hwsiii, Dhadley and/or Kenny - opinions...

[X-Treme]

1. 2008 Glastron GXL 185 SF
2. Length - 18', Beam - 91" / Transom Width: 86", cant find base weight, but
listed weight is 2740 lbs w/4.3 GL Volvo Penta
3. 3-4 people usually (500-800lbs), Fuel - 25ish Gallons
4. Mostly fishing, occasional tubing
5. Transom Deadrise: 21?
6. 2008 Volvo Penta 4.3L GXi-G
7. 225HP, 1.60 Gear Ratio
8. WOT - 4400 - 4800
9. n/a
10. Mercury Black Max 14.5" X 19P
11. 4650 RPM, 32 MPH measured on speedo

Also, another peice of info you may need - I do most of my boating at about 2200ft elevation.


What I really wanna know is.... Should I just stay with the prop I have, or should I go to a 4 or 5 blade, and or stainless steel prop? Wouldn't mind if it popped out of the hole a little quicker when loaded.

 

[hwsiii]

Re: hwsiii - opinions

Re: hwsiii - opinions

X-Treme, I show a 1.66 gear ratio for your outdrive instead of a 1.6, would you check this for me. Was your WOT speed at 2,200 feet or was it at sea level and how many people were in the boat at that time. I would like to have a GPS speed at WOT, because right now you are showing an astronomical prop slip of 39% and that is highly unusual to say the least.
The data that I get is the basis for the calculations to pick the correct prop for your boat, if it is not good data the results are not very good either. Please try to do some speed test for me writing down the RPM and speed starting at 3000 RPM through WOT at 250 RPM increments so I can have good data for a recommendation. The numbers you gave me I do not believe are good numbers on speed and WOT because you should be able to go faster, and definitely NO that is not the right prop if those numbers are close.

H

 

[X-Treme]

Re: hwsiii - opinions

Re: hwsiii - opinions

According to the sticker on the drive, it is a Volvo Penta SX-A and gear ratio is definitely 1.60, and NOT 1.66 as you have stated and all info that I have been able to find also states.

Those numbers that I gave you were ALL at 2200ish ft elevation, and with 4 people in the boat (approx. 675 lbs)

I will be out on the lake today and will get my gps working and see if I can get you some numbers.

 

[X-Treme]

Re: hwsiii - opinions

Re: hwsiii - opinions

Allright....got out today and found out that the speedo on my boat is NOT EVEN CLOSE.

With 2 people (Approx 400lbs) and about 20ish gallons of fuel, I topped out at 4800rpm WOT and GPS'd at 45mph.

Hope this helps you.

 

[hwsiii]

Re: hwsiii - opinions

Re: hwsiii - opinions

Chris, I would say you are doing very well with that combination at 2,200'. You prop slip is only 17% with that last run. In my opinion I would buy either a stainless steel 3 blade or 4 blade prop since you do some tubing and it should bring your prop slip percentage down. I will give Dhadley or Kenny some time to chime in on this and make a recommendation on exactly which prop you ought to buy, since I have found out their qualifications with props. They are years ahead of me in making those type of decisions. Hopefully we can get one of them to tell you which prop would best suit your needs for your uses. Here are the numbers I have.

Prop Picker

Prop Slip

H

 

[X-Treme]

Re: hwsiii, Dhadley and/or Kenny - opinions...

Thanx again. Looking forward to hearing from Dhadley and/or Kenny.

 

[Tail_Gunner]

Re: hwsiii, Dhadley and/or Kenny - opinions...

11. 4650 RPM, 32 MPH measured on speedo

Nope not even...if that's the case true mph... you have something seriously wrong

 

[hwsiii]

Re: hwsiii, Dhadley and/or Kenny - opinions...

Just giving it a bump to see if dhadley will find it.

H

 

[Dhadley]

Re: hwsiii, Dhadley and/or Kenny - opinions...

Been watching but the one thing I didn't see was what the condition of the current aluminum prop is. Or if it's ever been rebuilt. If those numbers are loaded and at 2200 ft then it's not bad. Kenny is the one with elevation experience (rumor has it that it sometimes snows when you get too far above sea level. I'm fine right here.).

My guess is that you could go to a good ss prop like a Stiletto in the same pitch. As long as we're comparing all this to an aluminum prop in good shape.

 

[hwsiii]

Re: hwsiii, Dhadley and/or Kenny - opinions...

Thank you Dhadley.

H

 

[X-Treme]

Re: hwsiii, Dhadley and/or Kenny - opinions...

The prop used for testing was brand new out of the box. Any recommendations on which model of Stiletto?

 

[Tail_Gunner]

Re: hwsiii, Dhadley and/or Kenny - opinions...

18p 4blade stilletto max midrange lower planing speeds
19 pitch three top speed there is only one three blade stilletto