where did your mech go to school, crackerjack college where all you have to do is open the box and have the brains to shake prize from the box?

 

it was actually the salesman who told me not to use premium. doing a search online, it seems the altitude does affect octane by reducing the air pressure and compression. but i guess i'll use premium. better safe than sorry.

 

Yes altitude does have some affect but if the gas stations around you have 93, use it.

 

a quick octane lesson for those interested.... octane is the measurement of how fast a gas burns....and it sorta works backwards of what you may think....any given volume of LOW octane fuel burns faster than a high one. Imagine for a second if the combustion /explosion going on in your cylinder volume were to happen BEFORE the piston was in position to accept (or make efficient use of ) it would hit or "knock" the top of the piston at the wrong time......thus the pinging, knocking, associated with low octane fuel......in an engine like our Rovers have , that wasn't designed for low octane fuel in the first place.
That same volume of high octane fuel makes the combustion event (pressure on the piston)occur at the right time and quite possibly last longer in the cylinder......better performance and economy.

 

Anything to make a sale....


If our engines had a EGR you could use regular grade gas at the higher altitudes, but they dont.
So you will still have the excessive heat build up.