mercury 700 sci Fuel
#1
Gold Member
Gold Member
Thread Starter
mercury 700 sci Fuel
I know mercury states 89.
How many people getting by running 89 octane fuel in stock 700s? I have been running 93 as a precaution but maybe it is a waste of money.
How many people getting by running 89 octane fuel in stock 700s? I have been running 93 as a precaution but maybe it is a waste of money.
#3
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iTrader: (1)
Ours are 91 octane requirement. 93 does seem to soot up the transom. I called Mercury and they said 93 doesn't cause it. I also asked about reflashing ECUs to 89 octane, but they said they hadn't done it in many years and really didn't know if they had the equipment to do it.
#4
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Octane is a measure of a fuel to resist knock. Boosted applications have a higher chance of knocking. I would say running 89 you have a higher chance of inducing knock/detonation and tearing up pistons. I would not recommend.
#8
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I would just 89. I Believe the way that ignition works is it rolls the timing around until it finds a knock and adjust from there. If you're running higher octane it will not find a knock and back up the timing. I'm not 100% positive on this. This is only what I've heard from playing around with the ECM's