1974. Schnitzers race results dropped right off as they began to feel the shortage of money in amongst the big boys in 1973 besides which, they were busy with work for customer engines at Feilassing and they were getting interested in formula car racing. They ran one of their smart silver CSLs for drivers including Vittorio Brambilla (whom the late Josef Schnitzer always respected and employed over a number of seasons), Henri Pescarolo and Bob Wollek.
Alpina were out because Bovensiepen has always treid to race what he can sell to customers; 4-valve-per-cylinder, six-cylinder racing engines were not on that list. "If we have to buy everything and then call it Alpina, there is no point for us to race. That is not a technical development that we can benefit from and sell", Burkard sadly stated. They did try their luck at the first Monza round of the European Championship, with Rikky von Opel / Helmut Koinigg. Running a 2-valve-per-cylinder head, the talented Austrian Koinigg (who was killed in a Surtees at Watkins Glen later that year) tried to make up the power deficit and damaged the car. It was a sad ending to Alpinas efforts after their pionering role, but they were to be back with a vengeance three years later, conquering the penultimate European Championship.
Just as the six-cylinder road engine was a close cousin to the four-cylinder, so the racing six-cylinder with 4 valves per combustion chamber was a very close relative of the four-cylinder, 4-valve engine first raced in Formula 2 in 1970 and then successfully developed into the dominating force in 1973 Formula 2. There was gear drive for the double overhead camshafts, the same hemispherical combustion chambers; titanium connecting rods (first born in the 1.6-litre Formula 2 days) and the same cast alloy Mahle pistons. Of course, the nitrided steel crankshaft was different, and it did have to be made in a more resilient steel than that used for the 2-valve sixes. Coded M49, this engine first raced and won at Salzburg in March 1974, when it developed around 435 bhp at between 8000 and 8800 rpm. As von Falkenhausen points out, theoretically the heads, with the same valve angles and the same dimensions as the Formula 2, should have been able to provide more than 9000 rpm as well, but the length of the six-cylinder crankshaft prevented this. The single slide fuel injection and leightweight pump from Kugelfischer were retained. The M49 engine remained the basis for all the factory efforts with the CSL, but Josef Schnitzer subsequently (in the winter of 1975/76) increased its effectiveness in a number of interesting ways when he arrived for his spell at the factory. Firts, he sorted out the exhaust system and had the engine mounted vertically in the car, instead of at production slant. This helped in several ways, for the inlet system could be straightened out, the head design modified so as to take advantage of the bigger exhaust pipes provided and the engine could become a 460 bhp unit; not far off Formula 1 standards, and very impressive for a production block unit. Then the head' water circulation and temperatures were improved for its higher power ratings in the new Group 5 with an external water line going out of the head between the spark plugs.
For the 1974 European season and the 1975 American season, when the CSL embarked on an IMSA racing programme, the pace of development slowed. The wings remained, but for 1974 a slinky dark blue basic body colour was adopted. The car proved shattering in speed, but rarely appeared in the 1974 ETC season ("not interesting for us anymore," I was told several times, but money and fuel crisis politics played a part), and the CSLs gave a remarkably good account of themselves when sent to America. In 1975, four CSLs went to America, one returning for use in the distinctive Stella-painted Le Mans project of 1976. For American racing they could get a little closer to 1000 kg, because both trim and some of the side-glass could be removed (even the dashboard could be taken out), and there was greater freedom over the wheel-arch extensions, so larger extensions were fitted. In fact, BMW, like Porsche and Ford, had been expecting the International Group 5 Championship of Makes regulations, based on a cars silhouette, to come into force for 1975, but when it did not, the marketing requirements of the States appealed a lot more than grinding the non-existent opposition into the dust in the European series. So, the old Group 2 24-valve cars were sold off in Europe (Alpina bought at least one), and BMW based themselves on the premises of stock car driver Bobby Allison at Hueytown, Alabama, in the heart of the South. Legend has it that Jochen Neerpasch could not afford to ignore the challenge when one American asked him if BMW stood for British Motor Works.
"The funny little European auto", as the Americans referred to the substantial CSL, was driven by a team that included Hans Stuck, Sam Posey, Brian Redman and Ronnie Peterson. Inevitably, Stucks European driving suffered a little as he struggled to keep up with the travel and changes in style involved in swopping from Formula 2 to IMSA.
The American experience was only partially abandoned in 1976. Peter Gregg, rather better known for his activities as a porsche privateer, represented the bavarian factory that season and the car continued to be quite competitive, though the sheer speed of the American V8 home-grown machinery, and the reliability plus the speed of the porsches, prevented Gregg enjoying the kind of success Braungart certainly felt the American deserved as a driver. "I remember, at Daytona in 76, it took Gregg only a few laps to settle down to Redmans time in the same car. Thats why we wanted him for 1976," the BMW executive told me. Gregg won two races for BMW in 1976 and returned to running his own Porsche in subsequent seasons. Altogether the CSL won seven IMSA races outright, Hans Stuck taking four such wins in 1975.
