ethanol free vs top tier

[MagnumForceGB]

My car is a weird one, I have to run 91 octane due to the supercharger, but E10 gas provides better timing than E0. I can get about 4 degrees more of timing with E10.

11.3:1 compression ratio with 10 PSI boost sucks for trying to get the best performance. If you have a datalogger (IE: Kiwi Bluetooth) you can see how your car handles timing at WOT.

[White_SS/RS]

Originally Posted by MagnumForceGB

My car is a weird one, I have to run 91 octane due to the supercharger, but E10 gas provides better timing than E0. I can get about 4 degrees more of timing with E10.

11.3:1 compression ratio with 10 PSI boost sucks for trying to get the best performance. If you have a datalogger (IE: Kiwi Bluetooth) you can see how your car handles timing at WOT.

Ethanol responds well to higher compression ratios and your seeing more timing because it burns slightly slower than gas.

[White_SS/RS]

Originally Posted by OK2DRUL

I always use top tier premium fuels and nothing else. The ethanol is added to modern fuels because it makes the gas ignite and burn hotter. This in turn gives better fuel economy and is cleaner on your fuel system. I don't add anything to my fuel ever. Never used a catch can and don't have any oil in my throttle body ever. Ethanol free gas is meant for carbureted engines that can't handle the ethanol additive. You won't see any benefit with using ethanol free fuel and will pay substantially more to do so.

Originally Posted by Rabbitlfx

I think you have your facts wrong, if ethanol increases fuel economy than why do E85 vehicles get 40 percent worse fuel economy running E85 than they do runnning 10 percent ethanol. Stop by your chevy dealer and check out an E85 window sticker. Ethanol is a hairbrained idea to try to reduce our dependece on foregn oil. By adding 1 gallon of ethanol to 10 gallons os gas you improve your vehicles range, but you do this at a cost. 10 gal of gas 125,000btu's * 10 = 1,250,000 btu's
1 gal of ethanol 85,000btu's added together = 1,335,000 total btu's
11 gal gas = 1,375,000 btu's
doesnt seem like much but the more ethanol used the less power and fuel economy you are going to have. Want power out of ethanol, add a blower and lots and lots of fuel.

Rabbitlfx has got this nailed. It should also be noted that Ethanol doesn't burn hot, in fact it burns much cooler than gasoline hence the lower BTU difference.

Its my belief that Ethanol (up to 10%) is added to fuel to reduce NOx levels seen during extemely high combustion temps. Its an emission control measure!

Now the benifits of Ethanol... E85 usually carries an octane rating around 106, it runs cool, its condusive to much higher compression ratios 12+:1... so, should an engine be designed specifically to take advantage of that and you could look past the horrible mileage. Ethanol products make an awesome cheap performace fuel.

[axis]

Ethanol free 93 gas is better than E10 93, plain and simple. There's more energy potential in pure gas vs ethanol blend in the same volume of fuel. There are benefits to E85 if tuned properly for it and especially in FI vehicles as explained above. Those benefits DO NOT include better gas mileage. You get much worse. I've seen reports of 30-40% worse. That means you'd need to get E85 for around $2/gallon to make it cost efficient. Most can only get the E10 blend so that's all we have to work with. Also, ethanol free 93 is more expensive than E10 93.

[MagnumForceGB]

Originally Posted by White_SS/RS

Ethanol responds well to higher compression ratios and your seeing more timing because it burns slightly slower than gas.

I took a lot of datalogs to figure this out, too bad other V6's locally won't listen and run embarrassing times at the track.

I'm actually up 8 degrees more timing now, colder plugs, all the 100% gas out and a more accurate IAT. The Kiwi Bluetooth device with the Torque app has been worth the price, really helps to see what the engine is saying.

The V6 can run 87 octane even while having a 11.3:1 compression ratio due to direct injection, but I think to get the most power (ie: timing) at WOT you need something that can resist detonating.

[redredrage]

At the end of the day most gas has ethanol and the fact is that its cheaper over all. Thats a solid fact because the engine adjusts to add more fuel as a result of the o2 sensor.

What you didnt know is that as a result of the ethanol is that youre getting more power. The calculations been done, less btus per volume, but because more fuel is added (enyough to counter the lower btu per volume) you get more power.

Where it gets fun is adding 5 gallons of e85 with 11 gallons of 89. I just saved $5 overall and added 20 wheel horse as well as polute the enviorment less than a prius. And thats with no mods.

Oh if you have a v6 i wouldnt recomend adding e85 without mods.... the ls3 v8 is simpler and o2 sensors as well as fuel system can handle it.