[CaptMick]

Seloc manual I have sucks but states 90 to 110 PSI. It says that is for a 200 - 250 from years 2001 to 2005 but it does not say specifically for an optimax of that size. That is why the manual sucks.

There is an additional note that says ,"MOST Mercury motors 90-120 PSI is the lower limit for acceptable compression (at least for mid range and larger motors.)"