solas rubex 4 blade

[MBAKER]

How predictable would a change from powertech aluminum 3 blade 19P prop to Solas aluminum 4 blade 19P prop be? From what I read I expect to lose maybe 100 rpms, but im a little past the top rpm anway so I can live with that, I just dont want to lose several hundred. I didnt know how much difference there was in blades and how the effective pitch the boat sees varies between the 2 brands.

 

[steelespike]

Re: solas rubex 4 blade

The Solas props do a have a reputation for predictable results.
A 19" prop should perform like a 19" prop.Going to a 4 blade will usually lose about 100-200 rpm.
" Usually" the 4 blade will have a smaller diameter.
To be able to try to predict your results we would need your present performance. Wot rpm and gps speed.
This will help tell if your tach is accurate before making any changes.
I can say your "probably" going to lose some top end,hole shot "should" improve,"should" stay on plane easier
at reduced throttle,"could" feel smoother,and "may" respond better around the dock.

 

[jestor68]

Re: solas rubex 4 blade

You will drop 100-200 rpm. If that's how much over your max recommended rpm you are now, things will be :joyous:

 

[MBAKER]

Re: solas rubex 4 blade

Currently with an average to heavy load I will get about 4900 untrimmed, dont have a GPS speed. I say untrimmed because the powertech prop seems to carry the boat higher, you cant really trim out much or it starts to blow out. Plus the rev limiter kicks in at 4950 so Im just guessing it might gain another 100 or so if trimmed out. I feel the tach is accurate because of the rev limiter, and the rpm indicated when it kicks in.

I am not concerned with WOT speed, most of what we do is cruising and pulling tubes/skier etc. Thats why I went with the 19 currently even thought it would pull a 21 in most cases. The problem Im having is I'm getting cavitation with the 19, so I want to try and go to a 4 blade for more grip and low speed power. I just didnt know switching brands how they would act, as Ive read some brands act stronger on pitch than others. I would just like to hook up better at low speed. Not necessarily kill off many rpms because I would rather not lug it through the low speed and midrange.