5-Blades
03-29-2004, 07:01 PM
#1
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5-Blades
Wondering how the 5-blades will work on my application. Running a 1.36 Imco Extreme SC with a standoff box, 103 @ 5700 on a lab 30 Brovo 1. You can check out picks of the drive height.
http://community.webshots.com/album/83701358qOJGlb
http://community.webshots.com/album/83701358qOJGlb
03-29-2004, 08:35 PM
#4
speel chekk this fokker!
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LOVE my 5 blade hering.
Hell my setup is coservative and kinda slow by all means but the herring really really helped picked up soem speed and my slip numbers dropped significantly.
Hell my setup is coservative and kinda slow by all means but the herring really really helped picked up soem speed and my slip numbers dropped significantly.
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Pardon me, while I whip this out!
Pardon me, while I whip this out!
03-29-2004, 10:12 PM
#5
Hey John,
Draw a line across side to side from the inside corner of the sponsons and then see where the prop centerline fall relative to it, that is inches above the line or inches below. I was running 100 at 5100 with 30" so your slip is up a bit.
Draw a line across side to side from the inside corner of the sponsons and then see where the prop centerline fall relative to it, that is inches above the line or inches below. I was running 100 at 5100 with 30" so your slip is up a bit.
03-30-2004, 06:39 AM
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John,
The 5 blade would help bring the slip down and maybe even pick up some top end speed as well but; Your WOT rpm should be running around 6500 with the cam in that motor. One reason for the high slip number is due to your WOT rpm being too low.
Your dyno sheet shows the motor still making hp beyond 5700. The max torque is at 5300, your WOT should be about 1200 rpm above max torque. Since your WOT is only 400 above max torque the drive train is "torque loaded" which tends to lift the stern, bringing the prop higher out of the water and increasing the slip.
If you are interested in trying a 5 blade let us know and we can send one out to you. Ideally your slip should be in the 6-8% range in your application.
Matt
The 5 blade would help bring the slip down and maybe even pick up some top end speed as well but; Your WOT rpm should be running around 6500 with the cam in that motor. One reason for the high slip number is due to your WOT rpm being too low.
Your dyno sheet shows the motor still making hp beyond 5700. The max torque is at 5300, your WOT should be about 1200 rpm above max torque. Since your WOT is only 400 above max torque the drive train is "torque loaded" which tends to lift the stern, bringing the prop higher out of the water and increasing the slip.
If you are interested in trying a 5 blade let us know and we can send one out to you. Ideally your slip should be in the 6-8% range in your application.
Matt
03-30-2004, 08:45 AM
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Matt, I have been staying half in tune with the 5 blades available. Herring, Mercury and Hydromotive are the brands I am familiar with. My rev limiter is set at 5850 and I would like to prop as close to it as possible. I cruise at 3500 at 65 mph as it hits the hardest from about 60-90. The last 5-7 mph takes some distance to hit, but it will run consistantly at 100 with 3 people 3/4 tanks and a full cooler. It pops right onto plane with ease and I do not blow out at all.
Let me know what you recommend.
John
Let me know what you recommend.
John
03-30-2004, 09:13 AM
#10
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Cobramarty, you are dead on, my mistake. I went right past those low numbers.
John, your rev limiter is set just right. In your case I think a P5X 28 or 29 would put you at about the same WOT rpm you are now. Acceleration will improve and your cruise speed should improve about 7 or 8 mph compared to the Bravo 1 lab you have now. The nice thing about the P5X is the way it runs right out of the box. A stock P5X should get you at about the same top end, if not better, than your lab Bravo 1 but with all the advantages of a 5 blade.
If you are interested in trying one give us a call.
Matt
John, your rev limiter is set just right. In your case I think a P5X 28 or 29 would put you at about the same WOT rpm you are now. Acceleration will improve and your cruise speed should improve about 7 or 8 mph compared to the Bravo 1 lab you have now. The nice thing about the P5X is the way it runs right out of the box. A stock P5X should get you at about the same top end, if not better, than your lab Bravo 1 but with all the advantages of a 5 blade.
If you are interested in trying one give us a call.
Matt
