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78skier
03-07-2006, 09:30 PM
hello
I need a new prop on my 78 stars and strips can someone tell me the pros and cons of diffrent props and what would be the best for my boat. I would like to keep the speed as well as gain some toarque. Also brass or stainless I know that brass is a little forgiving and stainless not so much if you hit something with it. Is there anything else I should keep in mind :confused: :steering:

erkoehler
03-07-2006, 09:33 PM
Check out the FAQ thread, there is a link to a whole prop test/comparison.

ski_king
03-07-2006, 09:38 PM
Yep check out the FAQ.

You didnt say if it was 1:1 or 1.5:1, although I dont think the reduction drive was introduced until 79 or 80. I think you will find a CNC 3 blade to be the way to go, BICBW

BrianM
03-07-2006, 09:48 PM
Acme #541 or OJ XMP 13 x12. Both CNC three blades.

east tx skier
03-07-2006, 11:35 PM
PM me your email addy and I will email the prop test to you tomorrow if you're interested in it. It is no longer hosted. Still looking for a new home for it.

PendO
03-07-2006, 11:37 PM
PM me your email addy and I will email the prop test to you tomorrow if you're interested in it. It is no longer hosted. Still looking for a new home for it.

easties prop comparison is a good read!

Kevin 89MC
03-08-2006, 12:10 PM
FWIW, on my '89 PS w/ 1:1, when I switch between my 3 blade & 4 blade (both brass), this is what I notice when I run the 3 blade: a bit more rooster tail/prop wash, less of a hole shot, a bit more top speed (~1 mph), a bit more vibration (but not much, I may be imagining it). Boat came with the 3 blade, switched to the 4 a few years later. I keep the 4 blade on, unless it's getting worked on, which is rare. I don't need the added hole shot the 4 gives, or the extra 1 mph the 3 gives, but the wake with the 4 is better I think. Maybe it's all in my head though!
I should compare them back to back on the same day to get a better feel for the difference. What I really should do is a blind test so I not biased. In all, both are fine, but there are some subtle differences, and I do recommend the 4 blade.
My :twocents:

east tx skier
03-08-2006, 12:14 PM
Kevin, are these CNC'd or hand finished props?

G-man
03-08-2006, 12:16 PM
Talk with Bill at Acme props, a three blade on that will be great.

Kevin 89MC
03-08-2006, 12:17 PM
Kevin, are these CNC'd or hand finished props?
Uhh, not sure. How do I tell? My guess is the 3 blade is the factory original, and the 4 looks just like it (color, stampings, etc) :confused:

east tx skier
03-08-2006, 12:22 PM
Probably hand-finished (the factory original definitely is). CNC'd props are a different ballgame. 3 blades are vibration free and, in some instances, have the same surface area as the four blades. Great acceleration with no loss of top end.

With hand-finished props, I'd say your observations are dead on accurate though.

TMCNo1
03-08-2006, 03:43 PM
On our '89 1:1,I ran a polished, rebalanced and chromed 3 blade nibral OJ for 13 years, in 2001 Eric @ OJ built me a 4 blade nibral with the polished finish and what a difference, it was so smooth and what a hole shot with no loss in top end speed. In 2003 got a polished 4 blade from MC and had it repolished and it was that much better than the nibral 4 blade, first time out of the hole I threw my wife in the floor, it was super smooth and still no loss of top end speed, 43.5 mph with corrected speedos @ 4350rpm. Just as it is suppose to be!

jbfootin
03-08-2006, 04:06 PM
My findings were the same as Kevin's.

On my old '88 ProStar 190 I went from 3 to 4 blade. I lost 1-2 mph but had a better hole shot. I didn't need the top end, eventhough 80% of what I pull is barefooting, and the low end torque was nice.

edwinfuqua
03-09-2006, 11:25 PM
I have a 85 ProStar 190 with 454 HO, 420 HP 400 FtLbs flat torq. When I bought the boat it had a SS LH 14"x20p 3 blade prop. I could turn 6K RPM easily and also turned the blades blue. Top speed was about 48MPH. I changed to a CNC LH 14.5"x22p 4 blade prop and the engine will only turn 4700RPM and but gets the same MPH. Seems like the fuel mileage is better now too. I wish I had got a 14.5x20p though and could run about 5K RPM but the slower RPM is safer on the engine and that is peak HP acording to the dyno. Good Luck. Edwin Fuqua edwinfuqua@yahoo.com

Brent
03-10-2006, 05:01 PM
.....................

