decisions decisions which to choose

Hey guys,
Looking to buy a new prop. I don't NEED a new one, but I'm a bit of a boy scout and would like to carry a spare. So I figure if I'm gonna get a new one is add a little extra performance while I'm at it.
The boat is a 85 four winns santara fisherman 217
omc stringer 800 (not sure of th he gear ratio)
3.8 l motor
Don't remember the weight
wot is 4600 ish
GPS speed 36

Bennett tabs

I'm pretty happy with her overall. Don't need more speed. She gets out of the hole just fine. If extra people are on board the tabs help out.
The prop it's original 14.25x19 stainless. It was just gone over last year so it's in great shape.

I will be going to a 4 blade solas aluminum. I'm choosing this because I boat/fish lake Erie. Channel water can be low at times and tough water is normal. 4 blade should help with rough water aluminum should help with low water prop strikes.

So 4 blade 14.25x17 or 14.25x19

I'm leaning toward 17
With the UPS and downs of rpms this should keep me in the same rpm range

I normally cruise about 3000 rpms at 22mph ish
I'd like to drop the rpms a bit and keep that same speed of possible 4 blade should help that.


Any thought or opinions would be great
Thanks in advance

Re: decisions decisions which to choose

If you go to a 17 your rpm will be higher at 22 mph.The lower pitch and 4 blade should make it easier to maintain plane at reduced throttle.Less fiddling.
Boat will be peppier but top end slower. Changing material, probably brand and number of blades really
makes it difficult to predict.I like a 1" pitch reduction but do wonder about the 4 blade lowering the rpm too much.
Then there is the change to al.I think that motor will be happier at a lower rpm if its within the rpm range.
If you can find it a 18 I think it will get to 22 with less throttle than the 17.

Re: decisions decisions which to choose

I keep going over the same things I'm my head also. Everything being equal changing to aluminum should bring a reduction in rpm. Changing to 4 blade should reduce the rpms also. Dropping pitch should negate one of the drops in rpm. Generally speaking I don't like to make this many changes at once.however I'm not buying 4 props I'm gonna make my best guess and live with it. Fortunately I'm pretty close to good right now