IS350atWOT

iTrader: (1)

I have noticed a couple of local gas stations that are selling ethanol-free gas. They are about the same price as other stations too. So I was wondering on whether or not to switch. Gas mileage is easy to test. But what about long term damage of ethanol? Does ethanol-free give more horsepower in the F?

Mitch08ISF

iTrader: (8)

e85 was proven to run leaner under 100% throttle with the F, but I wouldnt imagine the 10% most companies are adding to fuel could do any harm. If we could tune our car sure it should give a few extra whp over 91-94octane as e85 is rated at 105-108, but as of now we are stuck. I do however believe that if you never went full throttle you could most likely run e85 in the F with 0 issues. I ran through several partial tank mixtures with 0 issues.

crazymikie

Over time, the mixture would richen up since ethanol has a different stoichiometric ratio than gasoline does. IIRC, stoich is 10:1 as opposed to gasoline which is 14.7:1. While running in closed loop, the oxygen sensor should adjust the trims to account for this, and then the long term trims would be applied to the open loop fueling as well.

That being said, if your car isn't designed for e85 and doesn't have the necessary flex fuel equipment, then you shouldn't be running e85 in it since the system doesn't have enough adjustment to compensate for the fuel.

Running e10 (all stations in the northeast sell e10- you can't get straight gasoline anymore) is fine in newer cars. I think e10 can cause problems if you have a carburetor or if your car wasn't designed to handle it, but newer vehicles should all be able to run on e10 just fine.

Dv8tion388

iTrader: (2)

Ethanol free gas??

I dont get it. Is it to extend MPG? Enviro concerns? Why wouldnt you want ethanol in your fuel?
My race car runs on 85% ethanol for the amazing temp reduction and ability to advance timing which all = a lot more power at the price of pump gas.

Isn't the % of ethanol they put in regular fuel, like a filler so gas isnt even more $$?

~Dv8

tenspeed

iTrader: (1)

It might be bogus but I was listening to my local talk radio about a hour ago and the host was having a problem with his new lawn mower. He bought it last year and it would not start this year. Some callers said the it was the Ethanol in the gas causing damage to the rubber gaskets in the fuel system. They also said to only use as much gas as you need and store the machine dry. Another caller said it was a problem with boat engines and two cycle machines like chain saws and weed wackers.

I don't know if it's valid or not. The radio is full of junk science like the internet. Maybe a query to Lexus would provide the best answer. I'm in western NY and all gas has 10% ethanol....

crazymikie

I wasn't including yard equipment when I said vehicles I agree- you should always dump the gas from lawn equipment when you are going to store it for a while. I think it will gum up the needs in the carb.

Luckily, vehicles these days are fuel injected, so it's a non-issue.

e10 reduces pollution, but it also kills gas mileage.

crazymikie

No- the government subsidizes the corn and grain farmers, so the ethanol is usually cheaper. e85 used to be < $2/gallon not long ago. The problem is the price of grain related foods like bread go up since the farmers make more money selling grain to make ethanol for e85.

You make more power with ethanol at the expense of worse fuel economy.

lobuxracer

iTrader: (2)

Advancing timing to make power just means your combustion chamber design is pathetic. Peak pressure needs to be 7 - 8 degrees ATDC, so whatever timing makes that happen is what makes best power. Better designs need LESS advance because the fuel burns more quickly and more completely. Some of the best designs have less than 10 degree full advance because the combustion chamber is very efficient.

No alcohol makes inherently more power. Properly tuned you can make more power on any alcohol because the heat required to vaporize alcohol is higher so you get more detonation resistance compared to gasoline. What this really means is you can run more compression with an alcohol engine than you can with a gasoline engine. Compression is one of the magic three C's for power, so if you do everything optimized for alcohol, you can make more power from the same displacement.

Alcohol attacks buna-n, the standard cheap o-ring polymer. This means your seals will swell and eventually disintegrate over time. More expensive polymers are used on flex-fuel and alcohol only engines. Alcohol also brings H2O to the party so corrosion in an alcohol fuel system is a much larger concern. If viton were cheap, we'd all have no worries, but viton is expensive compared to buna-n, and car manufacturers make decisions over pennies. So fuel systems are designed with the cheapest seal they expect to work with the range of fuels the engine will see over its life time.

As an example - there is a ton of sketchy BS on the web about the virtues of adding acetone in very small quantities to your gasoline. The claims are it acts like a surfactant to reduce the fuel droplet size and increase the engine's efficiency. I also read acetone will attack the seals in the fuel system and cause them to deteriorate over time. So I took some old injector seals from my Supra (I blueprinted the injectors at about 140k miles) and soaked them in pure acetone. After about a week, they were so swollen, it would be impossible for me to use them again. So whatever Toyota used in 1993 did not like pure acetone for a week.

Since no one is trying to run their engine exclusively on acetone, it's probably not such a big deal, but it was interesting. So, given a 10% solution of ethanol, what could legitimately be expected, especially from older cars where alcohol was not even being considered? In a realistic sense, not much. They'll likely be fine. It's not like when they took the lead out of the fuel and started having issues with valve recession into the head. But if you're purist, more than likely, you'll be upset about the possibility of something going wrong because of the evil alcohol.

I'd love to buy gasoline without alcohol in it. With a 10% ethanol mix, you get 96% of the power per unit volume as you do with "pure" gasoline (which really isn't pure at all, it's a bizarre cocktail of hydrocarbons, most of them ending in -ane), so I'll get better miles per gallon, and since fuel is sold by gallons and not by weight, I'll spend less to go somewhere. Of course we should be selling fuel by weight not volume, but that's a completely different rant.

If there's anything magic you want to add to your fuel, it's oxygen. Even a tiny shot of nitromethane will convince anyone there's value in bringing your own oxygen to the party!

crazymikie

I ran a mix of nitromethane, methanol and water injection on my old WRX. It was AWESOME. I was running 30+ psi without any signs of detonation on a Japanese spec motor. I think that was the fastest car I've ever driven...3300 lbs and making almost 400 whp.

IS350atWOT

iTrader: (1)

Thanks everyone for the great feedback! I think I'll try a tank or two of the ethanol-free gas (Citgo) and see if I notice differences of gas mileage and power. I'll let everyone know the results later on.

Dx3

iTrader: (13)

I only use ethanol-free gas in all my cars/motorcycle. Granted, I have to drive further to get it, and it's usually a little more expensive. But, I have noticed a sizeable difference in mpg with 100% as opposed to 10% ethanol...

crazymikie

You're lucky- In the People's Republic of mASSachusetts, they only sell e10.

IS350atWOT

iTrader: (1)

Well the verdict is in. I ran a couple of ethanol-free tanks through my F. I didn't find any advantages on daily driving. Now that I'm back to e10, I notice more power, that's for sure. The F seemed "heavy" on pure gas.

IceIridium

iTrader: (2)

The local Chevrons here have 87/89/91 octane on one pump and 94 octane on another pump. The 87/89/91 are labelled "up to 10% ethanol" and the 94 is labelled "contains no ethanol". I was recommended to only get 94 oc for the IS-F (paying a buck fifty per liter for it ) and was told the no ethanol was a good thing. ...I was like, "oh ok."...



So should I try a coupl'a tanks of 91 and see how it goes?

crazymikie

That kind of makes sense. The non-alcohol gas probably caused your trims to lean out the mixture in closed loop operation and then when you went to e10, your car was essentially leaned out a bit. My guess is that it will go back to feeling the same way after a couple of tanks and the fueling trims are relearned on the new gas.

Did you notice any differences in fuel economy?