575's..... 89 Octane?
01-15-2007 | 10:27 AM
#1
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From: King george, Virginia/Potomac River
575's..... 89 Octane?
I heard that the computers can be reprogramed so you can run 89 safely in a 575. Long trips it can be a real pain to get 93 sometimes.
True? Anyone?
True? Anyone?
01-15-2007 | 12:12 PM
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From: Tulsa, OK, Grand, Beaver, LOTO
Re: 575's..... 89 Octane?
Book says 91 min for that engine (I had one, still have the book), I can imagine you could detune it (Dustin Whipple or ASM) but if you have 93 in it and spash some 89 you might be fine..... 50 gallons of each gives you 91. You could run a scan tool to verify if your knock sensor is kicking in- I bet Merc has the factory timing setup with some margin....
01-16-2007 | 08:53 AM
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From: Colts Neck,NJ
Re: 575's..... 89 Octane?
Kep the RPM's down and stay out of boost you should be al right. I've put it in my boat in a pinch and never had a problem. But I always top it off with the 93 as soon as I can get it.
