"The Classic Twin-Cam Engine"

“The Classic Twin-Cam Engine” by Griffith Borgeson. 275 pp. 10″ x 7″ (Dalton Watson. 76 WardourStreet, London, WIV 4AN. £24.75

This is the long-awaited, very scholarly study by the painstaking American writer Griffith Borgeson, about the origins and development of the twin-cam cylinder head, in car, marine and aero-engine connotations. He sub-titles this verydetailed book “A Study of Man’s Pursuit of Power” and the title of his first chapter is “What Immortal Hand or Eye . . .”, which is taken from Blake’s “Tyger, Tyger burning bright, in the Forests of the night, What immortal hand or eye, Framed thy fearful symmetry?”. the last line of which concludes this learned book. Which, I reckon, just about sets the tone of it!

Some years ago Griffith Borgeson wrote a very enjoyable and clever article for the American Automobile Quarterly, in which he looked closely at the first multi-valve, twin-cam engines, unused for the 1912 Peugeot racing cars, deciding that Ernest Henry had designed them. and defending the Swiss engineer against later accusations that he had only had a small part in this important internal-combustion engine breakthrough, if any at all, or that hr had helped to steal the plans of this pioneer twin-cam engine from Marc Birkigt. It was a very fine piece of automotive detective work. for which Borgeson has since become famous, compiled after searching out and interviewing many of the persons behind the scenes, and at the time I followed it up in the pages of Motor Sport. Borgeson called those who teamed up under Henry to plan, design, and build the revolutionary Peugeot twin-cam racing engines “The Charlatans”.

His book is centred around this theme, and Part One. consisting of eight chapters, is called “The Charlatan Cycle”, its final chapter being titled “The Charlatan Mystery Resolved”, after the author has examined the factors and historical quirks leading up to the advent of the all-conquering Peugeot twM-cam multi-valve combustion-chamber configuration for racing. In this he looks in great detail at the work of many early engineers, at the beginning and culmination of those Peugeot twin-cam engines, with their off-shoots, and at the Ballot and Coatalen STD twin-cam power units that followed on. In the latter context he quotes from my article in Motor Sport about the Coatalen crib of the 1913 Peugeot.

Parts two and three of this erudite study look at, again in much detail and explanation, the pre-war European and American schools of twin-cam technology, in 25 separate chapters, covering the work of Delage. Alfa Romeo, Humber, Fiat. Aston-Martin, Salmson, Rolland-Pilain. Vauxhall, STD — the Bertarione era, Maserati, Amilcar, Alta, Bugatti. Lagorida Rapier, Triumph Dolomite, Austin 750, Mercedes. Benz and Mercedes-Benz, Frontenac, Richards and Junior Specials, Miller, Duesenberg, Packard, Stutz, Sparkes-Thorne and No.. As such engines were almost exclusively used for racing or in high-performance cars, and as Borgeson sorts out their reasons for coming into being, their idiosyncrasies, and so on, there is a wealth of interest in these chapters, which are amply illustrated with photographs and engineering drawings. On the matter of photographs, Borgeson has alnt dug out some rare pictures of Ernest Henry. the rest of his “charlatans”, and other personalities from the early years of his story.

Part IV of “The Classic Twin-Cam Engine” studies the post-war period, being called “The Modern Twin-Cam Engine — A Graphic Overview”, and the book concludes with bibliography, tabulated data about the leading twin-cam engines dealt with in the text, and an Index. It is deep stuff, unlikely to appeal to those who will read, for instance, Rivers-Fletcher’s rather superficial book about his MGs! But to those who crave as much motor-racing history as they can lay their hands on, to engineers, students of automobile design, and the like, it will be essential reading.

I have very few quarrels, indeed, only mild comment, on Borgeson’s findings and persuasions. In looking at side-valve and push-rod engines of almost all configurations (and incidentally, agreeing with John Bolster that the d.o.h.c. head was developed by simply inverting a T-head engine), I am not sure that Griffith Borgeson has made enough of the coolant problems involved with the latter, at least in his opening observations on these engines, and I think he might have quoted the weight of push-rods and rockers as affecting valve-bounce, as well as this weight being costly in mechanical loss terms, instead of putting the flexing of push-rods and rockers as the main cause of unwanted valve-float. The supercharged Stutz Bearcat engine does not appear to be mentioned, with its lever-operated forced-induction, or was this only available on the British market? Although almost every important twin-cam engine is included in the book, there is no revelation as to the one that was used in that Brooklands Buick of the 1920s, or whether the 3-litre Sunbeam was looked at by Heynes before he embarked on the immortal XK 120 Jaguar engine, nor, I think, does the author refer to those special Type 172 d.o.h.c. Peugeots that appeared in 1925, although the d.o.h.c. four-valve Peugeot motorcycle engine is mentioned. Other d.o.h.c. car engines which Borgeson has either overlooked or does not regard as important include the rare sports versions of the 12/40 Darracq, the Maudslay with its eccentric-driven oh. camshafts, the Singer-HRG head. the Newton-Ceirano and a few others, unless these have eluded me. This is a book essentially about the twin-cam engine, so it is permissible for push-rod actuation of inclined o.h.-valves to be largely ignored, apart from a diagram, but perhaps the 328 BMW, 14/45 Rover. Humber, Chrysler, and other systems of getting a hemi head without a second camshaft could have been enlarged upon. Bergeson’s source-material seems a little shaky, when he says that one of the F. T. Burgess-designed d.o.h.c. Humbert made fastest lap in the 1914 TT, according to S. C. H. Davis — by my records this honour went to Riecken’s Minerva, at 59.3 m.p.h. By the way, may be Anthony Blight, who thinks one camshaft is too many, should be called upon to reply to Borgeson’s question, in his Chapter 2 heading “Why Use Two When One Will Do?” . . . ! The Riley, Meadows and Lea-Francis highcamshaft/push-rod o.h. valve-gear may have been ignored, as outside the book’s context, but what of the 2-litre Lagonda’s two “underhead” camshafts?

The post-war chapter is rather a mix-up of racing with sports car or production-car d.o.h.c. engines, and of course Borgeson has, as we all have, to USE manufacturers’ b.h.p. figures, on which, in this case, so many vital conclusions and comparisons are based. But the case is well argued, in very readable style (even if in this very technical discourse the GP Mercedes are referred to by the journalistic term “Silver Arrows”), so here is certainly a book to buy for Christmas — and one which will occupy the reader over much more than a short holiday! — W.B.