91 octane in new V8 ?

[fishnfireman]

I have about 15 gallons of 91 in my tank.. Should it be ok to top off with 87 and run in a 250R that has 45 hours on it ?
(36) gallon tank. I figure it would be alright what do ya'll think ?

[white gambler]

Yep, I've ran high test in mine every time. The places around here only carry non ethanol in high test and I'd rather run it than 87 with ethanol.

[TB21]

You are promoting carbon build up and making less power by running higher octane than 87 in a 250R.

Yep, I've ran high test in mine every time. The places around here only carry non ethanol in high test and I'd rather run it than 87 with ethanol.

[tritontr21]

I have about 15 gallons of 91 in my tank.. Should it be ok to top off with 87 and run in a 250R that has 45 hours on it ?
(36) gallon tank. I figure it would be alright what do ya'll think ?

It will be fine in my opinion. I would run 87 from here forward.

[white gambler]

You guys don't mind the ethanol? I always thought a point or two higher in octane vs.having ethanol fuel sitting in the tank was the lesser of the two evils. I realize the newer stuff, fuel lines, etc, are designed to better handle ethanol than from years ago. I realize also there are fuel treatments that help. Sometimes my boat sits in the shop for several weeks at a time. I figure high test may lose a point or two of octane and no big deal since it started out higher. I'm all ears though for you all's input. I'm not adverse to change.

[River Rocket]

I have the same problem we only have non-ethanol gas in 91 octane and above. For the reasons Tim mentions I was told to run 87 not 91. So now I don't fill my tank. I just keep 10-15 gallons in it. Since I'm always testing props the gas doesn't sit around long....

I treat every tank with Ethanol treatment.

I had 91 in it from the 300XS. I ran that out during break in.

[tritontr21]

You guys don't mind the ethanol? I always thought a point or two higher in octane vs.having ethanol fuel sitting in the tank was the lesser of the two evils. I realize the newer stuff, fuel lines, etc, are designed to better handle ethanol than from years ago. I realize also there are fuel treatments that help. Sometimes my boat sits in the shop for several weeks at a time. I figure high test may lose a point or two of octane and no big deal since it started out higher. I'm all ears though for you all's input. I'm not adverse to change.

I guess I should have clarified that I run 87 non ethanol. On my old 250 Sport I ran 1 tank of 91 or 92 non-ethanol at Clifton and discovered my Opti didn't like the higher octane. Cost me over 3 mph on day 2 of the rally!

[white gambler]

Interesting, would've never guessed it could be a 3mph swing.

[River Rocket]

No buddy liked the gas in Clifton. Killed my boat as well.

[xb03fs]

Same

[tritontr21]

Maybe it wasn't all the octane but I am convinced that was it. Burned through the rest and put 87 non ethanol back in when I got back to Texas and boat picked speed right back up!

[gehol]

This is so funny. It is amazing how these old wives just keep hanging on.

[white gambler]

This is so funny. It is amazing how these old wives just keep hanging on.

What does this mean?

[gehol]

Sent PM to white gambler.

[TB21]

Huh?

This is so funny. It is amazing how these old wives just keep hanging on.

[fishnfireman]

This is so funny. It is amazing how these old wives just keep hanging on.

care to expound on which wife ?

[gehol]

care to expound on which wife ?

You have a PM