What Octane fuel do you put in your boat?

[Horton]

What Octane fuel do you put in your boat?

[RichardDoane]

The Ski Brendella runs best on regular.

[Horton]

I'm really asking about newer boats...

[RichardDoane]

@Horton I ran all my MC promos on 87, that was 2010 thru 2014 boats

[KRoundy]

Only 91 or higher goes in my 200.

[thager]

I use what the manual says for minimum octane and I stay away from alcohol percentages greater than those recommended. I use no alcohol fuel when I can.

 

[Jody_Seal]

You missed a choice! Ethanol free fuel.

I try and run at least 89 ethanol free.

[MISkier]

If I’m at a gas station without recreational fuel (no ethanol), I use 89 octane, which is what is listed in the manual. But, I really try to get the rec gas, which is usually 91 octane. I think I was able to run all rec gas last year. There is a station that sells it about 5 miles from my house.

 

Side note: I only use rec gas in my mower, generator, and all other small engine equipment. The ethanol is terrible for those engines.

[A_B]

@MISkier i do the same in all my yard toys. I think the car and boat engines are all equipped to handle the E blended gas better. Although it makes perfect sense to do so. I just start running additive for winter as we get close to the end of the season so I know it’s through the system.

[skiinxs]

6.2 D.I. engines run fine on 87 with no damage, but retard timing advance resulting in lower power output. It takes a bit of running on 93 or a battery disconnect to go back to normal. I always run 93. Wish I could get alcohol free gas, but if isn't available in my area.

[rfa]

Always 93. Currently on 2013 5.7 ILMOR, before on 2008 INDMAR Monsoon. Wayback, on 2000 PCM GT40

[jhughes]

The 6.2 and 5.3 DI motors call for premium, I believe they run something like 11:1 compression which is the same compression as the S62 in my M5. So my 200 with the 5.3DI gets premium.

 

In my GT40 I'd run 87 all day but up by the lake the only carry ethanol-free in premium so it gets premium too.

[ALPJr]

Our newer boat was a ‘92 MC190

[aupatking]

I’m not all that concerned about octane, just alcohol/ethanol free. Most of what I find as no-alcohol “marine gas” is either 88 or 89. I suppose if there was no “marine gas” option, I’d go 91+

[MarkTimm]

A handful of years ago I had a 500 gallon tank of non ethanol premium. My boat at the time was an SN with the GT40. When I switched to regular pump gas with ethanol, there was a noticeable difference in engine performance.

[Alberto Soares]

6.0 200 about 1500 hrs - regular 87 with 27% ethanol (only gas available here) - so far, so good