thanks guys. i realize higher octane will not yield higher FE. my thought and hope was that i could test gas w/out ethanol.

i changed vehicles just as E10 was getting integrated locally, so i was not able to test the theory of higher FE w/ straight gas.

Ah interesting, I wonder how 100 Oct reacts to fuel warmer and the other old 'tricks' that supposedly only the 'older' fuel blends without alcohol worked with. When I think of 100 Octane I feel like I'm using pure gasoline without additives from the 60s or something (it's a nerousis I have :p), but I suppose it probably has just as many detergents and things to decrease the volatility. Anyone know?

As for E10, look at Jay's thread on testing Ethanol content, you may be running E6 and just might find a spot with E0 to properly perform your test with.

Or get a 15 gallon drum, put 2 gallons of water in the bottom, 13 gallons of gas and let the alcohol separate out, and siphon off the "pure" gasoline...

-Jay

Higher octane won't help the FE and will also make the car feel sluggish.

I run Sunoco 100 oct and 109 oct unleaded in my Fiero on a regular basis. I run a different tune and boost level when running race gas. The car is very sluggish running race gas on a 93 octane tune.

ok, i'm gonna fill up on sat or sun. if that station still has race fuel, i'll test it 50/50 with 87 octane. any other warnings, please make it known.

This is starting to remind me of that episode of Family Guy where Peter puts airplane fuel in his pickup and imagines that he's flying...

https://familyguy.wikia.com/wiki/Airport_'07/References

Don't laugh. My uncle put jet fuel in his Ford Windstar thinking it would run better. It ran like crap. I think it would have run better on kerosene. :rolleyes:

-Jay

100 octane fuel isn't going to be leaded for the cost that is talked about.

Some of the 100 octane unleaded fuels are designed to be spec fuels. Often, they don't perform as well as even an E10 blended fuel. I used to sell racing fuel to racers and shops, and there was a shop I worked with that would cut some of the common unleaded fuels with unleaded pump street gas to develop more power. That was in a time when we were getting MTBE as an oxygenate in pump gas, and MTBE is also an oxygenate in oxygenated leaded and unleaded racing fuels.

Final trick about racing fuels is this: If it's coming out of an unsealed container, I won't use it. Transportation in different tanks, storage, etc. corrupts the fuel with what was in it prior and with contaminates, water, rust, etc. So, it's a crap shoot.

You don't want to use a leaded racing fuel in anything with a cat. It'll trash it in addition to plating the O2 sensor. Cat will get ruined far quicker.

Finally, how a fuel is built/combined is different from one brand to another. Octane can be developed from different combinations of chemicals. Not just the chemical, but even the order in which it is added. This affects specific gravity, which affects carbureted engines a lot more than fuel injected vehicles, Reid Vapor Pressure, the initial tune, final tune, and the end output. Yeah, one fuel of 110 octane can have more power than another manufacturer's 110 octane fuel in the same engine.

As far as I know, Jet A is a kerosene-based fuel, while Jet B is a kerosene and gasoline mixture. Jet B is used primarily in cold climates. In theory, a car that burns gasoline should at least run somewhat on Jet B, but not Jet A (running Jet A in a gasoline engine would be like filling your tank with diesel). However, it would probably (among other things) ping REALLY badly, since jet fuel does not need to (and, therefore probably woudn't) have a high octane rating. On the other hand, a diesel engine should run fine on Jet A. And MANY airports run fuel trucks and other such vehicles on jet fuel in order to simplify things in terms of needing different kinds of fuels.

I would venture to say that since he dumped some in the tank, even if it was A to begin with, it ended up being B from mixing with the fuel already in the tank. It was a bright idea he had one day with the help of his friends Jose Cuervo & Jack Daniels. ;)

-Jay