Should I Change Bravo Three Gear Ratio

[loutax]

I recently changed the motor in my Formula 252SS from a Mercruiser 7.2(454) to a 383 Stroker. Similar horsepower, less torque.
When I went to water test the boat No Pickup at all.

I changed the props from 26 pitch to 22 pitch which improved holeshot significantly.

Problem is that wide open throttle rpm is still only 4650. Spec on engine is 4800-5200RPM.

I am running a Bravo 3 with a 1.81:1 gear ratio.

Should I change the gear ratio on the Bravo Three to a 2.0:1 or a 2.2:1 or should I go down to the last prop available at 20 pitch. Is there any difference between those two solutions. Props are obviously cheaper to change.
Top speed is not as important to me as holeshot.

 

[Maclin]

Re: Should I Change Bravo Three Gear Ratio

Fom the hands on mechanical physics I have learned in my career playing with power sports toys......

Less torque available = higher ratio needed

That is true in cars, bikes, sleds, boats, etc.


I'm just sayin'


There will be a definite advantage for you to change out the ratio. If you do go to the next one up drive ratio closer to 2.0 to 1 then your prop choices are back to "normal", meaning that now a 24-26 will work the same as the 20-21 works now and you still have some room to move up or down for fine tuning.

Up to you to determine if the benefits balance out the costs.