Adjusting high speed jet

[mk55]

I adjusted my high speed jets and low on the boat in the water with a test prop. I set high speed to just where it started to slow the motor down (lean) and back to full rmp + and extra 1/8 turn. with synthetic oil at 50 to one. Now when i follow the advice you gave me to change to 32 to one syntehtic, will the high speed jets be ok where they are with the extra oil.
Dave.

[Mark75H]

You will not need to make any change. Convert the ratios to percentages and note the very small difference.

I have switched between 40:1 and 18:1 (more than twice as much oil) without making a change.

[2us70]

Those old motors did not seem to mind some extra oil in the mix. They had a low octane requirement so the extra oil didn't cause detonation and if you didn't idle much plug fouling was not too bad. I used to run at least double the oil in my old Merc 500s with no problems.I always figured that this helped the motors live at 6k+ rpms for many hours. Those motors just need a good hot mag,good timing and jetting.