The article by Peter Hull in the current issue of the Bulletin of the VSCC, on the Ford-powered Montier Specials, in which he refers to their appearance in the 1927 Coupe de la Commission Sportive at Montlhery, reminded me of the technical ingenuity used to win this unusual event. It was run under a restrictive fuel allowance, like that which applies to current Formula One racing.
Competitors were limited to 97 lb of petrol and oil for a 248 1/2 mile race, and this had to include any lubricant used in the transmission system. I am not sure how much a gallon of petrol or oil weighs, but the quantity of both which the organisers allocated to each car would have been rather under eleven gallons. Now the Peugeot Company was anxious to win this race, perhaps because it was run the day before the French GP, which brought crowds of some 100,000 from Paris and elsewhere to watch it.
Indeed, so keen was Peugeot to win the Commission Sportive event that it built special cars for it. Standard 80×124 mm, 2.6-litre engines, but with a compression ratio of 7.9:1, were installed in special chassis with thin girder-like side-members through which passed the front and back axles, the wheelbase being 8 ft 1 in.
Streamlining was carefully attended to, by enveloping the chassis and running gear within the body, which was of thin sheet aluminium, sitting the driver down low on the nearside of this single-seater body, and off-setting gearbox and prop-shaft to the right. Front brakes were dispensed with. The unladen weight was 11 cwt 61 lb, and power output was about 72 bhp. Peugeot had the benefit of Andre Boillot as their leading driver, though he was badly affected by acute facial neuralgia during the race.
However, there was a snag. Peugeot used Knight-type double-sleeve-valve engines, known to drink oil heavily. The solution was to use only 1.1 gallons of oil in the sump, cooling this in part of the water radiator, oil therefrom being pumped to the engine. Peugeot engineers calculated that this would be sufficient to slake the thirst of even a double-sleeve-valve engine turning at racing speeds, and expected each engine to finish the race with half a gallon remaining. To have enough petrol for the race they decided not to use any of their allowance on oil for the gearbox.
Instead, special gearboxes were fitted, in which top gear was selected after the cars’ had started and the layshaft immobilised at the same time. In this way only two ball-races would be involved and it was thought they could last the distance sans lubricant . . .
It worked out as Peugeot had planned. Andre Boillot, brother of the late, great Georges, led for most of the race, after some difficulty in starting, due to the weak mixture demanded by the fuel restriction ruling. He lapped low down the banking, at just over 60mph, to conserve fuel.
The four-hour race must have been dull for both onlookers and drivers until the last lap, when Goutte’s Salmson and Dore’s Corre-La-Licorne closed up on the leading Peugeot, which was obliged to use much more of the banking and go up to 100mph to shake them off.
Goutte’s petrol tank then shifted, cutting off the fuel, so it was Dore who crossed the line 0.2 secs behind Boillot, who had averaged 63.89 mph. Goux’s supercharged 1½-litre Bugatti was third, cocking-a-snoot at the fuel-restriction rule; maybe Ettore was anxious to convince his public that forced induction need not mean high fuel consumption?
Perhaps Peugeot was lucky, because the second car, driven by Louis Rigal, took 8 min 20 sec to get away from the start (the weakened mixture not suiting the special gearbox?), and eventually retired. Incidentally, this odd race saw some true “starting-money” specials, or perhaps I should call them “entry-fee specials”: the team of three Lombards were deemed insufficiently prepared for the event, but ran for a lap in order to recover their entry fees, as the regulations allowed.
It is a reflection, on the progress made in sleeve-valve engine development that, whereas the Peugeot engineers were able to run their special cars in this 1927 race on only just over a gallon of engine oil (and expecting that just over half-a-gallon would suffice, giving a consumption of around 450 mpg), it has been reported that before the second day’s racing in the 1914 Isle of Man 600-mile TT ten gallons of oil were poured into Porporato’s Minerva, which had a Knight-type double-sleeve-valve engine only 708cc larger than that of the 1927 Peugeot engine. It averaged 12.52 mph less than Boillot, in coming home fifth.
One assumes that the used oil had been drained from the Belgian car’s engine before the start of the second day of the TT, otherwise it would have even more lubricant in its system than the fresh ten gallons put in before starting-up again.
Anyway, for Peugeot technical ingenuity paid off, and I hope it helped to sell the contemporary production sleeve-valve cars. The racing Peugeot had averaged better than 22mpg and it had, like today’s Formula One cars, a gauge telling the driver exactly how much fuel remained in the tank at any point. the race. WB