AirJunky
03-10-2006, 05:42 PM
PM me your email addy and I will email the prop test to you tomorrow if you're interested in it. It is no longer hosted. Still looking for a new home for it.
Hey Doug,
Free pic/doc hosting here: http://www.zshare.net/

east tx skier
03-10-2006, 05:55 PM
Thanks, Bill. I'll look into it soon.

/edit. Okay, here's the link. (http://www.zshare.net/download/propeller-test-write-up-final-doc.html) Off to update the link in the FAQ.

Workin' 4 Toys
03-11-2006, 12:23 AM
If I could get my hands on a CNC 3 blade to comparo on my boat I would try it. But it seems the reading I do about it, always pushes me back to the 4 blade. I may be trying a CNC 4 blade to replace my OJ if I talk myself out of the stainless steel.
I have to know, has anyone ever tried powdercoating a prop on a ski boat? I have read it makes a difference on the hole shot and top speed. Not sure I am willing to try, just wondering.

stevo137
03-11-2006, 12:43 AM
If I could get my hands on a CNC 3 blade to comparo on my boat I would try it. But it seems the reading I do about it, always pushes me back to the 4 blade. I may be trying a CNC 4 blade to replace my OJ if I talk myself out of the stainless steel.
I have to know, has anyone ever tried powdercoating a prop on a ski boat? I have read it makes a difference on the hole shot and top speed. Not sure I am willing to try, just wondering.
I could see it on aluminum props but I don't think that there would be less coefficent of friction than stainless. I don't think that you would gain anything if you tried to powder the stainless and you won't get good adhesion.

Workin' 4 Toys
03-11-2006, 12:47 AM
I think Powdercoaters would disagree. I intend to ask Greg next time I stop in there, which might be next week. I was there today but forgot to ask. I believe he has his done.

stevo137
03-11-2006, 01:18 AM
I think Powdercoaters would disagree. I intend to ask Greg next time I stop in there, which might be next week. I was there today but forgot to ask. I believe he has his done.
The only thing that the powder will give you over stainless is color and even if you etch the prop, you still might not get good adhesion.
At this point, nothing beats nibral for ski boats...

Workin' 4 Toys
03-11-2006, 01:25 AM
The only thing that the powder will give you over stainless is color and even if you etch the prop, you still might not get good adhesion.
At this point, nothing beats nibral for ski boats...
Sorry, I was thinking of coating Nibral, didn't catch you were talking about stainless. I must have read that too fast.

stevo137
03-11-2006, 01:34 AM
Sorry, I was thinking of coating Nibral, didn't catch you were talking about stainless. I must have read that too fast.
No problem Toy's, I thought that you were talking about coating the stainless.

Workin' 4 Toys
03-11-2006, 01:37 AM
No problem Toy's, I thought that you were talking about coating the stainless.
In my mind I would like to comparo a 4 blade stainless, 4 blade Nibral, 4 blade Nibral coated, 4 blade CNC, and a 3 blade CNC.
But only if I got really good deals....And could sell them for what I paid after the test...;)

BTW, I thought you were in Mex.?

stevo137
03-11-2006, 01:45 AM
In my mind I would like to comparo a 4 blade stainless, 4 blade Nibral, 4 blade Nibral coated, 4 blade CNC, and a 3 blade CNC.
But only if I got really good deals....And could sell them for what I paid after the test...;)

BTW, I thought you were in Mex.?
Next week my friend! ;)

Now you got me thinkin'! I could easily powder my 4 blade to test.
I could see less coefficient of friction on powder versus nibral, not sure if any testing has been done though.
I have a 3 blade OJ that I can play around with too.

Workin' 4 Toys
03-11-2006, 01:50 AM
Next week my friend! ;)

Now you got me thinkin'! I could easily powder my 4 blade to test.
I could see less coefficient of friction on powder versus nibral, not sure if any testing has been done though.
I know a media blaster that would help to get it SMOOTH if you know a coater to help with the experiment.
I was actually thinking if I pull my 4 blade, and have it repaired and then coated, and then buy my new 4B-CNC or Stnlss, I would be 2:5 there...

stevo137
03-11-2006, 01:50 AM
I know a media blaster that would help to get it SMOOTH if you know a coater to help with the experiment.
I was actually thinking if I pull my 4 blade, and have it repaired and then coated, and then buy my new 4B-CNC or Stnlss, I would be 2:5 there...
PM your way.