Posts: 32935
Location: Rhinelander, Wisconsin | What rpm are they getting with a 25 tempest---Depends on the load and what the height of the motor is. Optimally, the RPM's reached will be in the lower end of the acceptable RPM range with this wheel. The higher the motor mount, the higher RPM's will be available...to a point. Once that point is passed, the prop loses bite and performance is degraded.
What is the right load ?---light to medium load, distributed forward more than rear.
What are the conditions? ---Medium chop so the boat can easily get some air under it.
What is optimum height?(raised up all the way on the transom or running a jackplate)---I don't remember the measurement from the running bottom to the cavitation plate, but the motor was about two holes up if I remember correctly.
Dont forget overpropping an outboard will slowly kill it --If the blade runs in the acceptable RPM range, it will be fine. If not, then down a pitch...
Try the 21 pitch if the 23 is too much blade. if the 23 is perfect, there it is. Try the 25 if the 23 is right at the line for max RPM on your particular hull.
I'll take a look at the May Anglers Insight Marketing tournament and this weekend's upcoming MWC on Oahe, I'll be shooting about 20 Rangers or more at those two and quite a few will have Merc 250 XS power. I'll also ask Jay at the tech trailer, he'll know the perfect prop for each condition.
As I said, the Rev 4 takes more to spin it, and will require a drop in pitch or even two or more from a three blade, especially the Tempest Plus. |
