3 blade propeller vs 4 blades
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Category: General Correct Craft Discussion
Forum Name: Common Questions
Forum Discription: Visit here first for common questions regarding your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=9963
Printed Date: November-23-2024 at 8:00pm
Topic: 3 blade propeller vs 4 blades
Posted By: kapla
Subject: 3 blade propeller vs 4 blades
Date Posted: March-28-2008 at 2:31pm
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Hi
I own a 1992 ski nautique with standart pcm351 with te original 3 blade propeller. I use the boat for wakeboarding adding up to 1800lb of weight to create a nice wake. I have no problems with this set up, but I wanted to know if a 4 blade prop would be a good upgrade increasing performance and fuel effiency? Thanks... |
Replies:
Posted By: 79nautique
Date Posted: March-28-2008 at 2:40pm
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not sure if it will help much other than getting out of the hole. Typically the 4-blades lose top end speed while adding low end hole shot. With the added weight and the four blade allowing the engine to work a little easier you might see a little better performance and fuel savings while it is loaded down and you are boarding but when your not then I think it goes against you in regards to fuel savings.
What's your take Tim? also is a there a specific model/brand you are looking at? ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique |
Posted By: kapla
Date Posted: March-28-2008 at 2:50pm
| Actually no brand in mind, so wich is a good pick? regarding performance w/o weigth my cuise speed is of 2300 rpm to get to the boarding zone in a 30 minutes ride. So at that speed can i notice the fuel efficiency lack? |
Posted By: TRBenj
Date Posted: March-28-2008 at 3:01pm
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Your 2 goals (performance and fuel efficiency) are in opposition to each other.
To increase performance (better holeshot with weight, speed holding, etc), you'll want to increase RPM's by decreasing prop pitch. To improve fuel efficiency, you'll want to decrease RPM's by increasing prop pitch. A 4-blade might get out of the water a little quicker than a 3-blade if everything else was held equal (diameter, pitch and cup), but thats not exactly the case. The modern 3-blades offered by Acme (470, 1442)have a touch less pitch than the 4-blade (Acme 422, OJ 428), so theyre a better all around prop (IMO), especially for a weighted boat. They get out of the water quicker and end up being faster on the top end as well. That being said, if youre currently running the stock prop (likely a 14x16 3-blade Federal), you should a big improvement in performance (and possibly efficiency) with ANY of the new Acme's or OJ XMP's. Theyre all good props. My personal choice if I were using the boat like you would either be the Acme 1442 or 470. ------------- |
Posted By: kapla
Date Posted: March-28-2008 at 3:11pm
| Thanks on the tips!!! |
Posted By: brittcrowell
Date Posted: May-13-2008 at 1:38am
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Good Info,
Years ago I ripped the bottom off my '93 ski, in Colorado. In getting all the work done we went down like half a size on the prop to help with the high density altitudes that we delt with on the front range, 5000ft, altitude densitys up to 8000ft (75% power). Mostly we had a hard time with the carburated boat mantaining a good wakeboard speed. Now I've moved back to Alabama, re-jetted the carb, again, but I'm sure the smaller prop is hurting my efficency. Been thinking about stealing my buddys dad orginal prop to help out the situation, their boat only sees the water 2-3 times a year since my best friend growing up on the lake with, still lives in Colorado and doesnt come home but once a year. BTW found my orginal prop 6 weeks later: http://www.brittcrowell.com/2002/2002-08-07_we_dont_need_no_prop/ - http://www.brittcrowell.com/2002/2002-08-07_we_dont_need_no_prop/ Britt |
Posted By: jeffinohio
Date Posted: May-19-2008 at 3:12pm
| I HAVE THE SAME BOAT AS YOURS. A 92 SN. I HAVE USED BOTH THE OJ XMP 4 BLADE AND THE ACME 3 BLADE. MY BOAT PERFORMS BETTER WITH THE OJ XMP 4 BLADE. THE OJ HAS JUST AS GOOD A HOLE SHOT AND ACTUALLY RUNS 1.5 MPH FASTER TOP END. THE ACME RUNS AT A HIGHER RPM TO KEEP THE SAME SPEED. IT USED MORE GAS. THE OWENER OF OJ (KEVIN JOHNSON) IS ALSO VERY HELPFUL. HE WILL RETUNE YOUR PROP FOR OPTIMUM PERFORMANCE. |
Posted By: boat dr
Date Posted: May-19-2008 at 3:43pm
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Eric is the owners name, his wife is Sue. All other info is correct and spot on.
