Opinion: The DFV is the greatest racing engine of all time

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mclaren cosworth DFV engine

The Ford Cosworth V8 won more than 150 grands prix and was instrumental in revolutionising F1 car design.

The greatest racing engine of all time. That’s a bold claim maybe, but over the course of 16 years from its debut on 4 June 1967, the Ford Cosworth DFV won more than 150 grands prix and was instrumental in revolutionising the way Formula 1 cars were designed.

Astonishingly, the DFV was also the first racing engine that its creator, Keith Duckworth, had designed entirely from a clean sheet.

The statistics behind the naturally aspirated 2992cc 90deg V8 make impressive reading even today. DFV stands for double four valve, because the flat-plane crank effectively gives the same configuration and firing order of two four-cylinder 16-valve engines.

spain 74 fittipaldi 0

The block was cast aluminium with ‘drop-in’ cast-iron liners and the two cylinder banks were staggered to avoid the need for forked connecting rods. To keep the engine gas tight, with its 11:1 compression ratio, the cylinder heads were sealed to the block using Cooper mechanical joints – effectively gas-filled steel O-rings.

The four camshafts were gear-driven from the front of the engine, it had dry-sump lubrication and three oil pumps featured, two to scavenge oil from the sump and one to pressurise the oil to a high 85psi.

There were two water pumps and, mounted between the vee, a Lucas mechanical fuel-injection system with eight slide-throttle bodies topped by eight large-intake trumpets. The ignition system was originally a Lucas Opus (oscillating pick-up system) but was soon scrapped in favour of a capacitive discharge system manufactured by German firm Walter Scherag.

The first version produced 302kW at 9000rpm and 332Nm at 8500rpm, with the rev limit set at 9500rpm, but there was more to the DFV than its immense performance and spine-tingling soundtrack.

When Duckworth was commissioned to design the engine in 1966, he made some bold decisions. One of those, after discussions with Colin Chapman at Lotus, was to design the engine as a stressed member forming part of the chassis and supporting the rear transaxle gearbox. It would be constructed as a plug-and-play unit to avoid failures from ancillaries fitted by other parties.

The first car to run with a DFV and designed around it was the 1967 Lotus 49, designed by Maurice Phillippe. The 49 was based on a fully stressed monocoque aluminium tub, the sleek lines of which ended abruptly in a firewall immediately behind the driver. The DFV was bolted to the firewall and the engine and transmission were bolted directly to it, using just two plates to the cam covers and two bolts on the sump.

Jesse Crosse

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