Thursday Trivia

Welcome to Thursday Trivia where we offer up a historical automotive trivia question and you try and solve it before seeing the answer after the jump. It’s like a history test, with cars! 
This week’s question: What was the world’s first DOHC four-valve per cylinder racing engine?
If you think you know the answer, make the jump and see if you’re right.
If you’ve been around as long as I have, you’ll probably remember when a DOHC four-valve per cylinder engine was a big deal. Hell, there were special models devoted to the engine, cars like Toyota’s FX-16 Corolla and VW’s 16V Scirocco. That may seem quaint by today’s standards when this once exotic technology is the norm rather than the exception, and as you might expect, this method of increasing engine efficiency through enhanced breathing was at first tested and accepted in the racing community.
In racing as in many aspects of life, regulation drives innovation. Limit one method of going faster and automotive engineers will devise another. In the case of the multi-valve head the regulations were enacted by the Grand Prix de l’ACF, which after seeing domination in the series by cars of enormous displacement set a standard of 4-cylinders not exceeding 7.6 litres in total displacement.

Robert Peugeot, the industrialist, saw little value in racing to sell his cars, but acquiesced to the pleas of his drivers—Jules Goux and Georges Boillot—to shift focus to Grand Prix racing and to hire driver Paolo “Paul” Zuccarelli away from Hispano Suiza to fill out the team. The three racers worked with a Peugeot draftsman, Erest Henry, to design a competitive Grand Prix car, and they did so with a budget of just four-thousand Francs.  The results of those actions led to a first in racing history, that also served as the nascent point of what’s today an almost ubiquitous engine technology in both racers and road cars.
From Hot Rod Engine Tech:

In 1912 three racing drivers and a forward thinking draftsman (early hot rodders) convinced Robert Peugeot to adopt a radical new approach to Grand Prix racing engine design. Conspiring with draftsman Ernest Henry they conceived the world’s first dual overhead cam, four valve per cylinder racing engine, the Peugeot L76.
Grasping the core concept of optimizing engine airflow early on, they believed that feeding the engine with twin cams and more valves could realize significant power gains from a lighter and more compact engine. Peugeot was already a successful automobile manufacturer with an impressive staff of technical engineers who remained unimpressed (read that jealous) by their theories; quickly dubbing them “Les Charlatans.” Along with Henry, the group included noted European Grand Prix drivers Georges Boillot, Jules Goux and Paolo Zuccarelli.

The car would prove more than competitive on the Grand Prix circuit as well as on others. In 1913 Goux would drive an L76 to victory at Indianapolis, up against cars with more than twice the little Peugeot’s displacement. So impressive were the Peugeots in fact, that they started a rush to duplicate their designs and hence their success. Today we have cars with more than four-valves per cylinder in the search of the ultimate breathing efficiency, but no matter how many there are, they can all trace their lineage back to the little Peugeot that could.
Image: Grand Prix History

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3 responses to “Thursday Trivia”

  1. Batshitbox Avatar

    Realizing they were on to a good thing, Peugeot quickly made a DOHC 4-valve motorcycle, the 500 M, also designed by Ernest Henry, and a world record holder in the flying kilometer, at 122 kph. WW1 killed the development, and post war versions were 2-valve. DOHC 4-valve motorcycles would not see mass production until the Yamaha TX500 in 1973!

  2. Tomsk Avatar

    The L76 was also the inspiration for the smaller Miller four-cylinder, which in turn beget the Offenhauser that, in turbo form, powered Indy cars into the early 1980s.–uFkOI3xS–/c_scale,f_auto,fl_progressive,q_80,w_800/noiafetaitnnfrlo9cjp.jpg

  3. outback_ute Avatar

    Had the car but not the year (I guessed earlier).
    Looking for some info on cross-pollination of the DOHC idea, I came across the 1910 Sunbeam race car “Nautilus” which had a 4.2L 4-cyl engine with 16 overhead valves operated by two camshafts, one on
    either side of the crank case. In 1911 they changed to a SOHC.

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