Fuel injection plugs

[Greg Hermann]

>Greg:
>    I must point out that this statement is erroneous:
>
>> Gasoline also has more energy per unit
>>>volume than diesel fuel, right?
>>
>>They are really quite close on a volume basis! within 2% or so, with
>>gasoline a bit ahead.
>
>Actually on a weight basis they are quite close..... by volumn diesel
>has considerably more energy.  There is actually a fairly close
>correlation between fuel energy and fuel weight.         H.W.
>
>

I think the truth of the answer depends upon the individual blends--the
numbers are pretty close.

According to Obert--

Lower heat of combustion: iso-octane: 19065 Btu/lb.; hexadecane (cetane):
18,898 BTU/ lb.

Specific gravity: iso-octane: .692; cetane: .773

I think I may have mis read the s.g. for the cetane before--this looks like
the cetane would come out a bit ahead on a heat of combustion per gallon
basis.

Regards, Greg