Meanwhile, 1976 saw some major changes on the European racing regulations scene. Group 2 changed over to a more restrictive formula, aimed at employing fixed wheel rim widths, small body wing extensions, comparatively unsophistacated suspension systems and wet-sump-lubricated engines, without the option of using 4-valve-per-cylinder heads unless they were mass-produced as original equipment. Only Fords Escort RS1800 and the Triumph Dolomite Sprint qualified under this heading. BMW were not directly interested in contesting this category, but Belgian preparation specialists Luigi Racing were. Using mainly Belgian drivers, the 370 bhp CSLs turned the clock back almost to the beginning of BMW development with their four-speed gearboxes and modest bodywork, though the wing system was still there.
In fact, Luigi had been a force to reckon with in 1975s Coupe LAvenir series, a Group 1½ series that had become necessary because of the poor support for the European Touring Car Championship after the Ford versus BMW war had fizzled out in 1974. Based at Comblaint-au-point, near Liège in southern Belgium, the team had developed out of the enthousiasm and practical skill of Luigi Cimarosti. A most unlikely team proprietor and garage owner, Cimarosty exhibited all the fire of his Italian ancestry yet endeared himself to everyone by working all the hours under the sun on his cars surrounded by a team of part-time timekeepers and team managers. The Luigi BMW team first achieved international recognition in 1974 when they won the modified Group 1 Spa-Francorchamps 24-hours, a feat they followed up the following year. By 1976 their activities had achieved some factory support (mainly for parts, especially lightweight body shells, the very last of which they fielded in 1977/78), and both Gunnar Nilsson and Hans Stuck were occasionally drafted into their cars to meet the very rare challenges offered by Group 2. It was a year spent waiting for the Leyland Jaguar to appear, which it belatedly did in September at Silverstone. Neerpasch was right to choose Group 5 for his main effort. While the factory-supported BMWs from Luigi simply mopped up the 1976 Group 2 title, Munich was not expecting much in the way of results in the new Group 5. Porsche had been developing their turbocharged 911 into the 935 racing car, and it was too formidable an opponent for anyone most of all the pessimistic Germans to predict any hope of modified saloon cars like the CSL having any success at all. In fact, they did very well, winning three rounds outright and turning the championship into a rather more interesting contest than we had any right to expect at the beginning of the year.
BMW took the decision to contest the series in December 1975, but none of the cars were built before February 1976. A brief test programme at Ricard established new leightweight and more aerodynamic bodywork. The plastic front wheel-arches and spoiler were similar to what had gone before, but the spoiler extended in real cow-catcher style; at the rear the wing extended out further with revised side-plates, and the wheel-arches were the biggest and most squared-off yet seen. They now accommodated Goodyear rubber BMW had flirted with the idea during their American programme the previous year and were of sixteen inch diameter, twelve inches wide at the front and fourteen at the back.
Somehow BMW managed to build four of these 1030 kg machines in time for the first round of the championship in March. On the tight Italian Mugello circuit they had one 1370 metre / 1500 yd straight where drivers reported a maximum rpm in fifth gear, corresponding to 161 mph (260 km?h). The four cars were for Alpina-Faltz, Schnitzer and a British-based Hermetite team runned by Carl "Tivvi" Shenton, plus a car retained by the works to push ahead with development. The idea was that the three customer cars would be reliable and pick up points while the works developed their turbocharged version of the 24-valve six-cylinder motor. That is exactly what happened.
The Group 5 cars proved remarkably consistent. Horsepower, between 470 and 480 bhp at 8700 rpm, was provided by the Munich factory, and the cars apparently all started off weighing within five kilogrammes of each other, a remarkable and rapid achievement.
Though the green Schnitzer CSL and the other two customer CSLs were spectacular in the hands of drivers like Brian Redman, Dieter Quester, John Fitzpatrick, Tom Walkinshaw, Harald Grohs, Sam Posey and Albrecht Krebs, everone was waiting for the turbo CSL to appear.
That the debut was as exciting as it was owed a great deal to the car, which the normally serious men of Munich saw as virtually a "motorized joke". Braungart described every fault lovingly as if describing some mischievous woman who entranced everyone; and thats virtually what the big white CSL, with its hughe stripes, did when Ronnie Peterson climbed behind the wheel for its three race outings in 1976.
Braungart recalls with astonishment now, "even the floor glowed red with the heat from the engine, it was colossal! We knew the car could not last for long in fact we were surprised when it lasted close to an hour at Dijon there was no way the transmission could take this engine. Did you know it could produce twice as much power as our Group 2 engines? But we did not turn the boost up this high For sure these engines will make 1000 horsepower one day " Braungart blinked thoughtfully behind his brown-tinted glasses as het detailed the chassis alterations they made to try and help the cars fifty-six per cent front, forty-four per cent weight distribution of its 1080 kg. Despite moving the water radiator to the rear and the use of 19-inch-diameter rear wheels, the irrepressible Peterson could set the tyres smoking in third gear as he headed for a fifth-gear maximum reported as 178 mph (284 km/h) on Silverstones Hangar straight.
