Octane Rating of Canadian WWII vehicles

[Lynn Eades]

In saying all that, for Dan's benefit, The relatively low compression ratios of most war time engines was in the area of 5 or 6 to 1. This in most cases would have been pretty forgiving except that (as per Tony's post) most British vehicles had a very low power to weight ratio.(iets say a conservative approach to horse power)
Nowadays Dan, most European and Asian built cars are running about a 10 to1 compression ratio (often, on top of which goes a turbo)
It's all about volumetric efficiency which means stuffing as much as you possibly can, down the hole (the air fuel mix, that is)
I hope this all makes sense and I am sorry I've not yet found any info on the standard octane ratings of British fuel, during WWII.

[Alastair Thomas]

After the war was over, my Father mounted an expedition to visit Ain Dalla. This uninhabited oasis is NE of Farafra oasis to the East of the Great Sand Sea. It was a jumping off base for the LRDG and there were reputed to be stores dumps still there. And so it proved. There were boxes of flimseys and some jerry cans. Some of the flimseys still had petrol in them and my Father drove back to Cairo on it in his Jeep, some 370 miles. When he got the chance he sent a sample to the Shell offices and they analysed it for him. They pronounced it to be 53 octane and "should not be used in a motor vehicle"!
Having said that he also fitted a second fuel tank to his Jeep and would run on paraffin when the Police were not in evidence.
We still have his desert equipment including his bubble sextant and Cole sun compass. In a burst of enthusiasm I have just finished making a small batch of replica Bagnold sun compasses.
Alastair
F60S
Lynx I MkIII*

[Lynn Eades]

I love the (9.00?) x 16 sand tyre on the jeep. Does that equal low range starts?

53 octane. That is pretty low. Had all the petrol evaporated leaving the bunker oil?