Prop selection time - 32 Scorpion CC
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Prop selection time - 32 Scorpion CC
Now that the new motors (250 Verado) are on it's time to start looking at new props. The current props are Rev-4 21" with the 1/2 open vent plugs to soften the bite at take-off (the old motors needed it, haven't tried closing the vents with the new motors). Max RPM is 5800-5900 with 1-2 people and 3/4 fuel. The motors are still breaking in and only have 4.5 hours on them so may go up a little, but I doubt 400 RPM that I need.
From the limited test time so far, it looks like I may need props with a little less bow lift and more stern lift. Below 40 mph it likes the motors tucked under. 40-50 it runs best with them trimmed to just neutral with the bottom (4-5 on the trim gauges). At the brief tests so far at full throttle it will take trim up to about 5, maybe a touch past neutral, before it will get upset with waves/wakes (will hold fine in flat water, but that's no fun). The boat wants the tabs (long 380 K-planes) full up now, where before it ran best with them about neutral to the bottom.
Possilbe candidates?
Rev-4 19"
Enertia 3B 19" or 21"
I've run a Bravo-1 22" on the boat with the old motors and it had more stern lift but didn't seem to have the balance of the Rev-4. With the new motors and more weight off the rear (bracket mounted) I think the cg moved aft a little and the Bravo-1 might balance better, but alas they don't make a 20".
We do have the motors set lower than the old ones, as the old ones had trouble holding water pressure when the boat heeled with strong cross winds (even with the tabs holding it level).
What do the prop masters suggest? Anyone take trades?
-Greg
From the limited test time so far, it looks like I may need props with a little less bow lift and more stern lift. Below 40 mph it likes the motors tucked under. 40-50 it runs best with them trimmed to just neutral with the bottom (4-5 on the trim gauges). At the brief tests so far at full throttle it will take trim up to about 5, maybe a touch past neutral, before it will get upset with waves/wakes (will hold fine in flat water, but that's no fun). The boat wants the tabs (long 380 K-planes) full up now, where before it ran best with them about neutral to the bottom.
Possilbe candidates?
Rev-4 19"
Enertia 3B 19" or 21"
I've run a Bravo-1 22" on the boat with the old motors and it had more stern lift but didn't seem to have the balance of the Rev-4. With the new motors and more weight off the rear (bracket mounted) I think the cg moved aft a little and the Bravo-1 might balance better, but alas they don't make a 20".
We do have the motors set lower than the old ones, as the old ones had trouble holding water pressure when the boat heeled with strong cross winds (even with the tabs holding it level).
What do the prop masters suggest? Anyone take trades?
-Greg
#2
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Thanks. I didn't quite make my goal of burning up all the gas in the tanks over the weekend (had to chase down a broken bilge pump connection and a small power steering leak) but I am very happy with them so far.
-g
-g
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Thanks. Several people have told me the Verado's usually pick up quite a bit of RPM once they get to 20-25 hours. I'm wondering if I should wait till spring and see how much they loosen up before I put new props on or not.
-g
-g
#6
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Stick with the Rev 4's. They actually sound like they are doing pretty much what they should. Some fine tuning might be all that is needed.
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Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
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Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]