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Old 08-12-2014, 04:46 PM
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What if your engine requires 91/93 but only 87 octane at the marina?

I bet this has been asked before. What if your engine requires 93/91 octane but the marina on the lake (Lake Powell) only has 87 octane. We fill the boat up with 91 before we put it on the lake but when you are 40 miles down the lake and need gas... Can you point me to any articles/website about this?
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Last edited by Cmpdman; 08-12-2014 at 05:10 PM.
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  #2  
Old 08-12-2014, 05:00 PM
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Rossterman Rossterman is offline
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Most modern engines (like yours) employ knock sensors which reduce the timing advance (and results in HP reduction) if detonation is encountered to prevent engine damage. So, slightly less power is about the only consequence that occurs.
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Old 08-12-2014, 07:22 PM
ncsucarjock88 ncsucarjock88 is offline
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And increased fuel consumption due to the retarded timing. But yes... no harm on the newer engines... they will adapt.
Can't believe they don't have 93. I run 93 in everything just for the added detergents...
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Old 08-12-2014, 07:44 PM
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Quote:
Originally Posted by Cmpdman View Post
I bet this has been asked before. What if your engine requires 93/91 octane but the marina on the lake (Lake Powell) only has 87 octane. We fill the boat up with 91 before we put it on the lake but when you are 40 miles down the lake and need gas... Can you point me to any articles/website about this?
Does the gas have ethanol? If not, you can add some denatured alcohol and that will raise the octane rating, but you'd need to do some calculations to find the amount needed to raise it to 93. Since it's hot and dry, moisture in the gas should be no problem.
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Old 08-12-2014, 08:01 PM
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Quote:
Originally Posted by JimN View Post
Does the gas have ethanol? If not, you can add some denatured alcohol and that will raise the octane rating, but you'd need to do some calculations to find the amount needed to raise it to 93. Since it's hot and dry, moisture in the gas should be no problem.
I don't remember is there was ethanol in their gas. I do know they sell octane booster for about $12 (wow!) a bottle.
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Old 08-12-2014, 08:28 PM
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I don't remember is there was ethanol in their gas. I do know they sell octane booster for about $12 (wow!) a bottle.
Look at the ingredients- might as well use denatured.
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Old 08-15-2014, 09:18 AM
ncsucarjock88 ncsucarjock88 is offline
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Right. You can go to lowes and pick up the ingredients for octane booster. Tolulene, xylene, alcohol, all of it at a fraction of what it costs in the little bottles...

Just be careful... it will strip wax, stickers, paint, etc...
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Old 08-15-2014, 11:30 AM
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store bought octane booster raise the octane very little. If it says two points it really means two tenths.
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Old 08-16-2014, 02:44 PM
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What marina are you at??
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  #10  
Old 08-16-2014, 08:05 PM
uplander uplander is offline
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run 87 you will be fine, I had the same issue on vacation. Ran 87 all week with no issues.
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