|I ahve a Bayliner 2050 with a 5.7 merc in it. Im runing 660 pounds in the rear and 450 in the front. The boat seems to struggle getting up and going now. Can anybody recomend what would be the best prop to put on it? It has a 3 blade 21p quicksilver on it now, is a 4 blade 19p the answer?|
I'm assuming you're at sea level. A 20' boat with 1,100 pounds and people is heavy. I'd think a 19" SS prop would do for you. Without getting into the 3 - 4 blades issues, SS will make more of a difference than anything. Thinner blades and if you get it power cupped, the performance is much better.
At 5K - 7K feet, I run a 17" prop. At 3K - 5K I'll use either a 19" or 21".
Just watch the WOT, and don't exceed the max RPM with a lower pitch prop.
|I tested back-to-back a Stainless and an Aluminium 23 pitch three blade props on my 18' 190 hp I/O. I notice no difference in top end or time to 20 mph using a stopwatch. Stainless is often described as being a better material, but unless the prop is thinned out to take advantage of the material properties, you'll see no difference. Arguments that stress stiffness are silly... boat bounce around far more that any prop flexes. |
And like I said two identical props, two materials ... no difference.
Everyone I spoken to on this board is pumped on four blades for hole-shot and wakeboard speed holding. It's all about blade area. Ski boat three blades usually have big blades when compared to outboard and I/O props. So whether its three big blades or four blades, blade area will help your low speed holding with a heavy load.
But I really have to agree with Matt on WOT rpm caution. If you can, talk a marina into letting you demo the prop.
Try one of these! http://www.piranhapropellers.com/
They retail for about the same price as a 3 blade aluminum prop but they really work! We have sold tons of them and just about everybody loves them. You might try a 20 pitch 4-blade first. The cool thing about these props is the replaceable blades. The hub has a lifetime guarantee and the blades cost around 18.00 each. You can have several sets of blades with different pitches on board.
In case anyone is wondering I do NOT have a financial interest in the company!
|I was looking at the piranha's too. Everyone seems to like them. |
Matt, have you ever heard of a down side to them?
|I have a piranha prop that fits a Mercury Alpha 1 and I don't use it anymore, it's a four blade prop. I was wanting to sale it. Here the deal, three of the blades are broken and would need to be replaced, I think they cost around $20.00 each, I have one replacement blade that's new and it's a 18" pitch. All someone would have to do is order the three 18" pitch blades and put them in the hub and install it on their boat. Let me know if you want this, I would sell the hub and one blade for $50.00 plus shipping. Let me know.|
|James, I disagree. The SS, power cupped props work much better than aluminum. |
Perhaps it has quite a bit to do with altitude also, but my 'side by side' with a 19" showed much better hole shot and a 4mph increase on top end. Also, it was much easier to hold speed with a skier.
|I'll chime in about piranha props, based on my experience with my 19ft i/o. I have a 4.3 and almost always run with a full boat (6-8 people) |
I used a 4 blade 20 pitch for some time, I liked it much better than the 3 blade alum 21 p. My WOT was about 4500 rpm and about 45 mph when loaded. With a light load, I could hit a bit over 50.
The biggest thing I didn't like (the only thing really) I can't really prove much...I think blades have a tendency to break without even hitting anything. I broke blades on 2 occasions, when I was pretty sure nothing hit the prop. I think the stress just added up. I've heard one other person mention this, but there are many more happy Piranha owners out there.
I now run a ss high-5, 19p. Top speed is less, rpm is higher, I don't (can't) go WOT much. Pulling is a bit better, and so is holding speed at ~20.
But now that I have perfect pass, I would buy an alum four blade if I need to replace the high five.
My point was that shape and size mater more than material. I used to race boats a bit and "cupping" always help our top end for sure.
Also, I don't think altidtude effects props.
A friend of mine got sold on Stainless for the wrong reasons (it was his prop I demo'ed). The dealer claimed just the materials alone would increase his speed etc, more his hair grow back in, etc. The two props were "identical" except for the material. And so was the performance.
|Yep, probably the progressive pitch is easier to attain with SS. Aluminum is pretty brittle. |
Altitude doesn't effect the props, true, but it really hits the HP! Something like 20% for each mile ( 5,280 feet )
LOL, make his hair grow back, attract women, etc!
|The really funny part is this friend also recommend these people for boat storage. But I may change next year... the dealer is begining to give me a funny feeling alround|
|Great thanks for the advice, I will demo some props for sure before outlaying the folding stuff. |
I do 90% of my running at sea level so it will be set up for that.
I really can't think of any downside unless top-end speed is a concern.
I have not seen any issues with regard to blade breakage other than hitting an obstruction. I know Piranha would stand behind any defect in workmanship.