What is the most expensive gas per gallon?

[Torog]

What is the purpose of getting high octane gas? I've always wondered does it improve performance of regular cars? What exactly does it do?

Howdy dazen,

High octane fuel is used for high compression engines..like the ones that can be found in sports cars and race cars,also aircraft motors. Chrysler used to make alot of high compression engines..the Hemi,is a high compression motor,for instance. It can improve somewhat,the performance of a regular compression motor,but you'd need to change the spark plugs out with some 'hotter' plugs..to git the advantage. There's also a danger,that the motor ain't esigned to handle the hotter combustion temps that high octane fuel generates and damge could result..like scorching of the cylinder and valves,as well as the pistons. Back in the '70's,we used to put 93 octane fuel in our hotrods,along with a gallon or 2,of 'jet' fuel,which ran about 104 to 118..I think. I hope I helped to explain better.

Have a good one !