Extended tuning test: The Spa 24 Hours in a Group 1 BMW CS !

If you read D.S.J.’s reports over a period of time, there comes a point when it seems you have to go and experience what he describes in his Continental travels, or be for ever damned for missing classic events that may never be held again. Strictly speaking my interests are confined to the addition of sparkle to what, for the main part, are ordinary family saloons. Occasionally there’s a golden opportunity to combine business and pleasure, and late in July just such a chance came my way: the BMW Concessionaires in Great Britain were backing a trip to Belgium for the Spa 24-hour saloon-car race, entering a pair of 2002 Tiis (under MLG and Cronks of Chipstead colours), plus a 3.0 CS coupé. Since I was quite well acquainted with BMW racing saloons (see the July issue) they asked me along for a co-drive with 2-litre sports-car specialist Peter Hanson, who’d just woken everyone up by breaking Chris Craft’s 3-litre lap record at Vila Real, using a 1.8 FVC-powered Chevron.

Before we left the legendary white cliffs of Dover, there were snags to overcome. The most pressing was the knowledge that only one car had been accepted on the main entry list, a Tii for Tony Lanfranchi and John Bloomfield. Our CS was fifth reserve in the over-2,000-c.c. division—all the classes as normal for the European Touring Car Championship, of which this was the sixth round. That means that the Group 1 machines had to take their chance against the more powerful, but often rather more delicate, Group 2 saloons, though there were separate monetary awards. The remaining Tii, for Roger Bell and Tony Dron, was also listed as a reserve, but in the 1,301-2,000-c.c. class.

However, our worries over travelling to Belgium, possibly for nothing, were little compared to the preparation schedule that Mathwall Engineering on Silver Mere Farm Estate, Byfleet Road, Cobham, Surrey, were facing. The Tii that Bell and Dron were to drive had been contacted vigorously in the rear passenger panel by a savage Ford Capri; Mathwall do operate a crash repair business as well as their engine and complete competition car side, so that headache and the changes needed for Spa were tackled over a period of a month or so. The other cars couldn’t be so easily catered for as they were occupied in British Group 1 events, the smaller one conducted by Bloomfield and the larger by Bell or BMW (GB) Competitions Manager, John Markey.

What changes are needed anyway if the cars are already competing in British Group 1 ? First, there are the obvious requirements of a 24-hour race in the forms of extra lighting to see with, and smaller identification lights for the timekeepers and pit crew; part of the latter “spotter’s aid” was the application of different Dayglow hues for the radiator grilles of the three machines. Next modification was the installation of simple quick-lift jacking extensions in steel, coupled up to equally effective tubular steel jacks, all with long arms for maximum leverage with minimum effort. The specification changes were quite radical too in that the standard seating and steering wheel have to be retained—the driver’s perch and wheel may be changed in the UK. The regulations intimated that a rather higher ride height was needed than that required in the UK.

In fact the CS was, like the other British BMWs, completely stripped to its component engine, transmission, braking and suspension part, the rebuild commencing after all the appropriate stress-bearing items had been thoroughly crack tested to aviation standards. Naturally all new disc pads (the CS uses ventilated units all round) and other routine service items, were changed for fresh parts. The straight-six-cylinder power unit had been through the blueprinting process. gaining the best part of 16 b.h.p., i.e., 198 b.h.p. at 6,000 r.p.m. in total, as compared to the 182 horsepower Mathwall discovered when testing the unit straight out of the CS, after it had completed only 600 road miles.

The power unit labour takes up the best part of a week, during which time the reciprocating components will be balanced, taking great care not to go below the stipulated individual weights of each item, the combustion chambers matched in volume, for a compression ratio of 9.0 to 1. Cylinder head port tolerances are generous on the homologation sheet from Munich, which allows Mathwall to improve the breathing somewhat.

The four-speed transmission was exactly as used in Britain, but the final drive for Spa was the optional 3.4 to 1, coupled into the recently (July 1st) homologated ZP limited-slip differential.

