Prop Recommendations

[mvn]

The stock prop has a slightly dinged/warped blade (was like that way when I bought the boat). We primarily use the boat for tubing/skiing/wakeboarding. The stock prop on the Volvo 4.3 GL-D SX is 14.25x19 4-blade and the tach is reading 4600 RPM at WOT.

I'm looking at the stainless steel Stiletto Bay Pro II 4-blade. They have a 14.25 x 18 and 14.25 x 20. Which one do you think I should get?

 

[steelespike]

Re: Prop Recommendations

As I understand it when you go to stainless you need to drop in pitch.
Someone should be along with some more detail.

 

[mvn]

Re: Prop Recommendations

I have more accurate information after this weekend. It seems that with Smart Tabs on, the engine is now turning 5000 RPM at WOT with a speed of just under 45 mph. Definitely over revving. After all of the reading I have done on this site, it looks like I might be OK with the 20". It should bring the engine speed back down to where it should be. Comments?

 

[WillyBWright]

Re: Prop Recommendations

logical

 

[Tail_Gunner]

Re: Prop Recommendations

I have more accurate information after this weekend. It seems that with Smart Tabs on, the engine is now turning 5000 RPM at WOT with a speed of just under 45 mph. Definitely over revving. After all of the reading I have done on this site, it looks like I might be OK with the 20". It should bring the engine speed back down to where it should be. Comments?

1.Well is the gl a 2 barrel or 4 barrel carb?
2.What is the weight of your boat?
3.Type of drive and gear ratio

For example i have a Wellcraft 186..18' 6"
1.220 hp efi
2.2800 lbs
3. 1.66 gearing

For that boat the 20 was dead on, but a 22 dropped it 500 rpm's. This much i can tell you Precison prop's let me exchange for 25.00 as long as stayed within the Baypro 11 line.Your awfully close to either prop but if you run with 4 or more people in inclined to say 18.... post the weight and gearing that should say it all...

 

[mvn]

Re: Prop Recommendations

1. 2 barrel, 195 hp V6
2. 2690 lbs. (I assume dry weight)
3. 1.79 ratio

Usually run with 500 to 600 lbs. of people and "stuff" and full tank of fuel (43 US gal).

On a distributors website, it shows Turbo props as exchangeable but Stiletto Bay Pro II not. I'll call Precision Props to get the real story.

 

[Tail_Gunner]

Re: Prop Recommendations

Lower gearing should get the prop turning along with the lighter weight, 35 hp is not much difference..... (20 pitch that is)

 

[mvn]

Re: Prop Recommendations

Thanks Tail Gunner.

 

[mvn]

Re: Prop Recommendations

Actually, I may have something else going on here. I noticed significant blowout in the corners while hauling tubes around. I could reduce it by trimming full down but couldn't eliminate it. On my next outing, I'm going to reduce the tab pressure to its minimum setting and see what happens (I've got 60 lb. actuators on hole #2). Ventilation seems to be the issue in tight turns. Could that explain the over revving at WOT (just thinking out loud)? And now that I think about it, I'm not sure if I can really trim the bow up enough at high speed in smooth conditions. Hmmmm........

I've also ordered a Turbo 2+2TH 14.25x20. If the 20" ends up being too aggressive, they'll exchange it for the 18" for a small fee.

Sure enough. A quick call to Nauticus and they confirmed too much pressure. Will change and hope I don't need to swap actuators.....but if so, not the end of the world!