On the road with a Type 57SC Bugatti
Cecil Clutton concludes the “Basic” era by trying one of the most intriguing of production cars.
When I complained, in a recent article, that I had never ridden in a Type 57S or Type 57SC Bugatti I little thought that I should have the good fortune to do so before the basic ration withdrew itself from circulation. However, shortly afterwards David Griffiths-Hughes wrote saying that he had recently finished converting his “S” to “SC,” and he had a tank full of petrol to use up before laying the car by at the end of June – and would I like a run in it? This would indeed be a grand finale to pleasure motoring and I naturally accepted his generous offer with all celerity and gratitude.
Gritliths-Hughes is a name which will be remembered in particular by Frazer-Nash owners, as David’s brother Evan was a spirited performer on that make in the middle thirties. Unfortunately, he has been killed at sea during the war, but his enthusiasm for motor-cars exists no less strongly in his brother, although his duty prevented him from doing any competition work before the war. His Bugatti is the coupé which previously belonged to Craig. It is not unlike Peter Hampton’s car, whose appearance is probably well known to readers, but it is better streamlined in front, the headlamps being enclosed in the fairings, while the back wheels have no spats. The body is a. 2-seater coupé with sloping one-piece windsereen and a sloping back, which contains the spare wheel and four suitcases. The wheels are chrome finished and the body has been repainted in two shades of grey, which is an undoubted improvement on the somewhat bizarre black and white of the ecurie Craig. The appearance is now extremely stirring, yet dignified.
Originally produced in 1935, the Type 57S normally had a compression ratio of 8.3 to 1 and was cursed by an extreme reluctance to start on a cold morning. It was also somewhat intractable, being fretful if run at less than 25-30 m.p.h. in top gear. Many owners, therefore, had their models converted to “SC,” and the blower not only put the b.h.p. up to about 220, but provoked quite exceptional flexibility and easy starting as well. Petrol consumption usually only fell by 1 m.p.g. and some 16 m.p.g. is not unusual on these cars. The compression ratio in “SC” form is 6.2 to 1.
220 b.h.p. is a quite staggering figure for a production 3.3-litre, exceeding even the 2.9-litre Alfa-Romeo, which is probably the Bugatti’s only serious rival to the title of the “World’s Fastest Production Car.” It is evolved at the permitted maximum of 5,500 r.p.m., equal to 66 2/3 b.h.p. per litre and a mean effective pressure of no less than 157 lb./sq. in. The engine is the well-known Bugatti double o.h.c. straight eight, 72 x 100 plot, with two valves and one plug per cylinder and plain bearings throughout. The traditional Bugatti multi-plate clutch was abandoned on this model and supplanted by a normal single plate and there is, as usual, no clutch stop. The gearbox is in unit with the engine, having constant mesh second and third, but no other aids for asses. The overall ratios on this particular car are 3.85, 4.98, 6.95 and 10.37 to 1, giving maxima, at 5,500 r.p.m., of 121, 88, 63 and 44 m.p.h.
The chassis is similar to that used by Bugattis for racing in 1936 and is exceptionally rigid. The semi-elliptic front springs pass through the tubular axle, which is articulated in the middle. This was supposed to give some degree of independence, but in one which was recently taken apart the joint had rusted solid. The Types 57S and 57SC had the very expensive de Ram shack absorbers all round and the front ones were made integral with the engine mounting in a most ingenious manner, the idea being to transmit the bumps to the engine rather than the chassis. There is probably not much doubt that a de Ram is the finest shock absorber ever made, but the trouble was that if it did get out of adjustment it practically had to go back to Mr. de Ram, at Paris, for attention. The latest Types 57 and 57C Bugattis wear large size, direct operating, piston type shock absorbers and the general consensus of opinion seems to be that they are cheaper, more reliable and practically, if not quite, as efficient as the de Rain. Rear suspension on the “SC” is the usual Bugatti reversed quarter-elliptic arrangement; the wheelbase is 9′ 9 1/2″; the ground clearance 4″, which is fatuous for ordinary road use.
Exceptional pains were taken to keep the front end of the chassis stiff, despite a slightly flexible engine mounting, and the cross member under the radiator is a most formidable business. Apparently of inverted “U” section, the underview discloses that the channel is filled by cross and longitudinal pieces, producing a very strong type of cellular reinforcement. The side members are of enormous depth, continuing almost straight to the rear spring mountings. The back axle then moves up and down through slots cut in the side members.
On the occasion of my run the addition of the supercharger had only just been completed and various minor adjustments had had to be left over. The most serious of these lay with the shock absorbers, of which the back ones had not been connected, while the front ones were only operating in strict moderation. As a minor annoyance which, however, precluded the taking of any genuine performance data, the complicated throttle gear had been hooked up slightly wrong, so that the last 15 degrees or so of travel on the butterfly was not available. Even so, however, some impressions of the performance of this magnificent motor-car may be of sufficient interest to retail to those readers of Motor Sport who have not had the good fortune to go in one of these somewhat rare vehicles.