The end result of all these labours was lubricated by Castrol, sparked by Champion, further illuminated by Hella (a pair of “pin” beam spots for range, standard halogen lamps filling in the gaps), fuelled by Seca—which is a Continental associate of Burmah Castrol—retarded by Ferodo DS11 pads, whilst both wipers and the very efficient screen cleaner were supplied by Trico Folberth, who do take the trouble to send a pair of knowledgeable representatives for troubleshooting in an area notorious for heavy, sudden, rainfall and a fine collection of windscreen-smearing bugs.

Firestone supplied the tyres for the CS, which weighs over 27 cwt. in racing form with mandatory Group 1 roll-over bar. In fact Mathwall took the trouble to fit extra screen pillar crash bars and cockpit-operated fire extinguisher system, to complete the touring specification. The optional 6J alloy wheels carried 9.50-14 Firestones for dry use and the same tyre, but in 8.10 section with handcut channels, for damp track use.

Also included in the Mathwall schedules, apart from laying in all the spare parts they could get their hands on, were the construction of illuminated pit boards, using fluorescent light powered by 12-volt Ever Ready lightweight batteries. Incidentally, no less than 700 gallons of fuel were ordered for the three cars, but since one car did not run it was not all needed.

In the event, Mathwall partners Stuart Mathieson and Peter Wallace elected to work on the CS themselves, in company with (at different times, you’re only allowed three mechanics and a refueller) Andrew Mellentin, Stuart Bennett, and Peter Martinez; pit signals were shared between Tom Daws and Keith Polkey. Only Martinez and Polkey were drawn on from outside Mathwall’s own labour, both gentlemen working for Cronks of Chipstead, Surrey.

In all there were to be 27 people travelling in association with the BMW concessionaires, so Markey had plenty of managing on his plate. At Dover we were all loaded onto Townsend Thoreson’s Free Enterprise, without Markey, who was to chase over the next day with a missing carnet. “Our” flotilla consisted of a transit full of parts, a Transit with a Tii and parts, plus a poor Bedford van with a Tii on its back and the racing CS on a trailer! In addition there was, next day, Markey’s big BMW saloon with a caravan, the Motor journalists’ borrowed Bedford-based Motorhome, John Bloomfield’s roadgoing Tii—which was to be cannabilised ruthlessly—and the writer’s Capri hybrid. Although the Channel was rough, the boat arrived at Zeebrugge on time in the early hours of the misty morning and we set off behind Bloomfield, still rather perturbed at having suffered a broken mirror en voyage.

The Capri, fitted with stiff RS 2600 suspension, Avon crossplies and laden with four adults, provided a very bumpy ride over Belgian pave whilst the Tii in front barely moved its occupants at all at a steady 70-80 m.p.h. Once we were on the main Ostend-Brussels dual carriageway things got better, and it was not much more than three hours later that we drifted into Spa for breakfast.

By midday the BMW flotilla were also in town, so we crept out to the Mazda agency near La Source hairpin that was to serve as a base for the cars. In the mid-afternoon sun we had a little impromptu practice on the open roads, all aimed at seeing which way the bends went. In fact the Capri’s Avons coped well with the extraordinary demands placed on them, for even with such conditions, the really fast corners can be covered at 110 m.p.h. plus without strain. At this stage the thought of driving round the circuit without oncoming traffic seemed attractive. By the time the first 4-hour practice session started on the Thursday night at seven o’clock, prior to the weekend race, we had acquired a sheepskin cover for the standard plastic seat, rather necessary in the humid heat.

