CORSA IFP wrote:
So if you think you're getting all 91 you're wrong. If you fill up from dead empty about 1/4 to 1/3 of your tank is going to be whatever was in the hose before.
ritchj wrote:
When the state inspectors certify the pumps, they pump out 5 gallons of fuel and measure it to make sure that the pump dispenses exactly 5 gallons.
They also check to see how much is left in the hose, to make sure people are not getting ripped off, and also to test the capture system that the government mandates for all modern pumps: vapors and fuel are captured and returned to the holding tank so they do not pollute the environment.
The amount left in the hose after pumping 5 gallons averages about 1/4 cup. So even if you only put in 1 gallon, only 1/64th of your fuel is not the right octane, not enough to make a difference.....
Standard of Safety for Hose and Hose Assemblies for Dispensing Flammable Liquids
Calculate total product volume in full hose
A. Standard Coax (inner product, outer vapor) ID = OD-(2*hose thickness) = 0.375
Total product volume = volume of inner hose = (pi) (ID/2)2 (
12*L)
= 13.253594 cubic inches
= 0.0076699 cubic feet
= 0.0573786 gallons