In point of fact, at the last moment I nearly remained such a one myself, as only two days before the time appointed for my run in the Bugatti I had occasion to make a forced landing from a motor-bicycle at upwards of 80 m.p.h. However, I remained in active circulation and was able to clock in for my ride after all, although in a good deal of discomfort from my shoulders, upon which I had landed. A ‘bus ride on the same day had been quite a painful experience, but so comfortable was the Bugatti that I never felt any serious twinge during a fairly high speed run. Had the shock absorbers been fully operative, to have checked the excessive motion produced by large bumps, it would have been more comfortable still. Very few independent layouts could compare with the Bugatti, either for comfort or stability.
On the road the imperfect damping made itself felt in the shape of front axle patter under heavy braking and somewhat excessive pitching on the corrugated contours which so many roads are now assuming. This tended to provoke wheel spin on the straights and side-skipping on corners. That it was still possible to do most of one’s motoring between 70 and 90 m.p.h. is a powerful testimonial to the basic excellence of Bugatti suspension – but one did have to keep very much awake for possible developments after hitting any considerable bump at speed. It was distressing to think that, with the war-purposes-only motoring which was to become the rule within a very few days, one would not be exceeding a half of these speeds for the rest of the duration, even on the rare occasions when one did find oneself holding a steering wheel or a handlebar.
The driving position is fairly upright, in the excellent Continental tradition, and the feel of a Bugatti steering wheel is something quite unique in itself and fully in keeping with the rest of the steering mechanism. All Bugattis have a very wide lock, and on the Type 57SC three turns of the steering wheel serve to traverse it fully. This is a very comfortable ratio for touring. Probably as a result of having been in a garage for 18 months the steering on this particular car was noticeably heavier than is usual with Bugattis which, owing to the use of a positive trail layout, have always been able to combine exceptional lightness of operation with a high ratio.
The position of the gear lever, which is very steeply raked back from the unit-mounted gearbox, seems out of keeping on a Bugatti, and there can be no doubt that the human arm has the least possible control over a lever moving in this plane. In addition, the Type 57SC gearbox seems to have very little “feel,” while too accurately timed a change from top to third gear is apt to find the third gear dogs moving round at exactly the right speed but with the male members opposite to each other, so that the dogs will not mesh. This happened to me repeatedly. On any less flexible engine this might become rather a bore, but this engine is so unbelievably flexible that the gearbox can practically be ignored.
Fifteen m.p.h. is perfectly comfortable on top gear, while the most brutal jabs at the throttle pedal evoke no protests from the engine, even on “Pool” petrol and full advance. In fact, the normal procedure is to start in bottom or second gear, change immediately to third gear, run up to 3,000 r.p.m. (50 m.p.h.) and then into top gear. Once in top gear there is no temptation to change down again unless the road speed drops materially below 30 m.p.h. To show that this is no exaggeration we took some rough top gear acceleration figures, and even with the restricted throttle opening available it took only 6 or 7 secs. to advance from 30-50 m.p.h. and 11 or 12 sees. from 50-80 m.p.h. An overall figure from 30-80 m.p.h. was better than 18 secs. With this in mind, it seems that, while a 3.85 axle ratio might he appropriate on the unblown car, a ratio of more than 3.4 to 1 would be preferable on the “SC.” This would put the easy cruising speed up into the 90’s while still leaving all the top gear flexibility that anyone could demand. The higher indirects would also become more genuinely useful than the present assortment, the maxima then being 137, 100, 71 and 50 m.p.h.
The clutch is reasonably light in operation, but gives the impression that it would resent a getaway at much more than 1,200 r.p.m. The engine is commendably silent, considering the power it evolves, and with somewhat improved sound-deadening within the body itself it would be very good indeed. Even as it is, the noise inside this small coupé is by no means oppressive or such as would be tiring on a long run. The inflator is practically inaudible at all times.
With a suitable axle ratio and a body of this kind, the 220 b.h.p. is good enough to turn the speedometer up to the 130 m.p.h. mark, but on the occasion of my run the restricted throttle opening made itself felt above 90 m.p.h. and the highest speed I attained was 4,700 r.p.m., equivalent to 103 m.p.h., on a slight up grade.
The Type 57SC is a very remarkable motor-car indeed and one with which it is hard to find fault. But its outstanding characteristic is undoubtedly the power, flexibility and smoothness of the engine. To combine these features in the highest possible proportions it seems that a supercharged, inclined valve, straight eight unit has shown itself incomparably superior to all other forms of design, and the Type 57SC engine is surely the best of all.