One of the large Sheetz gas stations was remodeled recently, and I stopped by for the first time since then. They now have at least one pump with Ethanol free, 90 octane gas! I need 89 octane to keep from knocking at shutdown, so this is perfect for me. Most ethanol free pumps I've run across only carry 87 octane. Now I don't have to worry about the rubber lines swelling and cracking. I had converted all the carburetor inerds to be compatible with ethanol but this should make the entire system worry free. Today is a beautiful day here. I'll be driving my slick almost every day until we get below freezing.

 

I'm glad for your discovery; I hope it works.

I use the expensive 94 gas because the lower-octane products hereabouts all have 10% ethanol. I don't really know if the extra money I'm spending is preventing the carb from rotting, but I do know this - if I don't run the truck for a few days, the engine reacts to my attempt to start it as if the fuel has evaporated from the float bowl. If used daily, it flashes instantly.

Let us know if you notice a similar problem with the new fuel.

Eric

 

This is typical of ethanol fuels. They boil at a lower temp. When you shut down the heat transfers to the carb. I could watch this happen on my 223 that has a glass bowl Holley. Old fuel had additives to help prevent this. A good phenolic spacer under the carb helps eliminate this, I did it on all 3 of my engines. Ethanol fuel also evaporates faster and not much you can do about that.

 

Agree with the spacer. They cure a lot of hot restart problems also. I don't mind the ethanol it adds oxygen to the fuel and ups the octane a little. If you have fuel injection switching from ethanol blend to no ethanol isn't a problem but with a carb it takes a slightly different tune for each one.

 

Last year my friend bought an ethanol test kit, we found regular 87 octane gas at 10% and premium 91% at 8%. But here in the land of fruits and nuts we have a different gas blends then the other 49 states. And considering what it does to rubber fuel parts I hate the crap

 

As long as you buy a name brand made in the USA hose that says SAE 30R on it. It will be compatible with even 100% ethanol. The quality rebuild kits all have ethanol compatible parts in them nowadays.
You are correct about there being different amounts of ethanol in different grades of fuel. We checked some supposedly ethanol free gas and it still had 3% in it.
I think if you buy quality name brand gas you are more likely to get a good additive package with a consistent amount of ethanol.
Or if you really want ethanol free leaded gas go to your local airport and buy some 100 LL. Of course it's going to cost $5 or $6 a gallon. But it never goes bad. We pumped out an underground tank on a farmers airstrip that hadn't been used in 15 years and the gas looked and smelled like new.

 

Ethanol kits are available for some carbs but not all. Same with many fuel pumps. I changed all the hoses long ago. The days of buying Av gas at the airport ended years ago here in Calif. and that would get expensive for me, I can burn up a $60 tank of gas in one day and I do that a few times a month.

 

Real gas has more energy density than ethanol, so the jets can be slightly smaller, and should get better mileage. I was pretty disappointed with the poor mileage (10.5 mpg) I got on my trip to North Carolina over the labor day weekend, approximately 500 miles each way, and on the way down I took back roads. I'm planning to drive to Texas this Friday (1500 mile trip), and I can't count on finding ethanol free gas everywhere along the way, so I'm not going to try re-jetting the carb before I head out.

I don't have a problem with the fuel evaporating for about 3 or 4 days depending on the weather, which has been spectacular lately. The engine just fires right up almost instantly without even needing the choke.

The 90 octane immediately put a stop to the dieseling at shutdown. Normally I buy 89 octane 10% ethanol, which runs just fine. My engine didn't like the 87 octane ethanol free gas I found in Virginia. I might bring 10 gallons of extra 90 octane with me so I can see what I get on the freeway. It takes almost 2 hours of drive time to get to the interstate from my house, and the starting and stopping at red lights is almost certainly detrimental to mileage.

 

I have a difference in evaporation between two engines, one with an Autolite 4100 goes dry in about 4 days, the other has a Holley that is good for up to 2 weeks.. I've gone up one jet size in all my carbs. Ethanol fuel has less BTU's so mileage will always be less compared to Ethanol free.

 

10 gallons of extra 90 octane with me so I can see what I get on the freeway. It takes almost 2 hours of drive time to get to the interstate from my house

I cant drive ten minutes in any direction without at least crossing a freeway, so most of my driving is on the freeway. With an overdrive transmission and extensive carb tuning (via wideband AF) in the last couple of tanks I got 10.5 MPG. Of course, I do have a lead foot. That being said, Though I might miss the convenience of the freeways, Being two hours away from them sounds like an idyllic place to live!

 

To give you an idea of how rural this area is, I caught one of my neighbors snooping around a few days ago.

 

I love e10, use it exclusively in my old cars and trucks. The added alcohol keeps everything super clean and alcohol burns colder so it helps keep the engine cool. Never had any issue with rubber parts, ethanol has been around long enough that commonly available fuel hose is pretty much all compatible with it by now. The owners manuals of my factory carbureted cars from the 80's say that e10 is fine to use and won't void the warranty. After 75k miles of running e10, the carbs from my VW still looked new inside when I took them off to upgrade to bigger carbs.

E10 also doesnt' have enough difference in btu to make a noticeable change in mpg or power compared to 100% gas, and "E10" isn't always full 10% so the difference would be even less.

100% gas- 114,000 btu/gal
100% alcohol- 76,100 btu/gal
E10- 111,836 btu/gal

So e10 has about 98% of the btu that pure gas has, and if it's not full 10% ethanol then it's even closer to the btu of pure gas. A 2% difference in volume to get the same btu is not enough to rejet for. The only time ethanol causes problems is from storing it in a humid environment- it can absorb water which will cause corrosion.


BTU info taken from here-

https://en.wikipedia.org/wiki/Gasoli...lon_equivalent