I was very interested to read Mr. Burnell’s experiences with multi-grade oil and his conclusions regarding the price of oil generally. My experiences may serve to substantiate his own.
In January 1955 I purchased a new Ford Thames 5 cwt van, basically the same as the 100E Anglia. To this I gradually added seats and windows, a Handa overdrive, machined 0.060 in from the cylinder head and fitted larger choke and jets to the carburetter.
I also fitted a front anti-roll bar and rear radius arms of my own manufacture and succeeded in gaining awards in many local rallies. I fitted new pistons and Duaflex rings at 64,000 miles, when the oil consumption had fallen to 200 miles per pint, but did not have a complete engine overhaul until 84,000 miles, when the rings broke in one cylinder. Even then all the valves were usable again. For the majority of this mileage, I used a commercial grade oil, at 8s per gallon, and the fuel was a 50/50 mixture of regular and premium.
I was so pleased with the results that when I purchased the inevitable new Mini in June 1960, I decided to run on commercial oil after the 500 mile service. I fitted a Downton head with 9 to 1 cr, Sprite silencer, rich needle and no air filter element at 10,000 miles and my acceleration was then almost the same as a friends’ Anglia with an ohv conversion. I have just removed the cylinder head again at 30,000 miles and there is less than 0.001 in wear in any bore and all the rocker gear cleaned up as new when just washed in paraffin. Again all valves were usable.
I feel I must point out, however, that although I usually cruise in the 60’s, my daily journey is 15 miles each way which gets everything thoroughly warm and as I was trained as a mechanic, I do all my own servicing and change the oil and filter at the recommended intervals.
To my surprise, I find that many motorists do not even know that the large oil companies market new oil at 8s per gallon. It would be interesting to have the comments of an oil company on the following:
(a) Why commercial grade oil is unsuitable for use in the modern car ?
(b) What there is in the advertised oils to make them cost twice as much ?
GE Bath. Upper Swainswick.