250HP HO fuel question

[Chad Anderson]

In my area I can choose either 91 octane 100% gas or 93 octane with 10% ethanol. Same price.
Which would be better in the HO engine for performance?

 

[Rtimleck]

I say avoid ethanol if you have the choice.

 

[ALAN MANN SR.]

I use 93 pump gas 10% ethanol with Sta-Bil 360 every tank full. Keep the tank full and have had no problems. Have tried there ethanol free 91 and have had all kind of problems. Tried octane boost in 91 with worse results. So for me it has been 93 pump gas. 177 hrs. on a 2015 Scarab 165 250 hp. and going strong.

 

[Chad Anderson]

Well i've tried a tank of both and see no difference in performance. 8100rpm / 45mph with a light load and cool temps. Boat runs strong with either.
Guess I'll go ethanol free 91 just to eliminate the potential headaches that ethanol fuel can bring.

 

[swatski]

Well i've tried a tank of both and see no difference in performance. 8100rpm / 45mph with a light load and cool temps. Boat runs strong with either.
Guess I'll go ethanol free 91 just to eliminate the potential headaches that ethanol fuel can bring.

I would do the same if I had that option. The non-ethanol fuel being 91 is unlikely to help performance (knock sensors probably won't sense any knocks with 91 - just as 93), should extend your range though.

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