Delage 15-S-8 Grand Prix
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Car producer : |
Delage |
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Model: |
15-S-8 Grand Prix |
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Year: |
1926-1927 |
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Type: |
Roadster |
In 1914, Delage unveiled their ground-breaking Type S Grand Prix model—boasting twin-overhead camshafts, four valves per cylinder, desmodromic valve operation, and four-wheel brakes—while later that year, Rene Thomas gave the company their first significant overseas win with victory in the Indianapolis 500. Featuring a remarkably intricate 2-liter, four-cam V-12 engine designed by Delage’s cousin Charles Planchon, the new car debuted in the 1923 French Grand Prix. It was not until its appearance in supercharged form in 1925, however, that it was truly competitive, winning as it did at Montlhéry and at San Sebastian.
For 1926, Grand Prix regulations stipulated a minimum car weight of 600 kilograms and a maximum capacity of 1,500 cubic centimeters, either supercharged or un-supercharged. To this end, Planchon’s replacement Albert Lory designed the remarkable 15-S-8, almost a century after its introduction, as it was when it made its race debut at that year’s European Grand Prix at San Sebastian. Featuring a broadly similar chassis, braking system and transmission to the 2 LCV, the 15-S-8 was powered by a new 1.5-liter blown straight-eight engine which, certainly in pure engineering terms, surpassed any previously seen. Featuring a nickel-chromium crankshaft located in no less than nine roller bearings, gear-driven twin-cam valve operation, and a two-stage Roots-type supercharger, the new engine produced some 170 horsepower at 8,000 rpm, the latter figure being almost unheard of at the time.
A small series of 15-S-8s were constructed for the 1926 season, with the car immediately competitive if somewhat ergonomically compromised due to its driver’s side-mounted exhaust. Excessive heat and poor ventilation forced Bourlier and Senechal to share driving duties to finish second at San Sebastien, with Senechal and Wagner doing the same en route to victory at the RAC Grand Prix at Brooklands. For 1927, four Works examples were prepared for Grand Prix competition utilizing many components from the 1926 cars in substantially re-worked form. Modifications included relocating the exhaust and shifting the engine four inches to the left to lower the driver’s seating position.
