Upgrading to a stainless steel Propeller/ Query re millimetrical inclement on OB

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Karnic

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Currently using an aluminium prop 3 x 14 x 19. No issues. Wish to upgrade to a stainless steel one would it have to have same measurements or? If not what dimensions do you recommend?
Also i noticed that outboard was rigged with a few millimeters ( 5/7) of inclement to port side. While smoking a fag and having a cup of tea at garage noticed that OB is very slightly inclined to one side. As boat is jacked i imagined that is the reason,but while examining it carefully and took the measurements i noticed that there is a very slight inclement to one side. As stated not more than 7 mm. Would this issue is a reason for concern? As i bought this new OB from a certified dealer what should i do? Holes on new boat were also done by the man that rigged the OB. What are your Views?
Appreciate your kind help.
 
Its more common to move the engine to the starboard side to counteract prop torque.
Usual theory when changing fron ally to stainless prop is to go down one pitch as the more efficient stainless prop is likely to reduce rpm. That said you need to know what rpm your doing at wot & your engines rated max rpm to decide
 
Once you switch to stainless don’t ground your prop. It’s not as forgiving as alu and can send the shock into the crankcase
 
Beamishken said:
Its more common to move the engine to the starboard side to counteract prop torque.
Usual theory when changing fron ally to stainless prop is to go down one pitch as the more efficient stainless prop is likely to reduce rpm. That said you need to know what rpm your doing at wot & your engines rated max rpm to decide
Click to expand...

5800/5900 RPM at WOT. Manufacturers rated RPM Range is 5000 - 6000 RPM.
 
With you being at the top of the range already. I’d stick to the same pitch.
It’s a black art as you’ll know but often some fast boats can gain rpm going to stainless from ally. Reason being that some of the best of them like the enertia and trophy...laser 2 etc can create so mich more lift on the hull...allowing higher rpm with speed to go.
Be careful though. Some props just suit some boats and some don’t. Is it 3 blade to 3 blade you are going ?
 
These days the old issue with hitting the ground and damaging gearbox and shafts etc...isn’t an issue. Most props these days have sacrificial rubber hubs in them. Only hard splined props from days gone by would have you at risk of damage. Usually at least.
 
Karnic said:
5800/5900 RPM at WOT. Manufacturers rated RPM Range is 5000 - 6000 RPM.
Click to expand...
With those rpm figures I'd stick with the same size stainless your at the upper end of the range which is where you want to be but even switching to stainless is unlikely to drop you out of the recommended range
 
QBhoy said:
With you being at the top of the range already. I’d stick to the same pitch.
It’s a black art as you’ll know but often some fast boats can gain rpm going to stainless from ally. Reason being that some of the best of them like the enertia and trophy...laser 2 etc can create so mich more lift on the hull...allowing higher rpm with speed to go.
Be careful though. Some props just suit some boats and some don’t. Is it 3 blade to 3 blade you are going ?
Click to expand...

Yes 3 blade
 
MapisM said:
So, why change the prop?
Sounds like you are trying to solve a problem that doesn't exist, imho.
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Generaly you will see a performance improvement from ally to stainless either via higher top speed or improved economy.
Everytime I've switched from ally to stainless I've seen a performance gain
 
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