Mercury 2 stroke 90hp ECU "flash"

[BassmanRudy]

So I have talked to Simons over in California and they said if I send them my ECU they can flash it to 120hp. Its been a while (so don't remember all the particulars) but I know I'll need to set a new "rev limit" which is most likely going to be 61-6300 now instead of 5800. They told me I wouldn't need to change spark plugs or my prop which would be nice. I might play with a new prop anyways to see what happens. Currently running a 19P Powertech.

My reason(s) for wanting to try the flash-
Better top end speed so I can increase my fishing options
Cheaper than buying a 115hp motor
Better fuel economy by not maxing out my RPMs to achieve same speed as before.

Anyone flashed their ECU before on a smaller motor? Any cautions/advice?!

Thanks in advance! :-)


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[Oldfart9999]

I know Mercury as well as others use the same powerhead for different HP levels but I would be leery of doing it with just a puter flash, there is usually differences in exhaust and other components. What happens if in the long run it ruins your ecm?
Rodney

[BassmanRudy]

Yeah I need to ask about "coverage" if in say 6 months the motor blows.

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[Mike Cork]

Like Oldfart pointed out there is usually some things that need to be done to accommodate a hotter motor, by increasing HP you are changing many things in the fuel delivery system and exhaust system. However, those things may already be there in your motor and Merc just uses different ECM's

[BassmanRudy]

I hope so Mike. They (at Simon's) didn't give me any real concerns but its been a while since I talked to them. Would love to get it to 135(max for the boat) but don't know if that's possible

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