By the way you can look up these terms by Clicking on the (Glossary) which is at the top of the Page on the left hand side of the line that also says (New/ Recent Post) and it will let you look up all the neat little terms used on the Post here.
HTH;
Terry
Thank you for that . Have now found the glossary but it does not show FE or EV. Understanding your jargon is very important for a newcomer. The interest which you all share has opened my eyes to a new aspect of motoring.