'72 Chevy - no ethanol or 91 octane, which is better?

Ever since unleaded gas came out, they changed the formula for computing the octane rating. Comparing the two is like comparing apples and oranges.

Once your old stations with repair bays were phased out, the oil companies became interested only in selling as much gas as possible. Some genius at one of them came up with the "Pool Margin" concept. You took the average monthly thru-put of the 3 grades and applied a formula which gave you X cents profilt per gallon of gas. The oil company salesman suggested to you what that profit should be. It was achieved by using regular gas almost as a loss leader and addng the difference to the higher grades so it all averaged out. You were under no obligation to follow the recommendations, however they started building strategically located company stations to control prices within a market.

 

I like apples and oranges. They both grow around here and are fruit.

company stations control prices within a market----- -Which means we are screwed!

 

I try to run ethanol free premium in my carbed engines. And the little motors, snowblower, outboard etc.
The newer ones have all those sensors that let the computer adjust the timing and whatnot to make your engine think it's running ok when it would really be running like crap.
The Fairmont runs so much better on pure gas.

 

How easy is this to find in your area, and how does the cost compare? When the few stations that had it around here were carrying pure gasoline, it was available only in the regular grade, not premium.

 

Same here and legally, or supposedly according to the signs, it can only be used in boats, or by Marines.

 

Shell Premium and a Co-op Brand up here.
Here's a website:
http://pure-gas.org/

 

Go to the paint store and buy a gallon of toluene. Add it to you full tank. Best mix is 25 to 30% toluene to gasoline for performance, but a gallon in a full tank of say, 16 gallons will make a world of difference in stopping pinging and will clean the carbon off the valves and pistons. It won't do any harm either. Toluene is what the oil companies add to gasoline during certain times of the year or to up the level of octane. It works by raising the temperature at which gasoline will auto-ignite. (PINGING) and allows you to run more ignition timing. This will increase power and mileage in any engine.
Try it. I think you'll be pleasantly surprised.
Good luck.
Dave

 

The WAWAs around here offer non-ethanol gas. If the price of regular 87 is $2.57, the real gas is about $2.99.

I would run non-ethanol gas in any engine made before ethanol was introduced into gas. Whatever you do, do not run E85 in anything except those cars labeled for use.