PROP FOR 9.8 TOHATSU

[rocket rich]

WHAT IS THE DIFFERENCE BETWEEN 7.5 AND 8 WHEN SIZING A REPLACEMENT PROP

 

[Sea Rider]

In light boating applications can mean as much as + 250 revs at wot with a 7.5 pitch and -250 wot revs with an 8 pitch at wot. You should always test any factory delivered prop with an induction tach that way will know if current prop will achieve max or near max wot rpm. Can go from there maximizing for - or + size pitch to suit your boating needs and applications.

When achieving near max wot numbers, that's you alone and lightly loaded combo on flat calm no wind water cond ? An 8 will lower a bit max wot rpm and with a 7 will gain extra wot rpm theoretically in that range.

Happy Boating

 

[rocket rich]

thanks Sea Rider, so with prop that came on the motor is really just a maybe 50 rpm from max which is 6000 .. I can get 5940 wot rpm's . I don't want any more ..other wise the Rev Limiter take over. So I think the 8 is best for my boat. I'm having a problem with the boat as I'm slowly getting weaker, ?? Oh well just another day in the golden years.

 

[Sea Rider]

RR,

Stay with 8 pitch, you're already at the max wot range, -50 RPM is nothing.

Happy Boating