Does anyone know if 93 octane fuel contains ethanol? Every pump I go to in SC and FL says that the fuel contains ethanol. Now I understand that 93 Octane does not contain ethanol.

So if I can't find ethanol free fuel....then what?

 

All fuel contains a certain amount of ethanol. More than likely what you are seeing at the pumps is a tag that says the fuel may contain up to 10% ethanol. From what I have been told it is nothing to worry about.

 

10% Ethanol changes the stoich of your fuel from 14.68 on gas, to around 14.1 on gasohol.

Ethanol gives you less MPG and has less HP because it doesnt have the same BTU content as gasoline. Less BTUs means you have to use more fuel to make the same power.

Ive checked Ehtonal content at a few gas stations and they are always at 10-12%. They always will, ethanol is cheaper than gas. The more ethanol they add the more money they make.....

 

thanks.

 

93 octane can have ethanol or not. Look on the pumps, by law there has to be a sticker stating that their fuel contains ethanol and at whatever percentage. If there is no sticker, there is no ethanol.

Ethanol, corn alcohol, moonshine...whatever you want to call it, has an octane rating of 116. When you go fill up your tank with 93 octane with 10% ethanol, what you are really getting is 89 octane fuel that has had an octane booster added (ethanol @ 116 octane) which lowers your MPG by about 2 1/2.

In other words, you are paying 10 to 13 cents more per gallon for 90% of a lower grade of fuel (89 octane) that has been cut with an inexpensive octane booster that makes your car get about 2 1/2 MPG lower fuel mileage.

On the other hand, E85 has an octane rating of about 105. Get your car tuned for it and it will be a beast, but your fuel mileage will be cut by nearly 35%. Sacrifices .

 

The BP station where I trade has up to 10% ethanol in regular gas ONLY. Most other stations in town have up to 10% ethanol in ALL grades of gasoline.

 

Gas is 2.75 for 91 here and 2.19 for e85 at 105 octane. Yes gallon for gallon it makes less HP but so does every race fuel out there. You burn more of it to make more HP than gasoline.. You gain about 30rwhp on a typical head/cam corvette. While power per gallon drops, you are burning more of it. In the end the only thing you lose is the range you can travel on a tank of gas.

Once an engine is purpose built for 105 octane, it will gain all the economy back plus another 30+hp from 2 points compression and spark advance.

The reasons for ethanol are to save our planet, have a cleaner engine, and decrease dependency of foreign oil....even if it cost the same.

 

Well said Spin. Although I don't always completely understand your computations I have learned a great deal by reading your threads/posts. Thanks for taking time to educate us on the various aspects of the C6 vette.

 

All gasoline grades in the Houston area have 10% ethanol to aid emissions compliance for our region. Ethanol was added to replace MTBE when it was outlawed as a ground water contaminant from leaky buried gas tanks. Ethanol adds oxygenates to the fuel to reduce emissions (NOX??).

 

whether the fuel has ethanol in it or not, e10 does not have any more octane in it than pure 93 octane. does that make sense, nope, but all the e10 gives us is lower mpg. maybe you get a cooler charge from the ethanol, but no octane boost.

e85, yes.

-Carl

 

In theory....

I don't know that it is cheaper overall. I think it raises the prices of everything else we buy because feed for livestock goes up as it becomes less available. The costs just get passed back to us...

Most of us dont run 12:1+ compression anyways to need the higher octane.

 

This is debatable. If it wasn't for the government subsidies, ethanol couldn't survive. Studies have also shown that it burns more petroleum to make the ethanol and get it to market than it saves. For example, you can't ship ethanol in a pipeline so it has to be railed or trucked. And it all comes out of the midwest.

 

It is all about politics and which lobby gets favored by the government dole.

 

It depends totally on where you live. Some states still carry gas without ethanol in it and some places have no-ethanol only in the premium gas. And many stations don't even really know what goes in their tanks, it just depends on what is delivered, so you can't really even trust the attendants to know if they have ethanol or not.

I seem to recall hearing that there is federal legislation that kicks in this year or next making it mandatory in all states and all gas in all 50 states.

 

If you dont retune for the advantage E85 offers from being 105 octane, there is no HP gain. It is demonstrated on any car tuned for it. Higher octane allows a leaner burn with more ignition timing and even a bone stock car gains from its use.

E10 does not give lower MPG. It burns cleaner.

 

Tuners have posted the gains from higher octane tunes. Running higher octane in our cars is demonstrated widely by both retuning for torco and for Meth injection. Both have 20+ gains in bone stock vettes and 50+ with FI cars. E85 is widely used on imports as the sole fuel due to its cars being able to get more fuel pump into the car. Politics has nothing to do with the fact that octane boost shows gains.

The very reason we arent paying 5 bucks a gallon like every other country is due to E10 and the threat of increasing its percentage if prices get out of hand.

 

Typical of the misinfo that flys around the net, if you take a bone stock car and tune it as best it can be tuned on 93, that same car will make 18-22rwhp more tuned for E85 because the car can run more timing with the higher octane. I have never seen a pump gas car able to run more than 21 degrees peak timing whne its leaned out to 13:1. E85 will let that go to over 30 degrees without timing being pulled. No power gains are seen past 28 or so but it does make more power going between 21 degrees and 28 degrees.

Charlie at RPM has tuned many cars with torco and Meth injection that are running the stock H/C and gained over 20rwhp from it. One such car belongs to forum member JBSblown. His stock H/C car with bolt-ons made such gains and it isnt 12:1 compression.

I have done this conversion and have run octane boost, straightE85, or meth injection on stock H/C cars and see gains typical of tyhis all the time. You may want to revise your posts if you havent done factual tests yourself to disprove what youre spreading around.

Here is a magazine test on a corvette with the tune done at LG motorsports to show the gains on a near stock car:
http://www.vetteweb.com/tech/vemp_08...t_results.html

Personally I think meth injection is the best option because it cools the intake charge lowering IAT's resulting in more power than the other two. It also is only used when the car is under load requiring little to no effort in running so you dont have to hunt for E85 vendors or run into fuel sytem capacity issues. Its cheap at 400-500 for a system, takes little time to install and is 116+ octane.

Here is a post on its use which includes other N/A users who factually gained 25rwhp on the dyno when they retuned with it.
http://forums.corvetteforum.com/c6-t...lications.html


So in summary, YOUR CAR will gain from octane boost, meth injection, or E85 use. At nearly 11:1 compression with an early closing intake valve, the tune it can run on 93 cant be optimum for power due to octane deficiency. As far as the cost, it gets tiring listen to people make statements like 'it gets passed back to us'. If thats true sir they are passed back to you even if you use straight gasoline because the sum net costs are here in the country even if you choose not to use it. Its made and sold to someone and you not buying it doesnt make it 'not made'. As a 105 octane fuel you cant compare it to 93 whcih is exactly the same cost. Cars will eventually run it just as unleaded fuel was forced on us. One day all cars will run it. It runs better, has better throttle response, and burns cleaner.

I welcome it.

 

My cynical comment had nothing to do with performance. Your points are certainly valid regarding performance. My point was concerning the true cost of ethanol which is heavily subsidized by the government. Then again there are those that could make the point that oil and gas is heavily subsidized by the government as well.