It was agreed that all three nominated drivers of the CS, John Markey was the third, would do four flying laps to qualify, prior to Hanson then setting out for the quick lap that could lift us off the reserve list and into the entry, a quirk of the Spa regulations that helps quicker late entries get into the race over the heads of those who put their paperwork in earlier but are not so rapid. At this stage it took Hanson 5 min. 5.8 sec. to cover the 8.7-mile circuit, whilst Markey and the writer recorded 5 min. 10 sec. apiece, so by the time we had all finished Hanson had to go out in the twilight, quickly knocking off over 2 sec. from his previous best in a couple of laps. At first it looked as though this was not good enough, for the blue and white Munich registered CS of previous Spa 24-hour winner “Pedro”/and Nicolas Koob was nearly 10 sec. under the 5 min. barrier, together with the Trans-Europ Opel Commodore GSE of Danial Wauters/Robert Coemans.

However the organisers seemed convinced that we had done enough to qualify as first reserves, just ahead of the unfortunate Bell/Dron machine, and in the event this was enough to get us onto the very back of the grid, the second practice session being rather wet. However, in that latter session the CS from Britain started to show its potential with a time very little slower than “Pedro”/Koob. Part of the improvement came from revitalised brakes—the system goes soggy straight after new pads are installed—and lots more from the suspension, which was quickly adapted to local conditions, i.e., we found out that it doesn’t have to stand on stilts for European Group 1 either! As in the event itself, the team of four Group 1 Autodelta Alfa Romeo 2000 GTVs proved very rapid and were far superior in straight-line speed to the British BMWs, a complete reversal of the situation in this country, though a quick look at the Alfa engines was enough to reveal that Italian homologation papers must list items not available in Britain!

I sat in the Press box overlooking the overcast, but dry, track with very mixed feelings, for it was obvious that it was going to rain by the time my stint was due to begin some three hours after the “off”. At the head of the grid two works Cologne Capris, Hans Joachim Stuck/Jochen Mass and Dieter Glemser/Alex Soler-Roig, sandwiched the shining silver Schnitzer BMW CS coupe of John Fitzpatrick/Hans Heyer, all these really quick (Stuck did 4 min. 4.0 sec., 207.862 k.p.h., without effort) machines at the front modified to advanced Group 2 specification. In horsepower the difference can be gauged on the figures given for our Group 1 CS and those quoted for the Kugelfiseher fuel-injected Group 2 Schitzer CS of close to 340 b.h.p. Cornering powers are totally different too, for the Group 2 machinery often employs wheel widths in excess of 10 inches, whilst production cars use the same or only slightly wider rims like those found in the showroom. The rest of a Group 2 car’s specification is naturally tailored along the lines of producing a proper racing car that just happens to look like a BMW coupé or Ford Capri, though many basic production engineering principles are unchanged.

So, while Hanson was passing over 30 cars during his session— which, like all to follow, was split into 1 1/2-hour lots to allow for refuelling after 20 laps (very roughly 180 miles)—I sat and lap-charted in traditional manner. In fact there was a goodish motor race going on for overall honours during those early hours as Fitzpatrick kept the big BMW in contention with the works Capris, shadowed by Toine Hezemans in the orange BMW Alpina CS. Heading this queue was the Capri of Gerry Birrell/Claude Bourgoignie which, after midnight had passed, was to be just one of the three works Capris that dominated the event as the BMWs suffered engine maladies. Fitzpatrick transfered from the CS he shared with Heyer after just such a problem and continued to drive at every conceivable opportunity in the sister car of Alain Peltier, replacing Christian Ethuin. Fitzpatrick’s stubborn and swift persistence paid off with a fourth place behind the Capris (who were led home by Stuck/Mass), despite some pit stops partially occupied with shouting.

Thus I scurried through the tunnel to rid myself of reporters’ equipment at 5.30 in the evening, persistent rain greeting me on my emergence from the tunnel. A quick change into pilotes‘ attire and I was crouched on the pit counter, awaiting the chance of maintaining Hanson’s fine record; the CS was 24th overall and second in class behind the Trans-Europ Opel, “Pedro”/Koob close behind.

