Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel prop

Hi everyone,

I have a 20 ft Four Winns Horizon H200 powered by a 5.0 GXi Volvo Penta SX sterndrive.

Current prop is an OEM Volvo Penta aluminum 14.3" x 21", top speed 52 mph, WOT 4800 rpm, 200 rpm below max engine speed given by manufacturer (5000 rpm).

I want to switch to a stainless steel prop and after some readings I found out that the SS Stiletto Advantage could be a good choice. This prop also seems to have more cup.

I am considering the SS Stiletto 14.25" x 19" (2" pitch decrease) given the extended cup and the current 200 rpm below max engine speed.

Am I right or should I stay with the same pitch (Stiletto 14.25" x 21")?

Thanks for your replies.

Re: Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel

Ayuh,... I'd think the Same pitch would work out well for ya....

I'm guessin' a 19" might be too small...

Re: Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel

Captain Man said:

Hi everyone,

I have a 20 ft Four Winns Horizon H200 powered by a 5.0 GXi Volvo Penta SX sterndrive.

Current prop is an OEM Volvo Penta aluminum 14.3" x 21", top speed 52 mph, WOT 4800 rpm, 200 rpm below max engine speed given by manufacturer (5000 rpm).

I want to switch to a stainless steel prop and after some readings I found out that the SS Stiletto Advantage could be a good choice. This prop also seems to have more cup.

I am considering the SS Stiletto 14.25" x 19" (2" pitch decrease) given the extended cup and the current 200 rpm below max engine speed.

Am I right or should I stay with the same pitch (Stiletto 14.25" x 21")?

Thanks for your replies.

Click to expand...

Welcome aboard!

I think it's gonna be close... the SS should give a better dig into the water, thus reducing slip and rpm. However, we may not be talking about enough rpm to constitute a 2" reduction. With your numbers being so good already, what is it you want to improve upon? Maybe a better hole shot and 2-3 mph increase?

Did you give data when near empty or loaded down? Then answer, if you usually run empty or loaded down. Also, if you like water-sports (pulling skiers or tubes).

Good luck and let us know which way you go.

Re: Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel

The goal is to improve overall propeller efficiency, speed and also fuel consumption.

The given data were near empty (2 persons), we also run more weighted and practice water sports (ski, wakeboard and tube).

In the meantime I have downloaded a propeller calculator software at Castle Marine (http://www.castlemarine.co.uk/pitch.htm) and conducted some simulations.

Parameters entered:
- Hull Type: Planning High Speed Runabout
- Length at Water Line: 19.8 feet
- Displacement: 4000 lbs (boat & engine 3100 lbs, max capacity 1400 lbs)
- Single Engine/Inboard Outdrive
- BHP: 270
- Max RPM: 5000
- Gear Box Ratio: 1.6

The software returned a theoretical pitch of 19.1" and a diameter of 15.5".
When changing down the displacement parameter to 3400 lbs the calculated pitch increased to 20.5" for the same diameter.

I think you are right it's gonna be close, running empty or loaded down seems to have a significant impact.

My assumption is that if the figures are correct and if the boat is used with an average 4000 lbs displacement, I should lean toward a 19" pitch prop.

However the SS Stiletto 19" has a smaller diameter (14.25") than the theoretical diameter returned by the program (15.5"). Do you think I should also consider other SS props with a larger diameter such as the OEM Volvo 14.75" x 19" or the Quicksilver Thunderbolt 15.25" x 19"?

Re: Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel

Yes, weighted makes quite an impact. Add average adult (200# plus their gear)) and pull a tube and you're talking 200 to 400 rpm reduction. Size your prop to have the weight, but be careful when they're not there.. that 200-400 rpm is now going to be an increase.

Careful when you state, "The goal is to improve overall propeller efficiency, speed and also fuel consumption."
*the faster you plane, the more efficient you can run
*the faster you go, the more fuel you will consume

YOU CAN'T EAT YOUR CAKE AND HAVE IT TOO! Meaning, you do't get the best of everything in one prop. Sounds to me, you are less concerned about being a speed freak, you want to get on plane prepared for water-sports, and you would rather drive efficiently instead of being at top speed. If this is true, go with a 4-blade 19P. Faster planing, slower planing speed, more stable steering, slight loss at top end.

It is your expense for the prop and your boat to take care of.

We will always give our input and advice, but remember what it cost you; it may only be worth that much!

Good luck and let us know how it goes!

Re: Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel

I realize the trade off is to find the right balance for different kind of use.
I ordered the 3-blade SS Stiletto Advantage 14.25" x 19" because the 4-blade 19P from Stiletto (Bay Pro III) does not seems to be designed for stern drive but rather for larger offshore and center console boats, I assume to aggressive for my boat. I should have gone to the 4-blade 18P (Bay Pro II) but I did not want an additional 1" pitch decrease.

I'll let you know how it goes.

Re: Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel

I ordered a SS Stiletto 14.25" x 19" and finally received a SS Turbo 1 14.25" x 19" from Precision Propellers (same manufacturer, some people claim only the sticker changes).

I could try the prop loaded with 2 persons, WOT 52 mph (speedo) @ 4800 RPM (still 200 below max engine RPM).

It is definitely the good size for my boat because the prop has a lot of cupping.

I could also make the following observations:
- Improved hole shot
- Greatly improved mid range acceleration
- No big difference with 21" for top speed and max RPM (less slip), engine revs slightly higher at mid range for the same speed, I assume it can negatively impact the fuel mileage, but I do not have enough experience for now.

Maybe I could get some additional benefits (overall good performance and mid range fuel economy) from a 20" or 21" high performance propeller with thiner blades (increased revs). I am thinking about the Mercury Enertia.
Any opinion welcome.

Re: Four Winns H200 Volvo Penta 5.0 GXi - Switching from aluminum to stainless steel

Captain Man said:

I ordered a SS Stiletto 14.25" x 19" and finally received a SS Turbo 1 14.25" x 19" from Precision Propellers (same manufacturer, some people claim only the sticker changes).

I could try the prop loaded with 2 persons, WOT 52 mph (speedo) @ 4800 RPM (still 200 below max engine RPM).

It is definitely the good size for my boat because the prop has a lot of cupping.

I could also make the following observations:
- Improved hole shot
- Greatly improved mid range acceleration
- No big difference with 21" for top speed and max RPM (less slip), engine revs slightly higher at mid range for the same speed, I assume it can negatively impact the fuel mileage, but I do not have enough experience for now.

Maybe I could get some additional benefits (overall good performance and mid range fuel economy) from a 20" or 21" high performance propeller with thiner blades (increased revs). I am thinking about the Mercury Enertia.
Any opinion welcome.

Click to expand...

Actually there is more difference between the Stiletto and the T1 than you think. If you are not happy with the T1 call and use the exchange program and you can switch it for something else that PPI makes. If you were looking for a good all around prop the T1 is hard to beat though. We also have a pretty knowledgeable tech support and they might be able to help you switch the T1 for something that will put you where you want to be.

Good Luck!