Marcohotrod
Well-Known Member
Here we have 87 89 and 93 pump gas, pumps labeled maximum of 10% ethanol. We like more octane, but to get it I think we are getting more corrosive ethanol? Anyone have any facts on octane vs ethanol content?
Pump gas octane + ethanol
- Thread starter Marcohotrod
- Start date
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Bigdummy
Not a Nova
I use Lucas additive
Marcohotrod
Well-Known Member
I use Lucas additive-it helps!
If you're looking for a general statement, its probably safe to say that up to a point, ethanol helps (MO+RO)/2 octane. If you go over to NY State and buy premium 0 Eth fuel, you'll find its 91 octane IIRC, definately not 93. My truck pinged merrily up the NY throughway hills on that stuff.
Ethanol is an oxygenator so it helps gas milage in some cars. That's the main reason its there, milage and pollution. It replaced the main additive in first attempt at 'reformulated gasoline' which was pretty horrible stuff. American (Amaco) made a very good Lead free Premium years before reformulated fuel came along. Others did too. The stuff we buy at the pump today has lots of other chemicals in it such as benzene and tulene to get the characteristics desired.
The ethanol isn't corrosive in and of itself, but doesn't play nice with many rubbers or when moist air gets in the fuel tank.
I posted some links and references in this thread mostly about distillation curves
http://racingfuelsystems.myfunforum...stics_Street_Pump_then_and_now__about579.html
You should know that some racing gasolines are available with close to 10% Eth.
So good fuel can be made with eth, its just expensive and doesn't have a long storage life.
Look up Vp Racing and Sunoco Race Fuels if you're curious.
Marcohotrod
Well-Known Member
ethanol has half the btu content that gasoline has, so it requires twice as much to go a mile. air has moisture in it, which ethanol sucks up
Bigdummy
Not a Nova
ciamcoop
Member
I was just reading about this today. They say ethanol is around 114 octane, e85 is around 106 octane. It takes around twice as much e85 to equal the same a/f ratio as 100% gas. Guys are also making more power running e85 when tuned properly. I've been out of the hot rod loop for awhile so I'm trying to catch up.
We race with E85....you need about 25 to 30% more E85 then 100% gas...and make more power...
Only thing changed on the car in the switch from gas to e85 is the carb...same steel braided line..same fuel pump...same fuel pumps....
Been racing with it for about 5 yrs now....
Only thing changed on the car in the switch from gas to e85 is the carb...same steel braided line..same fuel pump...same fuel pumps....
Been racing with it for about 5 yrs now....
Lustle
Well-Known Member
You might be thinking methanol. Ethanol has nearly 70 percent. E85 has just over 70 percent the BTU content compared to gas. Methanol is very susceptible to picking up moisture from the air. Can't store it for long without it picking up too much water. Used to work with sprint cars, we always only kept a couple thousand litres on hand at any time, to prevent contamination. E85 on the other hand is not nearly as susceptible. It will pickup moisture. But not nearly at the rate or quantity as methanol.
No. It takes around 30-35 percent E85. This is also why guys complain about mileage on E85, because you have to use 30 percent more to get the same power. E85 octane also is more like 100-105 octane. It's not as "exact" as gasoline. It's not nearly as regulated as gas, it doesn't have the quality control or measured as carefully. Especially on your average commercial level. You can go to three different E85 stations, pickup a gallon. Test it. And get 3 different octane ratings. You can repeat the test a week later and each station might read completely different from the week before. Race quality E85 is highly regulated and tested, much better quality control and such.
There's so many myths around E85 that I hate. "It eats fuel lines" Yeah, if you use 20 year old straight rubber line. E85 has been out for over a decade now. Lots of line is purpose built with it in mind. Even the over the counter fuel line. If you're so worried about it you can buy line that's specific for alcohol use. "Oh it's garbage gas, you don't get the same power" Nope, you get more! If you run it right. Putting E85 in an engine built for 87 will give you nothing but worse mileage. Just like filling the same engine with 91 non-ethanol gas doesn't add any power, just gives you a lighter wallet.
There's loads of guys out there running 14:1 (and higher) compression street engines on E85. And that's not just the fantastic octane rating. The cooling properties of E85 are very beneficial as well. Guy's have been building some crazy motors on the stuff. I wish we had an E85 pump here.
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