The engine that made this possible actually measured out at 3.2 litres and had two KKK turbochargers set at 1.3 atmospheres. That allowed 750 bhp at 9000 rpm, compared with the best of 480 bhp that they had seen for the Group 5 unit of 3.5 litres with Kugelfischer injection. The installation was neat enough, but the extra weight was nearly all added in the nose; though the factory regarded this as appalling, Alpina had raced with far worse distribution figures, going up as high as 58.6 % / 41.4 % rear in 1974. The turbocharging work was very much Josef Schnitzers baby, and he left behind a legacy of practical experience that allowed a better installation for the M1 coupé to come. Compared with Porsche, the engine always had one advantage: a 4-valve head. These allowed BMW to use comparatively low boost for a high output.
That was the glorious swansong of the BMW motorsport-prepared CSLs. There were cars at the closing rounds of the Group 5 Championship in North America (which went to Porsche in the end), but at Silverstone and Dijon the late and great Ronnie Peterson proved he and the "Munich Monster" could run with porsche and create some excitement. Redman drove the CSL turbo at Le Mans, it held third overall, but retired with gearbox troubles.
In December 1975 production of the BMW Cs series of coupés ceased; the CSL finished its run a year earlier. Some 45,000 coupés of all types had been made and the car, in all its six-cylinder forms, had been briefly rallied by the factory during the Munich Olympic year. For many years, privateers enjoyed using the car successfully in competition, so extending its enormous tally of national and international victories.
The BMW competitions department had supported an obsolete model for a year in 1976, but it could do so no longer. Marketing pressure meant doing something with newer, current models in the range and the factory had to leave the car to the privateers there-after.
It says a great deal about the basic strength of the CS series that the privateers proceeded to do just that, and the car proved as successful as ever in European Group 2. In fact, no other marque or type won an ETC qualifying round between July 1974 when a Xakspeed Escort pulled off a surprise win in the Nurgburgring 6-hours and the CSLs ETC Championship appearance in October 1978. This was despite some highly professional opposition, including the Jaguar assault from late 1976 (one race only) throughout most of 1977, when Leyland ran the Broadspeed XJ 5.3 C.
The 1977 season saw Alpina produce their pride and joy; it
amounted to a brand new CSL, built up from one of the CSL shells supplied originally by
Motorsport GmbH for Group 2. In it, Alpina had expressed every talent they possessed, its
gleaming green paintwork and glittering mechanical components speaking louder than any
publicists voice of the enormous care and enthousiasm that had gone into building
perhaps the best-prepared touring car seen in Europe. The works cars were always highly
professional and eye-catching, but I agreed with Dieter Quester who, looking back on ten
years with various BMWs, simply said of the Gösser Bier-sponsored Alpina CSL, "It
was the best car I ever had. Fantastic handling, brakes, everything was good enough to
It was not just a pretty face though. On-board air-jacks, 16-inch-diameter centre-lock wheels, and a rear alternator driven from Alpina's unique driveshaft belt arrangement (similar in principle to the oil pump differential cooler) were employed. Everything Alpina had learned about BMW coupés was witin this remarkable racer. The engine began the year in wet sump form with some 325 bhp produced from 3.2 litres (standard 84 mm stroke and 89.8 mm bore), but when Leyland's political pressure made the CSI change the Group 2 regulations to allow dry sump lubrication late in the season, Alpina did eventually put the well-proven system on. It was chiefly this that allowed a yield of 340 bhp at the close of the year, with 8000 rpm the recommended maximum on the production crankshaft. The 1075 kg Alpina CSL had to use a four-speed Getrag gearbox under the new regulations, and this was equipped with the following ratios: 2.33:1, first; 1.47:1, second; 1.17:1, third; and direct 1.00:1, top.
It was the European Championship-winning car that year, and scored five victories. Luigi were also strong on the scene with two of their own CSLs, and an ex-Luigi CSL developed by Carlo Facetti and driven by himself and Martino Finotto; this one was often very fast and occasionally used Goodyear covers while the others stuck to Dunlop.
Alpina withdrew after winning the title and humiliating Jaguar, saying there was nobody to beat; they sold the car to Carlo Facetti and Martino Finotto. Once away from Germany and Buchloe, it simply lost its polish and preparation in 1978, and it was left to one of the persistent Luigi BMW CSLs, driven by wealthy Italian leather goods specialist Umberto Grano, to take the model's fifth European Championship in 1978. An almost meaningless title, such was the state of the art that year - though the addition of the Mercedes-Benz referred to at the beginning of the chapter did help a little. So far as technical developments were concerned, the great days were long gone. The car that brought winged science to touring car racing in Europe went on, a winner that would not lie down.