Prop rake angle
04-23-2017 | 09:51 AM
#1
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From: Chicago
Prop rake angle
A greater rake angle generally improves the ability of the propeller to operate in a ventilating situation. Ventilation occurs when blades break and re-enter the water’s surface — such as occurs with 1) a Bravo sterndrive installed with a high “X” dimension, 2) a surfacing drive (NXT1, NXT6 SSM or M8) or 3) an outboard installed or jacked high on a transom. In surfacing operation, higher rake can hold the water better as it’s being thrown into the air — deflecting it aft and creating more thrust.- Fred Kiekhaefer
Anyone ever try the higher rake angle props on a heavy flat bottom?
Seems like it would be the ticket for high x dimension cleavers and trying to lift the heavy bow of my boat.
Prop guy from Mercury thought the higher rake props have high slip numbers in the midrange but wasn`t sure..
04-23-2017 | 09:28 PM
#5
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From: Slidell, La.
I dont have a high x, but the rake helped keep my bow up with my Outlaw. The Rev4 had more rake vs the B1 stock form. When I tried the Rev 4, it held the bow up well, better than the B1 until I had bblades lab the B1. I had planned on labbing anyway, so after talking to Brett (bblades), he explained the B1 labbed with better results, so I ended up doing that. Had I found a higher pitched Rev4 to try before labbing.. it may have changed the outcome of which prop i ended up with.
04-24-2017 | 11:50 AM
#6
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From: Huntington Beach
I have found that the high rake angle on high X dimension tends to give a lot of tail lift and makes the boat walk a little. And if it has a heavy bow it wont carry the bow it just picks the back up and bow steers at high speeds.
04-24-2017 | 12:29 PM
#7
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From: Grand River, Ohio
2x on Team Archer response.
I did a lot of testing with both the Dragon and GTMM with 5 and 6 blades and high rake. we had the same issue of the high rake lifting the ass end and making her unstable at high speeds over 80. They both likes a little deeper X with less rake. Much more predictable in high speed turns as well.
I did a lot of testing with both the Dragon and GTMM with 5 and 6 blades and high rake. we had the same issue of the high rake lifting the ass end and making her unstable at high speeds over 80. They both likes a little deeper X with less rake. Much more predictable in high speed turns as well.
but you will probably be able to use the same props you have now.
