6.0 on 87 Fuel

[REW]

Doesn't ethanol actually increase the octane rating? I have a few buddies that have high compression quads that run E85 because it is around 105 octane. Granted they burn more fuel now because they had to increase the jet sizes. And the exhaust smells funny! I get that the BTU is actually lower, but wouldn't that help the detonation issue? I don't like running it in anything, because it gums up and is hard on the fuel system. But, not many places around here have fuel without it.

Ethanol does raise the octain rating but that is all it does. The BTU's are lower and it is real hard on the fuel system especially in a humid (read marine) environment. If you take a cup of water and a cup of ethanol and put them together you will have less than 2 cups of liquid as the ethanol holds water in suspension. It is a neat majic trick unless it happens in your fuel system.

[MLA]

The term "Premium" is a retail nomenclature given to the more expensive higher octane fuel. Its purely marketing. Although everybody pulls from the same pipeline at the end of the line, each brand will add some proprietary additives to their fuels in order to set them apart from the other brands. There is only a small advantage to these extra additives over a so called off-brand gas, as the Feds require a certain level of additives to be added to every gallon of fuel refined. In most cases, the brand name companies advertise this special stuff they put in their "Premium" which make it so much better the plan old cheap stuff. If you peel back a couple layers of fine print, you will probably find that those special additives are put in all their grades.

The fuel's octane level is not an indication of its quality. Its not an indication of its power output or fuel economy. The brand name and sometimes higher price is not even an indicator of its quality. The quality of the gas will be based more on how the station maintains their tanks and pumps and how long the gas has sat in the tanks. In less populated areas, the higher grades can actually sit for quite awhile because its not purchased as much as regular grade.

[MLA]

E85 is 85% ethanol and is quite differnt from what you get out of a pump that states "Up to 10% ehtanol" You do not want to fill your tank with E85 if you do not have an E85 or Flex-Fuel built vehicle. Ethanol blended fuels are safe to use in anything built in past number of years, even most boats.

[mrnate450r]

E85 is 85% ethanol and is quite differnt from what you get out of a pump that states "Up to 10% ehtanol" You do not want to fill your tank with E85 if you do not have an E85 or Flex-Fuel built vehicle. Ethanol blended fuels are safe to use in anything built in past number of years, even most boats.

I get that there is a major difference, and even though my Tahoe is a flex fuel I likely will never run E85. My concern is that the ethanol is added to lower quality fuel to increase the octane rating? Granted, fuel quality has gotten significantly better in the last few decades as well as oil as far as that goes. Sorry for the hijack!

[MLA]

I get that there is a major difference, and even though my Tahoe is a flex fuel I likely will never run E85. My concern is that the ethanol is added to lower quality fuel to increase the octane rating? Granted, fuel quality has gotten significantly better in the last few decades as well as oil as far as that goes. Sorry for the hijack!

Push aside every thing you have ever heard from a gasoline commercial. Its all marking and is misleading. Octane and gasoline quality are two different subject and are not related.

Now, picture a see-saw. On one end, is seated Billy Octane and on the other end if Franky Volatility. When Billy goes up, Franky comes down and when Franky goes up, Billy comes down and Jane Quality is over on the slide by her self.

Ethanol is added to regular unleaded because it A) takes up space in the tanks, which means we are using less crude, and B) it oxygenates the combustion mixture for a leaner burn. This reduces CO and HC emission, but increased Co2 and NOX. The CAT can take care of the NOX, but the Co2 is left to exit the tail pipe. Ethanol is not added 87 oct to make it 93 oct. To make a different octane grade, they adjust the ration of octane to heptane molecules. Heptane is more volatile then octane, so 87 has more heptane. 93 is less volatile, so it has less heptane.

[bamabonners]

Why does the 6.2 in my Chevy truck run better on 93 than 87? I get better mileage, better power, and smoother running engine on 93.

[Nitrousbird]

Why does the 6.2 in my Chevy truck run better on 93 than 87? I get better mileage, better power, and smoother running engine on 93.

6.2L is a L92, not a 6.0L L96. L92 is tuned for premium fuel, which is why it runs like crap on 87, it is running on the low octane maps and pulling timing.

[nyryan2001]

So you are saying the new 6.2L 450hp motors require 91 or higher?

