壓縮比
The Standard Vanguard used the same 2,088 cc "85 mm" engine that had been developed for the tractor. Compression ratio remained the same at 6:1 but the valve and ignition timing were changed to suit road driving conditions and a more predictable quality of petrol. The governor was removed and the power output rose to 68 bhp. The Phase III version of the Vanguard, introduced in 1955, had a compression ratio of 7.5:1 but the power output remained at .