Gas Octane Reating

[rjehmiller]

I have a 1986 40 HP evinrude. I was wondering if I should be OK using 92 octane gas in my gas oil mix?
If I remember correctly my manual said soemthing about 67 octane gas ( I have never seen such a rating at the puimp)
Please advise.

 

[Pony]

Re: Gas Octane Reating

You should be using 87 octane and TCW-III rated oil. 92 octane wont improve your performance, and will probably hinder it because it wont combust the same way as the 87...............so save your $ and get the low grade.

 

[rjehmiller]

Re: Gas Octane Reating

It should be ok to run through 6 gallons of gas and should not heart the engine correct?

 

[wilde1j]

Re: Gas Octane Reating

You're fine ... just don't waste your money.

 

[Rancherlee]

Re: Gas Octane Reating

I think one reason he might have tried 91 octane (being from minnesota) is that in our state ALOT of gas stations have what is called "Non-oxy" gas in 91-92 octane which is 100% dyno gas instead of a 10% ethonal mix like 87 and 89 are. this non oxy gas is listed for OFF-ROAD/collector cars only but I run it all the time in my vehicals and the difference in fuel mileage more than makes up for the added cost over 87 octane E10. cost me about 15 cents more a gallon (5% more over 87 e10) BUT I get 10-15% better fuel economy in my 02' Mountaineer (22-23mpg highway instead of 19-20) and the same goes for my Lincoln Mark VIII (22 mpg around town to work and only 19mpg with the E10)