Mercury 280 ROS Fuel

[yamahasrx26]

Quick question what are guys running for fuel in the 280 ROS consumer model? What do you feel runs best in the 280 thanks:thumbsup:

[mach351]

Stock 280’s have about 145-155psi....I wouldn’t run anything less than a 93 octane. Preferably non ethanol and I’d probably splash it with some aces.

[kelvin523]

(50/50) - (110 / Sunoco 93) worked well for us with Amsoil . 280 ros is my 2nd favorite motor so far; requires prescriptive maintenance. Also prefer the heavy rods, jmo\

[yamahasrx26]

Anyone know where I can buy it at the pump non-ethanol here in upstate NY...........if not where can I buy it and have it delivered.......which fuel will mix with the mercury racing oil and could i 50/50 it with non-ethanol 90 octane? thanks

[yamahasrx26]

maybe thing to do is run non-ethanol 90 octane and hit it with some aces???.........aces 1oz to 6 gal of gas anyone else using this? should bring it up to over 93 octane anyway?? how expensive is aces and who is a distributor (where can i buy it) thanks

[kelvin523]

I'm happy to give the facts as we ran, not interested in others feedback. Ethanol; didn't factor it in as we ran 100gl+, only important for us was not to leave gas in the tanks. Again, liked the Amzoil red stuff 50/1 - 50-50 (110-93). Enjoy those ROS motors, imo\ pop the heads often; look for egging, again jmo\.

[patchesII]

I'd stick with 93 octane and 32:1 oil

[yamahasrx26]

I'd stick with 93 octane and 32:1 oil


I can only get 93 octane with ethanol where I live..........have seen what it does to 2-strokes in sleds, dirtbikes etc........I dont like phase seperation to say the least that's why i was thinking of trying aces with 90.9999999 non-ethanol fuel here anyone run aces?????????

[mach351]

Charlie on here (mrcrsr) sells Aces.

One gallon of 110 to every two gallons of 90 will put you in a good spot too if you can get some.

[Markus]

I can only get 93 octane with ethanol where I live..........have seen what it does to 2-strokes in sleds, dirtbikes etc........I dont like phase seperation to say the least that's why i was thinking of trying aces with 90.9999999 non-ethanol fuel here anyone run aces?????????

ACES will not help. It does not increase the octane of the fuel. Just what the sellers call "octane effect". It does not show any effect on an octane test engine according to the sellers.

In a 4-stroke, it supposedly helps with upper cylinder lubrication, as the oiling system supposedly is deficient in all 4-strokes. (You may or may not choose to believe that statement)

On a 2-stroke, you have oil in the fuel already, so that "argument" falls away.

There was a guy on here who believed in that stuff and burnt the pistons in a pair of 2.5 280s some years ago...