They are a family owned and operated repair and manufacturing facility.Service is top notch and knowledge is premium......Boat dr ------------- boat dr /diaries/details.asp?ID=4631 - 1949 Dart /diaries/details.asp?ID=1533 - 1964 American Skier |
Posted By: eric lavine
Date Posted: May-19-2008 at 4:00pm
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I thought Billy was his name-o ------------- "the things you own will start to own you" |
Posted By: boat dr
Date Posted: May-19-2008 at 8:31pm
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Eric , different Eric, same name less BS.....
And that is Mr. Billy to you.......... Boat dr ------------- boat dr /diaries/details.asp?ID=4631 - 1949 Dart /diaries/details.asp?ID=1533 - 1964 American Skier |
Posted By: ejojprop
Date Posted: May-05-2009 at 2:16pm
Hey Doc, Just to clarify, we are family owned and operatated. Although Ms. Sue is not my wife, she is the Boss here in many ways. Thanks Billy for your business too. New to the forum here and looking forward to helping with advice and clarifications when I can. Eric |
boat dr wrote:Posted By: Kristof
Date Posted: May-05-2009 at 5:06pm
Mr Billy, that one really made me ROFLOL...! ------------- - Gun control means: using BOTH hands! - Money doesn't make one happy, but when it rains cats and dogs, it's still better to cry in a Porsche than on a bicycle... |
Posted By: brittcrowell
Date Posted: May-05-2009 at 5:40pm
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Well I guess I'm back on this too, I do have the ACME 470 prop that is 12.5x15 and I'm not happy with the fuel burn I'm getting for the type of skiing/boating I'm doing these days. So I guess I'll put this up for sale/trade in case someone else wants a 470 ACME prop.
Britt ------------- '93 Ski Nautique (needs new interior) |
Posted By: oledawg
Date Posted: May-10-2009 at 3:03am
OK, so I am still confused. I just bought a 87 CC Riviera that is said to have 13/1 4 blade prop on it and a 15/1 3 blade extra. Previous owner said that the 15/1 should be faster top end but slower out of the hole, which says to me that the 15/1 is also better on gas all things being equal. Thoughts?  ------------- "To profit from good advice requires more wisdom than to give it" |
Posted By: Luchog
Date Posted: May-10-2009 at 10:31pm
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Actually it depends on how and what are you using your boat for.
generally speaking less rpms mean lower consumption, but if you are really weighted and running low rpms then you're loading the engine, it will burn MUCH more gas and probably suffer harder wear. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique Commander 351W |
Posted By: oledawg
Date Posted: May-10-2009 at 10:37pm
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OK, what I am gathering from all of this is that no one really knows if a 3 blade or 4 blade is better. On top of that, still don't know if a 13/1 or a 15/1 is faster on top end. ------------- "To profit from good advice requires more wisdom than to give it" |
Posted By: oledawg
Date Posted: May-10-2009 at 10:39pm
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Also for this exercise I am interested in the maximum top end speed. With a 454 I have NO problem with decent holeshot.
Thanks, ------------- "To profit from good advice requires more wisdom than to give it" |
Posted By: chessloveedit
Date Posted: May-11-2009 at 12:29am
| Hey I was doing some research today on which prop is better. 3 or 4 blade. On wakeworld.com I read that a lot of the wakeboarders prefer newer acme 3 blade. I am not choosing brands its just the one people happened to be talking about. go check it out. lots of info on the different props |
Posted By: Luchog
Date Posted: May-11-2009 at 6:28am
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Oledawg, the thing is your not proving accurate info on your boat performance with the current prop. Neither is clear what you mean by "13/1 or 15/1) we need to know your normal operating rpms/speed and wot rpms/speed data to help you with the prop search
usually the bigger the pitch the faster your boat will be as long as it allows the engine to perform at maximun reccomended rpms. But again, we need your boat's performance data. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique Commander 351W |
Posted By: oledawg
Date Posted: May-11-2009 at 8:45am
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OK, seems the issue is that I don't know the right question to ask. No problem. I will leave the current prop on, the 4 blade, until I am more knowledgeable! Definitely not going to buy a new one! Thanks for all of the attempts.
Best, ------------- "To profit from good advice requires more wisdom than to give it" |
Posted By: chessloveedit
Date Posted: May-11-2009 at 3:27pm
| Kapla. I called acme and they told me exactly what I need based off what engine/trans I have and the sport ill be doing. TR benj is also a big help. Its all pretty easy if you just call. If you want wakeboard parts advice go to wakeworld.com. The thing to remember is that a lot of people have been through it already and know what is best. |
Posted By: Luchog
Date Posted: May-11-2009 at 4:21pm
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On the wakeoworld site, there's this guy named Karl DeLoof, he owns a boardshop called Boarditup.com, he's one of the larger propeller sellers for ski boats around, when re-propping for wakeboard he's the man to ask over there. He's a wakeboarder himself and understands both mechanical and boarding perfomance. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique Commander 351W |