Hey guys would you please help me better explain something to my friend?
It’s regarding gas, octane rating and how he believes that all gas is the same regardless if it is purchased from Arco, Shell, Texaco, Chevron, or Unocal 76.
I drive a lifted 2003 F-150 Supercrew with a Magnaflow cat-back, AirForce One intake, 4.56 gears, and a custom Superchips 3-program Micro Tuner (currently programmed for 89 octane), he drives a little 4 door Scion.
I only buy gas at Unocal 76 and when possible I try to fill up at the same gas station. He thinks I am completely out of my mind and insists that 87, 89, or 91 octane from Unocal is the same quality as if it were purchased from any other gas station, and that I should be purchasing my gas from stations that are selling it the cheapest.
I need help breaking this down to him, some technical information, perhaps even some links you can point me too.
Thanks in advance for any all replies.

 

tell him that the BTU rating from diffrent brands of gas is diffrent, Mike troyer told me he has seen best results from union 76 brand gas it has the best BTU rating also the preservitives and cleaners veries by brand and plays a effect on the BTU rating also, i know there are other factors but this is this is a big one, good luck, i only run gas from the same station also, i have got good gas from chevron also

 

There are only a small number of refineries, so the fuels are most likely processed at the same place.

Now, different companies might request different blends/additives, but I'm not sure how "different" that makes the fuels of the same octane rating. The octane rating indicates the fuel's ability to resist pre-detonation.

Higher octane has slightly higher BTU/unit numbers:

http://www.vermontfuel.com/server/energy_specs.html

I've driven my truck from florida to cape cod, filling up with 87 octane at a different place each time. It ran fine the whole time.