10 hour service on 2550

[JTKub]

If the gas station pump has one hose, it's a mix pump where mid grades are a mix of hi & low. I too always thought high octane fuel had slower burning properties. This was until one of the ex refinery tech guys I work with slapped me. Octane rating is nothing more than a fuel's resistance to detonation/knock. Octane # has nothing to do with a fuel's burn rate, etc. That said, unless you are waaaaay up above sea level, you are wasting cash buying more octane than you need.

Joel

 

[Bob_Bainbridge]

If the gas station pump has one hose, it's a mix pump where mid grades are a mix of hi & low. I too always thought high octane fuel had slower burning properties. This was until one of the ex refinery tech guys I work with slapped me. Octane rating is nothing more than a fuel's resistance to detonation/knock. Octane # has nothing to do with a fuel's burn rate, etc. That said, unless you are waaaaay up above sea level, you are wasting cash buying more octane than you need.

Joel

You are correct that octane is a measure of the fuel's resustance to detonation but as the following URL explains, leaded racing fuel will burn slower than unleaded fuel. Lead used to be used to raise the octane number.

Wrenching with Rob--Chemical Soup: The Meaning of Gas.

Bob B.