Big Oil is forcing lower quality gasoline on the market

[happyslug]

6. When I went to Colorado in May 2013, I notice a lot of 85 Octane gasoline

I assumed it was due to higher attitude (but the next question how would lowering the Octane at higher attitude affect gasoline performance?). In my home area of Johnstown PA the lowest we see is 87 octane (Engine performance can go down as you go higher in the atmosphere, but this is do to the air having less oxygen to mix with the fuel NOT anything to do with the fuel, the the heights needed to require a different fuel mixing system is found in the Andes in South America NOT in Denver Colorado).

Thus my assumption was wrong (i.e. I assumed the lower octane could be used do to the higher attitude but that was WRONG, heights were not high enough to make a difference and the difference relates to oxygen in the air NOT the octane of the Fuel).

Now during WWII, octane was set by the US Army for its vehicles at 89 octane, the reason was simple, aircraft had been using that level of octane since 1936 (Fighters and Bombers could have up to 130 octane but the DC-3/C-47 transport engines were set to be used with 89 octane).

Prior to WWII, we had all types of Octane levels. As late as 1954, the average Octane for "Regular" in the US was 79 (Many states already required 89), but as the 1950s progressed, 89 became what most gasoline makers aimed for (Automobile engines were increasingly designed for 87, to give them a 2 octane knock safety net).

When the 1960s hit, you had cars designed to use up to 130 octane, but with the switch to unleaded gasoline in 1974, 87 became the low for most "Regular" gasoline in the US.

Remember the higher the octane, the more powerful you can make the engine (Mostly by increasing pressure within the engine via the Carburetor, Turbo-Charger or Super-Charger in the short term, in the long term just designing the engine around that higher octane number).

Higher octane, by itself can NOT make the engine more powerful, but once you have higher octane fuel, you can design the engine and its fuel system around the higher octane fuel to produce more power.

Lowering the Octane of the fuel, requires similar changes to the engine and its fuel intake systems, this time to reflect that the fuel is NOT as rich (and thus the engine has to be made less powerful).