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View Full Version : Advantages with a 4 blade prop


hkallestad
10-08-2009, 04:01 AM
89 PS190 with powerslot, would there be any advantages changing to a 4 blade prop? I have the 14 18 standard one now.

87MCProstar
10-08-2009, 07:22 AM
From my understanding and what I have been told it equals a better shot shot and holds speed better, but thats for the 1:1 not powerslot

hkallestad
10-08-2009, 07:31 AM
Ok thanks, I guess my original one would last a coupple of more seasons.

Thrall
10-08-2009, 05:03 PM
As I understand it, 4blade does what 87MC says, for a 1:1 or a 'slot, but at the cost of some topend speed.
Now though, teh 3 blade CNC machined props from OJ and ACME achieve the same goals with less vibration and less or no loss of top end.

TMCNo1
10-08-2009, 06:01 PM
As I understand it, 4blade does what 87MC says, for a 1:1 or a 'slot, but at the cost of some topend speed.
Now though, teh 3 blade CNC machined props from OJ and ACME achieve the same goals with less vibration and less or no loss of top end.


I'm running a 4 blade polished stainless OJ 13 X 13 on our 1:1, '89 and all I lost was about 250 rpm, but much better holeshot , no noticeable WOT speed loss and real smooth and quiet. There was a noticeable, more crisp throttle response at speeds between 20 and 36. First time out, I threw the wife in the floor on takeoff from idle, I won't do that again, without warning her!

88 PS190
10-08-2009, 06:53 PM
I'd call/email either OJ props, or ACME props, and tell them the particulars of your boat (including what prop it has, how many rpms its turning at what speed, if you run ballast/wakeboard, or primarily slalom with an empty boat) and then let them sell you whichever prop they recommend, I believe you will be happy.

Either way gonna be better than an old school jobber.

jwmiller
10-09-2009, 01:54 PM
I purchased this one this year to replace the 14x18 on my 1989 Prostar with powerslot and though I can't swear that the holeshot was any better. Acceleration and just overall feel was much improved.

http://www.propmd.com/pc-2892-983-135x175-105-cup-4-blade-new-close-out-price.aspx

John miller

DooSPX
10-09-2009, 02:07 PM
I have talked to Eric from OJ Props and he was very helpful and always willing to answer my dumb questions no matter how simple or redundent they may seem. My main goal with a new prop is improved holeshot, improved holding power, little to no top end loss (longline barefoot) and a flatter/softer roostertail from my powerslot.
For my application, he recommended the 4 blade 14x18 legend or the 4 blade 13.5x17.5 XMP CNC prop. I asked the difference performance wise and he said there is little to no performance advantage with the CNC, its simply a little more accurate. Since money is very tight right now, I will most likely go with the legend. but he will send you both to try and send the one you dont like back.

As soon as the funds are ready, I am going to call OJ ASAP.

88 PS190
10-09-2009, 04:53 PM
I asked the difference performance wise and he said there is little to no performance advantage with the CNC, its simply a little more accurate.

Accurate = less vibration. That being you draw a perfect prop on a computer, you cast it to the rough dimension. Then you have to finish shaping that prop, and balance it. On the CNC you are getting a very accurate finished prop. Which I feel like on small ski boats you will notice this more than you would on larger boats, so I think this is where you go for the CNC. Just a thought.