Simanaitis Says

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YESTERDAY, WE took a brief look at future shock in motor sports’ past decade. Today, we examine earlier enthusiasts’ future shock with the help of Pomeroy’s The Grand Prix Car, Volumes One and Two. We learn some Latin too.

Pom’s Analyses. By contrast to yesterday’s more recent examples, consider Pom’s analyses of Grand Prix cars from the beginning to World War II’s cessation of competition. “Between 1906 and 1914,” he wrote, “and especially between 1912 and 1914, the outward form of the Grand Prix car underwent a radical revision…. From this point onwards the changes in design, shape, and frontal area have been more subtle and these drawings have been especially prepared to a uniform scale so that successive stages can be readily followed.”

Two-Seaters. Until 1925, international regulations required a driver and on-board mechanic, typically with the latter offset longitudinally. By 1925, the two were seated lower, reducing frontal area and thus aerodynamic drag.

The 1920-1921 3-liter Ballot and 1925 2-liter Delage. This and the following illustrations from The Grand Prix Car, Volume Two.

Pom estimated the 1920-1921 Ballot’s frontal area at 12 sq. ft.; the 1925 Delage’s, 8 percent less at 11 sq. ft. Also, the Delage featured a cowl over its front suspension, thus reducing turbulence and drag.

Offset Single-Seaters. “From 1925 onwards,” Pom wrote, “only the driver had to be accommodated in the racing car and this led to the construction of offset single-seater chassis and body….”

The 1925 2-liter Delage and the 1926–1927 1.5-liter Delage.

“In the Delage design,” Pom observed, “the crown wheel and pinion was offset approximately 4 in., to the lefthand side of the car, and this made it possible to mount the single seat to the right as to avoid the need for giving clearance for a propeller shaft beneath it. The result, in the outline shown shaded in this drawing, was a remarkably low overall height with a frontal area of only 9 1/2 sq. ft.”

Central Driving Positions. Pom cited “The success of the 1932 P.3 Alfa Romeo Monoposto popularised a central driving position with a seat high mounted above the propeller shaft. This gave a greater frontal area than the extremely low offset single-seaters of the 1926–1927 period, but offered the driver an excellent and symmetrical view of the road.”

“This theme,” Pom wrote, “was continued by Mercedes-Benz with their 1934–1935 Type W.25 A and B cars, but as these models had independent suspension to the rear wheels, no provision had to be made for the rise and fall of the propeller shaft…. An effort was made to reduce wind resistance by providing a deep fairing behind the driver’s head, but the nose of the car remained blunt with a vertical rectangular air opening to the cowl.”

The 1934 4-liter Mercedes-Benz and the 1939 3-liter Mercedes-Benz.

“By successive development through the 1936–8 period,” Pom continued, “the V.12 cars in 1939 had a long tapering nose with a low set oval air intake.”

Bodywork enclosed almost all the chassis bits.

The 1939 Mercedes-Benz; a detailed look from The Grand Prix Car, Volume One.

Pom also noted an aspect that remains topical today: “… one can see at a glance the immensely greater proportion of the frontal area represented by wheels and tyres, which are obviously extremely bad shapes from the viewpoint of wind resistance.”

An Example of Pom’s Erudition. In the Foreward to The Grand Prix Car, Volume Two, Pom wrote of 1939, “Since then, a further six years have gone by, and a man who saw the 1939 cars in action, just before he came of age, is now nearer forty than thirty. It is all too easy to echo the cry ‘Eheu! fugaces Postume, Postume,/Labuntur Anni…’ and the rest of these melancholy lines.”

Just as Pom thought we shouldn’t be challenged by technicalities of crown wheels and pinions, he assumed a bit of untranslated Latin was fine too.

“Alas! Really really fleeting years slip….” ds

© Dennis Simanaitis,, 2019

3 comments on “POM ON RACECAR BODYWORK, 1920–1939 PART 2

  1. Mark W
    July 5, 2019

    Thanks for the translation, I was going have to look that up!

    • simanaitissays
      July 5, 2019

      Thank Google Translate, although I must admit I’m tempted to look up the original.

  2. kzhw
    July 5, 2019

    Talk about my “small Latin and less Greek”… Well, aerodynamics are one thing, but the political dynamics of today’s F1 – three hours to declare Red Bull the winner in Austria following the Ferrari fiasco are more turbulent and time consuming. As always quirky, erudite and enjoyable. -Z

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