Looking for Prop
#22
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Re: Looking for Prop
Originally Posted by formula377
If anyone is interested...
I have been researching my ARS off about props recently! Here is a little comparison I got from Throttle up about props HP and RPM. Here is what I gathered...
Your boat should have the biggest prop it can run so that WOT RPM matches your peak HP RPM for maximum top speed. If you have a stock engine the Mercruiser WOT RPM reccommendations should be fine. If you have modified your engine and have DYNO results your doing even better.
Here is the scenerio...
89 357 SR-1 TRS drives 454 420 hp
23P Mirage 5800RPM 60 MPH (Mercruiser reccommended WOT RPM 5000-5200RPM) Obviously needs more prop and should not be run past 5200RPM.
A 23P Mirage plus should run 5650 RPM (Gain MPH in cruising and some top end also)Reason: More cup on the blades
A 22P Bravo 4 blade 5600RPM (Gain MPH in cruising and some top end also)Reason: 4 blades = More bite in water gives boat more lift which equals less drag and more speed all around.
This engine combo probably could use :
25P Mirage PLus = 5250RPM or
24P Bravo 4 blade = 5200RPM
There is also one more thing to consider: there is a difference between Bow lifting and Stern lifting 4 blade props. My opinion seems to be more owners of older NON-stepped hulls can use a Stern lifting props like Hydromotive 4 blade. Newer stepped hulls are better off using the 4 blade bow lifting props like the Bravo 1.
This is what I have gathered. I would like to try some props this summer to see what kind of actual results I can get in the real world. Moving back to LOTO this summer, had enough of NY cold.
And this is my .02 ! Feel free to scrutinize and correct. Im only human.
I have been researching my ARS off about props recently! Here is a little comparison I got from Throttle up about props HP and RPM. Here is what I gathered...
Your boat should have the biggest prop it can run so that WOT RPM matches your peak HP RPM for maximum top speed. If you have a stock engine the Mercruiser WOT RPM reccommendations should be fine. If you have modified your engine and have DYNO results your doing even better.
Here is the scenerio...
89 357 SR-1 TRS drives 454 420 hp
23P Mirage 5800RPM 60 MPH (Mercruiser reccommended WOT RPM 5000-5200RPM) Obviously needs more prop and should not be run past 5200RPM.
A 23P Mirage plus should run 5650 RPM (Gain MPH in cruising and some top end also)Reason: More cup on the blades
A 22P Bravo 4 blade 5600RPM (Gain MPH in cruising and some top end also)Reason: 4 blades = More bite in water gives boat more lift which equals less drag and more speed all around.
This engine combo probably could use :
25P Mirage PLus = 5250RPM or
24P Bravo 4 blade = 5200RPM
There is also one more thing to consider: there is a difference between Bow lifting and Stern lifting 4 blade props. My opinion seems to be more owners of older NON-stepped hulls can use a Stern lifting props like Hydromotive 4 blade. Newer stepped hulls are better off using the 4 blade bow lifting props like the Bravo 1.
This is what I have gathered. I would like to try some props this summer to see what kind of actual results I can get in the real world. Moving back to LOTO this summer, had enough of NY cold.
And this is my .02 ! Feel free to scrutinize and correct. Im only human.
Note they make 2 models Quad-IV and Quad-IV-X. The standard Quad is a stern lifting prop ala mirage which is what you want. The "X" model is their copy of the Bravo 1 - a bow lifting prop that typically works best w/ stepped hulls.
Also I have been told that TRS doesn't like to be "overloaded" with a big prop, and it is probably best to keep the RPMs up a bit, say top out between 5200-5300. I spoke to an engineer at Hydromotive, and he said that people used to race TRS drives pretty much stock at 6000 RPM, so the drive can handle it, and the internals actually "prefer" RPMs rather than extra prop shaft load. Again this was his experience, but seems to make sense from everything else I've heard about those drives. So not that you want to spin your motors that high, but possibly stick to the higher RPMs. Actually those motors make peak HP around 5600 from what I heard too. I am trying to prop mine to somewhere between 5200-5300.
Getting back to the original ?, I'd suggest testing either a Bravo-1 or Hydromotive 4 blade on that boat since it is a single. Should provide more hookup, thus better midrange and handling.
#23
Re: Looking for Prop
Yes Yes and Yes
I agree with the bravo for stepped hulls and there are 2 styles of Hydro's.
Test before buying if you have that luxury.
Anyone wanna lend me some Hydros this summer at LOTO for a trial run???
Thanks for all the insight!
Love this website!
I agree with the bravo for stepped hulls and there are 2 styles of Hydro's.
Test before buying if you have that luxury.
Anyone wanna lend me some Hydros this summer at LOTO for a trial run???
Thanks for all the insight!
Love this website!
#24
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Re: Looking for Prop
Just in case you haven't already made your decision yet, one of your main items you should consider is just what do you plan to do with your boat. I own a 242LS also and have been in your place. I do alot of boat travel, carrying heavy fuel and gear loads. I run a 4 blade Hydromotive Quad IV 22 . I get plenty of bow lift and pull out of the hole farely easy. we built the stock 502 mag for it and with this type load, if fuel consumption is in any of your questions it clicks around 15 to 16 gallons a hour at 3200rpms
I also keep a labbed 22 mirage 3 blade for play time, It loses very little for the hole shot and spins 5300 easy, On a low tank of gas and myself it gets to 68 on the gps.
Keeping in mind these were not built for incredible speed, they have a large comfortability issue built in instead.
They may look fast, but without a supercharger the boat needs to be put on a diet. HEAVY
I also keep a labbed 22 mirage 3 blade for play time, It loses very little for the hole shot and spins 5300 easy, On a low tank of gas and myself it gets to 68 on the gps.
Keeping in mind these were not built for incredible speed, they have a large comfortability issue built in instead.
They may look fast, but without a supercharger the boat needs to be put on a diet. HEAVY
#25
Re: Looking for Prop
Cleaster, how did you make out with that mirage plus 19p from Darin. I just read an old post and was wondering how the speed and RPMs are. I am in the market for a prop for my my 1987-242-454-alpha drive 1.47.
Thanks
Thanks
#26
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Re: Looking for Prop
1987-242,
The 19" Mirage "Plus" that Darin labbed for me was the answer! It works perfectly. I get out of the hole in 5 seconds, 8 seconds with 4 adults on board. I have been getting 60-62 MPH, with perfect trim @5000 RPM. The boat seems to like a little rougher water and performs the best with some waves! Darin's # is somehwere posted earlier in this thread. Good Luck!
The 19" Mirage "Plus" that Darin labbed for me was the answer! It works perfectly. I get out of the hole in 5 seconds, 8 seconds with 4 adults on board. I have been getting 60-62 MPH, with perfect trim @5000 RPM. The boat seems to like a little rougher water and performs the best with some waves! Darin's # is somehwere posted earlier in this thread. Good Luck!
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