[Nitrousbird]

So you are saying the new 6.2L 450hp motors require 91 or higher?

Yes, the LS3 also requires 91+ fuel. They aren't all that new anymore - GM released the LS3 in 2008. Malibu used the LS3 in 2010 and it has been in the Axis line for a while as well.

[Night Rider]

It depends on where you are in the country. East Coast premium is 91 or greater on the West Coast I believe it's 89 or greater. I believe the engine manual states premium is 91. But it's been a while since I read that

[MLA]

As noted earlier, names like "Premium" are marketing terms used by the refiner/retailer. Engine manufactures should be making an octane recommendation by stating the R+M/2 octane number and not the marketing terms. This should eliminate any confusion when traveling to different regions where other grades are offered based on other factors like climate, elevation etc. Use the recommended grade, or higher if the recommended grade is not available. Every pump is required to carry the R+M/2 label on it.

[[email protected]]

6.2L is a L92, not a 6.0L L96. L92 is tuned for premium fuel, which is why it runs like crap on 87, it is running on the low octane maps and pulling timing.

What about the LS3? I am almost certain the owners manaul for my 2010 said 89, but then there is some kinda asterick that says 87 will work!! I did talk to Indmar and thye said the 87 will work fine??

Does a base 2010 corvette require 91?? Cause I would think the engine, ECM etc are about the same??? Do you know just what is different from a GM LS3 and a maranized LS3??

MLA is right on. In Sacramento, there is a distrubtion center, where all the gas for the surrounding area is piped to...then your Shell, Texaco, AM/PM, etc all fill up and head to their respective filling station to fill up their storage tanks with gas.... it has been a few years, so I don't remember how and what each truck adds to their tank to make Shell's gas better than their competion, or Exxon, or whoever. it is all the same that goes in your tank!!

thanks.

Edited November 10, 2012 by [email protected]

[Nitrousbird]

^{Does a base 2010 corvette require 91?? Cause I would think the engine, ECM etc are about the same??? Do you know just what is different from a GM LS3 and a maranized LS3??}

^{LS3 is in '08 - '13 Vettes and 6-speed '10+ Camaro SS's. All require 91+ octane. All will run on 87 as well but with reduced performance and mileage, killing any reason to run 87 in them. I doubt Indmar does anything to the motor that would allow it to run less than 91 without reduced performance. They call for 92 in the owners manual for my LS1, though the motor itself has a 93 octane sticker on it.}

[[email protected]]

Thanks Nitrous. I am going to have to look at the manual again. I don't remember any sticker on the engine saying what grade of fuel...there is one for the oil, as it uses/says to use 5W-30. Not sure where I got the idea 87 was ok.

[85 Barefoot]

indmar spec sheet on LS3...says regular:

http://www.indmar.com/Engine/malibu/Monsoon427ss.aspx

[Nitrousbird]

indmar spec sheet on LS3...says regular:

http://www.indmar.co...nsoon427ss.aspx

I already pointed out that Indmar flip-flops on the fuel requirements on their website for the LS3 and LSA depending on who they are listing the motor under. Funny thing is they just updated their site in the last day or two as it is showing different options for Axis now than it did last time I checked.

As for the current website listings, the Indmar category shows the LS3 requiring premium with the Axis/Malibu categories showing it as regular fuel. Yet the Indmar listing shows the LSA as regular with the Axis, Malibu, and Supra listings showing premium. They are all obviously the same motor (just look at the other specs) - it's misprint city, nothing more.

Simply put - their website can't be trusted for this information. Heck, they don't even show all the wakeboats they currently sell motors to (such as MB Sports, Sanger, and Supreme).

Edited November 12, 2012 by Nitrousbird

[[email protected]]

NOt sure who's web site is worse...Malibu or Indmar....both need to some serious work done to make more user friendly, updated, and ACCURATE, etc.

All ya have to do is look at any of Malibu's manuals, they are filled with inconsistencies thruout their manuals: different recommended/std oil, props, etc.

Edited November 12, 2012 by [email protected]

[[email protected]]

Anyone know INDYXC...I recall he works for GM...designing engines...he'd know..maybe??

[nyryan2001]

I got an update on this:

I was on a 24MXZ yesterday with the 6.2L 450hp.....big yellow sticker on the engine says "92 OCTANE FUEL REQUIRED"...