unleaded and ethanol
Race Director
Joined: Nov 1999
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From: Foxfield CO 1970 Convertible
The octane rating supposedly isn't related to the makeup of the fuel. Therefore 91 should be more prone to pinging than 93. In addition, ethanol reduces the amount of energy in gas by quite a bit, so I'd have to guess that this is another reason why the 93 will ping less... 
Race Director
Joined: Feb 2005
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I think ethanol has much less energy per unit volume than gasoline
so you have to burn more of it to generate the
same energy as a like amount of gasoline. The pinging could be timing....
Back in my dirt bike days,we ran alcohol...all I remember is it stunk and burned cleaner...
so you have to burn more of it to generate the
same energy as a like amount of gasoline. The pinging could be timing....
Back in my dirt bike days,we ran alcohol...all I remember is it stunk and burned cleaner...
Race Director
Joined: Nov 1999
Posts: 10,643
Likes: 8
From: Foxfield CO 1970 Convertible
Originally Posted by rihwoods
I think ethanol has much less energy per unit volume than gasoline
so you have to burn more of it to generate the
same energy as a like amount of gasoline. The pinging could be timing....
Back in my dirt bike days,we ran alcohol...all I remember is it stunk and burned cleaner...
so you have to burn more of it to generate the
same energy as a like amount of gasoline. The pinging could be timing....
Back in my dirt bike days,we ran alcohol...all I remember is it stunk and burned cleaner...
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Originally Posted by Z-man
That was probably methanol (methyl alcohol). Methanol packs quite a bang! Ethyl alcohol (ethanol) doesn't have much odor except in that godawful Jagermeister.
