I just found out there is a petro station near my home
selling 90 octane no ethanol fuel. Should I switch to that
or stay the 93 octane 10% ethanol I have been using? By the way
the no ethanol is about $1 a gallon more than the 93 octane. Would
like to hear from evil twin if he sees this

 

No way on the octane diff then 1.00 per gallon more also, NO. I do put no ethanol in my car but it is sunoco 93 but I only pay about 40 cents more for that per gallon... Robert

 

Personally I'd stick with 93/10. I'm not sure why everyone gets bent out of shape over the 10% ethanol.

 

Wish it was available here

 

93/10 is fine.. its not E85.
Adding ethanol to gasoline in lower percentages, such as 10 percent ethanol and 90 percent gasoline (E10), reduces carbon monoxide emissions from the gasoline. The cost of E10 in gasoline is about 2 to 3 octane points. No reason to spend 1.00 a gallon extra for non ethanol fuel
Bill aka ET

 

Thanks again for your input

 

I never thought it was the low percentage of ethanol (10%) that was the problem, but that when it sits in a stations tank that there are issues with it separating and you actually getting a much different percentage than the 10 claimed. Anyone else hear that? Also it sucks up a lot of moisture from the atmosphere so if its an old station you can get a bunch of water in the fuel.

 

Just based on some reading (whether it's true or not) it sounds like after 90-120 days it starts separating. I'm fairly certain most gas stations get a refill once every week or two so that's a non-issue.

 

That is the reason for completely topping off your fuel tank when you put it up for the winter.This helps to prevent the fuel from soaking up moisture.
Fred

 

pure ethanol has a high octane number, but it has a high separation value when mixed with gasoline. it also has the ability to absorb water. 10%E is OK in my book, but I would cringe at the need to use E85. Too many possible variation in reliability.

 

I remember a post a while back that said you're gas mileage and performance is not as good with 10% ethonal.
So if you pay a bit more you may get back the performance and better gas mileage.
The result is about the same for the dollar so they say.
I figure that if this is true, then I would rather have the "better" gas and reduce the risk of water problems in the gas that may mess up your sending unit.
I had to replace one once.

 

I have heard that as well and it may very well be true, but I've yet to notice a noticeable difference in performance. Let's put it this way. I've been using 89/10 in my DD cars for the last 6+ years. I have exceeded the EPA rated highway miles on each and every one of my cars all using the 89/10 blend. There may be some truth to what is said but but I have yet to see any adverse affects. There are too many driving variables and maybe under exact same conditions pure gasoline may give better mileage. Needless to say I'm happy with my results.

Personal Bests:

'99 Grand Am GT - Rated 29 mpg hwy, personal best 33 mpg
'06 Mazda 3 - Rated 31 mpg hwy, personal best 35 mpg
'09 Malibu - Rated 33 mpg hwy, personal best 38 mpg

 

The problem with low octane fuel is detonation. Unless you live in a high altitude area, detonation is critical. No you don't have to hear or feel it.
you mentioned good fuel economy, but are any of these motors seeing 200/300,000 miles. low octane fuel in an LSX engine causes wrist pin damage, engine knock, connecting rod and main bearing damage one very evident thing we found in two years of testing was low octane fuel in an LSX engine cause #7 piston to deteriorate. Many people think that if the engine does not blow up in 100,000 miles that what they are doing is ok. You don't put lawn mower gas in a high compression engine. You need octane to make sure the piston makes it to the top of the stroke. 89/87 octane in a high compression engine will never accomplish that. You want the spark to cause ignition not the compression of the engine, Unless you retarded the spark enough to allow for proper detonation , but at a definite disadvantage in performance. Taking timing off an engine reduces HP , just like advancing timing increases it. Having the engine knock sensors back off the timing reduces performance, but also the engine has to knock to accomplish this. engine knock reduces engine life. 87/89 octane causes engine knock under load, in a high compression engine like an LSX. Its OK to use this in order to get you to a station that has the proper fuel. Its not designed to be used daily.

 

I'm using 93/10 in the Vette. All my other cars have used 89/10. I was just stating that I've used e10 blend for years and have noticed no problems. I won't use anything less than 91 in the Vette.

 

91 is good except at sea level and when its very hot ambient temp. That's why I recommend if you can get 93 get it, for me the difference between 91 and 93 here in the North east is 4 cents a gallon. 91 will actually performs better than 93 as long as there is no detonation, octane reduces hp, but detonation reduces hp even more but with the added cost of reduced engine life. I*ll take the insurance of higher octane over the HP gain of lower octane fuel any day.

 

Ethanol was a government sponsored plan to reduce the amount of imported oil. Ethanol has only about 80% of the energy compared to an equivalent amount of gasoline. That's why your mileage has to suffer. The worst thing about Ethanol is it's affinity for water and subsequent corrosion. As a Chemical Engineer, I wouldn't use gas containing Ethanol unless I was desperate.

 

Keep running the 93/10 - it won't hurt anything.