Solas Amita props

[dan t.]

First of all, boat- 1992 Bayliner 2452, 24 ft, 6000 lb fully loaded for a weekend
Power- 350 chev about 280 hp
Leg-Alpha 1 Gen II 1.65 ratio
Current prop-Quicksilver 48-11324-18 aluminum 15 1/2 x 18 with added cup
Cruise at 22 knots @3400 rpm, wot-4900
Problem- would like to drop 200 rpm at cruise
Prop I am considering - Solas Amita 3-E plus, #511-153-19, 15.3 x 19
If any one has used one of these I would like to hear your opinion, also any other thoughts or recomendations, yea I know I should regear the leg to 1.5 but thats not in the budget this year.
Thanks Dan

 

[dan t.]

Re: Solas Amita props

Nobody have anything to say? Someone must have used this prop.

 

[steelespike]

Re: Solas Amita props

What is the speed at wot? Boats aren't like cars.lowering rpm with a prop change usually isn't suggested unless rpm is excessive.
Marine engines work hard like they are pulling a trailer up a never ending hill.If you increase pitch its like forcing it into over drive.
The motor should be able to rev freely within its rpm range.
If you want to optimise your mid range performance a 4 blade would probably be a better choice.
It should also stay on plane better at reduced throttle.Should handle better at speed and at the dock.
I think your wot rpm should be about 4600 the 18" 4 blade should put it closer to that figure.
Top end may be reduced a little.

 

[dan t.]

Re: Solas Amita props

4blade, not a chance, been there, done that, a $250. experment that made things worse, Dont remember exactly what the wot speed was, realy dont care, I never run there. Wot rpm is 4900 which is too high should be around 4600, I would be happy to get my 22 knot cruise down to 3200,which a 1 in pitch increase should do. I was just wondering if anyone had used this particular Solas prop? BTW at cruise 3400 rpm I am pulling 10 in of vacuume so the motor is not working that hard.

 

[steelespike]

Re: Solas Amita props

Solas props generally have good results.
If you increase pitch your hole shot will likely be slower and vacume lower but give it a try.
May also become harder to keep on plane at lower rpm.
If the 3E plus is ss then there could be an acroos the board improvement over the al prop
Its difficult to estimate prop changes when going to ss. not heving your wot rpm and speed makes it difficult to evaluate your present setup.
Generally a 1" pitch change will lower rpm "about" 200.

 

[Tail_Gunner]

Re: Solas Amita props

4blade, not a chance, been there, done that, a $250. experment that made things worse, Dont remember exactly what the wot speed was, realy dont care, I never run there. Wot rpm is 4900 which is too high should be around 4600, I would be happy to get my 22 knot cruise down to 3200,which a 1 in pitch increase should do. I was just wondering if anyone had used this particular Solas prop? BTW at cruise 3400 rpm I am pulling 10 in of vacuume so the motor is not working that hard.

Dan would you articualte on that a bit...Four bladed props should be superior to a 3 blade in heavy pushing You are @ 29% slip which is a tad high....You may want to check your speed with gps and your tach...boat tachs along with speedo's are great looking but not to reliable as a whole...

 

[dan t.]

Re: Solas Amita props

Thanks for the input Tail gunner, speed is gps,tach is stock boat, havent checked it that high but up to 3000 it is pretty close to my digital Snap On timing light. The proposed new prop is aluminum. Now as for that *@#%$ four blade, 4 years ago when I still had a 305 motor I was running a 16x16 3 blade aluminum prop, I wanted better hole shot and to hold on plane at lower speed which a 4 blade is supposed to do. I bought an Alpha 4 15x16, the results were bad, time to plane trippled,planing speed went up, cruise rpm at 20 knots went from 3600 to 4000. I cant even sell the POS, 2 people have tried it with similar results, BTW I got a prop shop to add some cup to the 16x16, it did everything I wanted to acomplish,

 

[fishrdan]

Re: Solas Amita props

I bought an Alpha 4 15x16,,, I cant even sell the POS...

Check your PM's

 

[Tail_Gunner]

Re: Solas Amita props

Solas props are great props they should work well. Notice in Walleyeheds prop test thread the mich props did very well in heavy pushing..As to the four blade what you desrcibed was over propping (to big) then compounded the issue with cupping. That cupping turned that 4 blade into a 17p prop maybe more with a 305 on a 8000lb boat....Way to big..Example 2800lb boat..800lbs weight...200hp...1.66 gearing..18p 4 blade is the ticket...almost the exact same power train half the weight.

 

[dan t.]

Re: Solas Amita props

Tail gunner,you read my post wrong, the reason for poor acceleration was slippage not over propping, the 4 blade didnt have any bite at low speed, rpms went up ,the boat went slower, this was confirmed on 2 other similar boats. I didnt add cup to the 4 blade ,I added to the 16x16 3 blade which then performed exactly as I wanted it to.
fishrdan check your PM's