big difference in stainless and alum props?

[BigBoatinOkie]

I have a 20" stainless prop on my Wellcraft 18' bowrider 228 hp merc I/O. I want to go to an 18'' prop for more pulling power. I know that there will be a loss in top speed which is fine, but if i go to an aluminum prop will i lose even more speed or will I not benefit as much from the pitch change. I have heard some say that stainless props offer a much more performance, and some say it's not that big of a difference. I don't want to sacrifice too much performance, but i also would rather not pay 400 bucks if it's not worth it. I boat on freshwater lakes and rarely encounter rocks and logs, so not worried about hitting stuff. I havn't been boating long, but I have only had SS props and this will be my first prop purchase. I run 50 mph with a 20", could I run an aluminum 18" and stay around 45 mph?

 

[rs1lollie]

Re: big difference in stainless and alum props?

Look into getting a 4 blade prop in ss or aluminum , they get better hole shot and plane faster and maintain plane at lower speed, and maybe only lose 1-3 mph at WOT

 

[BigBoatinOkie]

Re: big difference in stainless and alum props?

I found a Michigan Wheel Apollo XHS Stainless 4 blade 14 3/8 x 18" for $224. Or a Michigan Wheel Vortex aluminum 4 blade 14 1/2 x 18" for $84. Do those sound like a good choices?

Your supposed to go down a pitch with a 4 blade prop right? So if my thinking is correct (which is rare), it should give me the holeshot like an 18" three blade and the top speed of a 19" three blade. Is that correct? Or am I an idiot? There are to many freaking options.

 

[rs1lollie]

Re: big difference in stainless and alum props?

what is the WOT rpm rating for your engine, what is actual WOT rpm and speed with 20" prop?

 

[BigBoatinOkie]

Re: big difference in stainless and alum props?

Max rpm at WOT is 4600 rpm for my engine and I'm only running 4000 rpm at 50 mph. So I need to drop to the 18" to get my rpms in the right range.

 

[rs1lollie]

Re: big difference in stainless and alum props?

Yes that sounds good, But I would look into getting a Solas Rubex or altma prop in that size or a mercury prop. I found that MW has a different cup on their props that I did not like. You can also try to ask hwsiii in this form he has helped a lot of people with similar problems and they hav been very happy with the out come.

 

[BigBoatinOkie]

Re: big difference in stainless and alum props?

Yeah I talked to hwsiii and he recommended the 18" pitch. Looks like Solas props are all odd numbered pitches. I saw those MW props for real cheap, that's why I asked. I'll ask him what specific props he recommends. I'm trying to get the best bang for the buck.

 

[rs1lollie]

Re: big difference in stainless and alum props?

I bought a brand new prop from this guy on ebay, great price and fast shipping,
here is the item # for the prop you are looking for. just enter this # in the search part of ebay. Item number: 380152180862

 

[BigBoatinOkie]

Re: big difference in stainless and alum props?

this flo-torq II hub system is compatible with '84 alpha 1 gen 1 outdrives?

 

[rs1lollie]

Re: big difference in stainless and alum props?

I have a 1990 alpha 1 out drive and it works with mine, Fits the following applications,

Mercury and Marinier Outboards applications.
2 cycle 60 hp Bigfoot ? Fourstroke 40 through 60 hp Bigfoot
70 through 250 hp

Force Outboards?
90 through 120 hp Dual Exhaust 1995 and newer

Mercury MerCruiser?
Alpha and Alpha One
Bravo One? (less than 400 hp)

The service manual for alpha 1 out drives is 1983-1990.
http://www.boatfix.com/merc/Servmanl/6/6covr3.pdf

 

[hwsiii]

Re: big difference in stainless and alum props?

Okie, just get the 17" pitch in the Solas Rubex, this will not lose more than 2 MPH top speed and bring your RPM up to about maximum RPM.

IBOATS
Price: $126.98
You Save: $30.97
Compare: $157.95
Discount: 19.7% Off
Add RUBEX 4 Aluminum Propeller Prop: 9513-145-17 Hub: RBX-102 To Your Cart

Propeller Specifications:
SKUrop #9513-145-17Hub #RBX-102
Manufacturer: Solas
Brand: RUBEX 4
Material: Aluminum
Diameter: 14 - 1/2?
Pitch: 17?
Blades: 4
Rotation: Standard (Clockwise)
Usually Ships Within: 1 Business D


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[BigBoatinOkie]

Re: big difference in stainless and alum props?

you saying i can run a 17" solas rubex and still achieve 48 mph at 4600 rpm? hwsiii. i bet you're getting frustrated with me. i promise i'm not as dumb as i seem.

 

[BigBoatinOkie]

Re: big difference in stainless and alum props?

But, if I'm gonna go all the way to a 17" pitch, shouldn't I just go with a 3 blade. A 17" should rip the arms off anyone hangin on to the rope, and i should retain a few mph on the top end.

 

[hwsiii]

Re: big difference in stainless and alum props?

Then just try a 17" 3 blade.


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