Octane ratings can be very easily calculated by simple averaging. For example, the tank of an Audi A4 1.8TQ is 15.6 gallons. Filling it with 14.6 gallons of 92 octane and 1 gallon of toluene (114 octane) will yield a fuel mix of:

(14.6 * 92) + (1 * 114) / 15.6 = 93.4


now what i am confused on is the 15.6 this seems to be the full tank volume. but if tank volume is changed to 40 gallons. octane would be

(14.6 * 92) + (1 * 114) / 40 = 36.43

what the hells going on here i am utterly and totally confused..

 

In the second formula, you haven't factored in the correct gas tank size on the left side of the equation.

Sonny

 

Assuming a full tank you need to chang the first number in the formula:

(39 * 92) + (1 * 114) / 40

EDit: ya what sonny said...


[Modified by mos, 10:27 PM 3/20/2003]

 

no read the example..

14.6 is the amount of fuel that is actually put in the car..

 

if you put in 15.6, divide by 15.6. if you put in 5 gallons of 91 and 1 of 114 it would be ((5*91)+(1*114))/6 = blah.

 

/6?

dont u mean /5?

 

sorry call me a moron!

i get it now.
14.6 gallons gas + 1 gallons toulene = 15.6 liters.

i get it now!!
DUH

 

i meant a total of 6 gallons, sorry.

 

toluene can be used as race gas? wtf... ? i can get that in my chem lab...haha wonder if its pure methyl benzene or with additives.

krazy

 

umm 14.6 gallons + 1 gallons = about 60 liters actually...
In your original post you are measuring in the empty air space as zero octane. Hrrm, anybody know what the octane rating of air is?

You might be able to get toulene in your chem lab, but the cost is probably higher than just going out and buying some race gas for four dollars a gallon.

 

14.6 gallons gas, 1 gallon toulene = 15.6

15.6 is the total tank.. thats what i didnt get i know now.. so

like 13.6 liters gas 2 gallons toulene = 15.6 .. 103 octane...

 

Wrong again. There are about 4 liters in 1 gallon. Ok I'll stop now.