It seemed as though there was no way to get into the car as it rolled to a halt, but frantic mechanics and a flushed Hanson soon cleared a gangway into the burning hot seat. Luckily both drivers were able to use the same seat position, so all I had to do was clip on the belts and wait for the bang on the roof that would signify a full fuel tank and “all systems go”. With a production exhaust system (a Continental requirement) the engine just couldn’t be heard, so with a mere 2,500 r.p.m. indicated I unwound the steering to thread a way through to the manned traffic lights that control circuit entry. Throughout the event I was to be lucky with this system, so it was only fractions later that I was pushing rather anxiously into the first bend. Within a few laps I had full confidence in the tyres that Firestone had supplied and, though we had chunking problem’s that needed alleviation with sidewall slots for a temporary cure to excessive sidewall heat, I was grateful throughout for the very progressive breakaway characteristics offered by such rubber. Honestly, if I had realised that this stint in the wet would involve corrective lock at well over 110 m.p.h. whilst blinded by spray from Group 2 cars I think I would have burrowed my way back to England in fright. Instinctively one reaches out for the gear-lever or the brakes to avoid unfamiliar obstacles like slower cars on the bit of road you want now, but the faithful pit boards, backed by Gordon Barritt’s unflagging 24-hour solid timing of the opposition and class stakes, plus “Tina’s” unfailing watch on our own times, soon sharply remind one never to let off until an accident seems inevitable. In these early laps I had found that the CS was gradually reeling in the Trans-Europ Opel, so I had quite an exciting first stint skirmish from which we emerged as class leaders by the time Hanson took over again. Now that I’ve seen how hard it is to pass an Opel at 125 plus m.p.h. into Stavelot, I can only gasp at the problems Rodriguez and Siffert must have solved whilst whirling their Porsche 917s around at an average exceeding 160 m.p.h.!.

As we drove into the night, and our overall situation kept improving until we were inside the top ten, the driving chores were a little more evenly spaced, though by the end Hanson had done the lion’s share of the driving hours, my tally totalling under 10 hours. I was relieved to find the track dry for the night stints and thoroughly enjoyed the sensation of the CS swishing remorselessly on behind flickering spotlamp beams. There was definitely no danger of boredom for either of us, for we still had that semi-works CS hounding, or in front of us, right to the sunny end at 3 o’clock on Sunday afternoon. In fact the Mathwall-supervised crew got so used to the tyre problem that they could fill the car with fuel, change two rear tyres, add 2 pints of oil and clean the screen in 48 sec., which may not scare the Americans amongst our readers, but certainly was enough to be competitive.

Daybreak, and the sight of the misty valley between Les Combes and the Masta Straight clearing itself of mist, was extremely welcome through streaky, grubby side windows. Although my overalls were clammy from a night’s exertions, and my hands sore from the sharpedged standard tiller, it was nice to see pit boards that recorded a gain over our rivals. In daylight the track crystalises in ones mind, and for the CS it worked out as three brake applications per lap, La Source hairpin in second and the quick 3rd gear twitch round Les Combes, plus a dab and third gear after the pits

The author needed confidence lifts from flat out top-gear work at Burnenville, Stavelot and the third left-hander in an ever-sharpening sequence of left-handers that lead down to the hairpin. Such driving produced a best lap in 4 min. 43 sec., while Hanson was caught at 4 min. 38 see. Thus for the majority of the course the tachometer indicated between 5,250 and 6,500 r.p.m. in 4th gear, a speed range of 115 to over 130 m.p.h.

Apart from the tyre drama, the CS had no problems whatsoever and went on through the bug-splattering heat of the day to finish seventh amongst 30 survivors, winner of the over-2,000-c.c. Group 1 class and second Group 1 car home overall—yes, one of those Autodelta Alfas got away to finish sixth overall! The British-based CS averaged 104.7 m.p.h. for 2,530 miles and gathered in an extremely worthwhile proportion of publicity for the marque in Britain, but any incipient big-headedness on my part was soon severely squashed again by British Club racing! — J. W.