Type of Fuel - I’m Confused

[Pathfinder2200v]

After reading the FAQ, I’m confused with what type gasoline I should be running in my 2020 Mercury Fourstroke???

Since 2005’ish, I’ve always run Rec-90 with different types of fuel additives over the years. When I got this new Merc, I didn’t think twice about continuing to run Rec-90 w/ Don’s cocktail. After re-reading the fuel thread in the FAQ, it appears to suggest I should be running plain old 87 Octane gasoline for best performance…HELP!!


FUEL:
-All models- MAXIMUM ETHANOL CONTENT: 10%. Ethanol content may adversly affect engine performance.
-See "Mercury's View of Ethanol" on Sherm's board at: Mercurys take on Ethanol blended fuel

OCTANE:

-Standard 4-stroke Engine Models (Including V6/V8 Fourstrokes): 87 Octane
-Verado PRO Models: 87 Octane Minimum (improved performance with 91+ Octane)
-Verado 350 (new production model)- 91+ Recommended (89 minimum)
-Verado 350 SCI/Racing: 92 or above recommended
-Verado 400R: 92 or above recommended

[fishnfireman]

After reading the FAQ, I’m confused with what type gasoline I should be running in my 2020 Mercury Fourstroke???

Since 2005’ish, I’ve always run Rec-90 with different types of fuel additives over the years. When I got this new Merc, I didn’t think twice about continuing to run Rec-90 w/ Don’s cocktail. After re-reading the fuel thread in the FAQ, it appears to suggest I should be running plain old 87 Octane gasoline for best performance…HELP!!


FUEL:
-All models- MAXIMUM ETHANOL CONTENT: 10%. Ethanol content may adversly affect engine performance.
-See "Mercury's View of Ethanol" on Sherm's board at: Mercurys take on Ethanol blended fuel

OCTANE:

-Standard 4-stroke Engine Models (Including V6/V8 Fourstrokes): 87 Octane
-Verado PRO Models: 87 Octane Minimum (improved performance with 91+ Octane)
-Verado 350 (new production model)- 91+ Recommended (89 minimum)
-Verado 350 SCI/Racing: 92 or above recommended
-Verado 400R: 92 or above recommended

I bet the paperwork that came with your new motor says the same thing !

[Pathfinder2200v]

I bet the paperwork that came with your new motor says the same thing !

Yep…reads very similar: “A posted pump octane rating of 87, minimum, for most models. Premium gasoline 91 octane is also acceptable for most models”

Does this mean Rec-90 (or Rec-87) is no longer recommended for outboards, as it has been the preferred since the early 2000’s??

What gasoline do you use?

PS. Hate to spend time on what I thought was a no-brainer when it came to what type of fuel for outboards…as I’ve only run Rec-90 in my outboards, so the FAQ here and the Mercury Manual have me perplexed.

Thanks.

[gehol]

Maybe just follow what Mercury says for your motor. I think it will say MINIMUM 87 octane and 10% maximum ethanol. Does Rec 90 meet this spec? If so you may use it but you are likely wasting money on the Rec 90.

[Lowerider58]

Today’s motors are way more technical than what they were 20 years ago. There are multiple sensors sending information to the ECM to fine tune fuel mixtures and spark timing. The motors being built today are designed to run on 87 octane.

[SilverFox579]

Standard 4-stroke Engine Models (Including V6/V8 Fourstrokes): 87 Octane

Unlike your owner's manual, the FAQ info is continually updated with most current information provided by Mercury.

Many people misread the octane statement, there are several locations in the US that sell fuel with an octane rating LESS than 87. The statement in your owner's manual isn't meant to imply 87 is the "minimum" acceptable octane, it means NO LESS than 87. You can run 89, 90, 91 or higher but you won't gain anything on an engine tuned for peak HP and performance using 87 octane except a lighter wallet at the pump.

[fishnfireman]

Unlike your owner's manual, the FAQ info is continually updated with most current information provided by Mercury.

Many people misread the octane statement, there are several locations in the US that sell fuel with an octane rating LESS than 87. The statement in your owner's manual isn't meant to imply 87 is the "minimum" acceptable octane, it means NO LESS than 87. You can run 89, 90, 91 or higher but you won't gain anything on an engine tuned for peak HP and performance using 87 octane except a lighter wallet at the pump.

Due to our elevation the Panhandle of Texas including Amarillo is one. The low grade is 86 and the high is 90. So I have to buy the higher priced mid grade(88) to meet the minimum of 87.
I've always wondered if 86 would be ok if ran at this elevation.

[gehol]

LOL, Silverfox, what is the difference in minimum octane and no less than 87?

[1Holeshot]

LOL, Silverfox, what is the difference in minimum octane and no less than 87?

Valid question even if the answer is obvious ( hence the LOL ).

[EuropeanAM]

LOL, Silverfox, what is the difference in minimum octane and no less than 87?

The person making the statment, quite simply.

Pathfinder- follow the suggestions in the FAQ post for best results (especially long-term). If you stick with the criteria listed, IN THE ORDER LISTED, you should be in good shape.

[Pathfinder2200v]

The person making the statment, quite simply.

Pathfinder- follow the suggestions in the FAQ post for best results (especially long-term). If you stick with the criteria listed, IN THE ORDER LISTED, you should be in good shape.

As always Don: thank you Sir

[SilverFox579]

LOL, Silverfox, what is the difference in minimum octane and no less than 87?

To me none, to others, it means "if 87 is minimum, then anything higher is better" and it's not.