On a related subject. Tyre pressure gauges.
Not sure what is correct the garage forecourt machines or my rather expensive gauge. Why
Well having driven to 5 garages & checked the pressures all were virtually the same. I sent 2 different type of pressure gauges back as they under reading (compared to garages) Decided to buy the expensive one which also under reads by about 2 lbs.
2 lbs seems to make quite a difference on my 4/4 which makes the above kind of interesting in that, am I running 20f 22r or 22f 24r ? Note my morgan service centre gauge matches the forecourt machines.