Guys... First... this hull is NOT gel-coated... that's white paint. Very heavily laid on, white paint.
As for speeds... I did some bench testing of the motors this weekend and found some interesting info.
The testing was done with the following setup:
Battery: 4S1P ThunderPower 45C 5000mah pack
ESC: Castle Hydro 240
Timing: 0
Load: 6x3.5" Plastic/Carbon Airplane Prop.
Under this test setup, the motor actually registers 1885KV, and a little over 31,000 RPM unloaded. With the load (airplane prop), the motor dropped to 1703KV, just shy of 27,000RPM, pulled 35.55Amps, and the output was 562 Watts.
For comparison, the Geico motor registers 1460KV and 24,100RPM unloaded, and 1399KV, 22,500RPM, 18.84Amps, and 304Watts with the SAME load.
What this tells us is that the price for the additional KV is torque, so you will NOT be able to turn the same large props. It's more like the UL-1 motor, where it climbs in WATTS quickly as you add load, so you need to turn a smaller prop, with less pitch.
This actually puts the Stiletto setup more inline with the Nitro equivalent, so working with props more similiar in size to what they would use is in order. I tried an X440/3, pitched up slightly, and backcut about .030"... slightly cupped as well. Motor temps were very reasonable (around 108), so it can handle more, but I will increment it up slowly, because my race props for my BJ motor get the motor temps up to dangerous levels and overheat the wire leads. Speeds really aren't appreciably faster either. Just adding load to the motor.
SO, play around with some of the smaller props and see what you come up with. I'm thinking something in the 40-42mm range will be a good place to start, though the 37mm 3-blades might be workable as well.
As for setup. Set the stub shaft centerline about 1/8"-3/16" above the sponson bottoms, neutral or just SLIGHTLY up angle (aft higher than front to lift the nose), and start from there. I prefer it to be dead neutral to start, so as not to have the prop height change as the unit steers. Mine seems to work best with the 4400mah or 5000 mah pack, mounted all the way forward, and I also added 1oz of lead to the nose. That's the setup in the video posted in my Race Prep thread, and the boat is certainly breaking 40mph there (I'm estimating more like 45 or so)
SLOW the steering down, lower the throw as well. You don't need much to get this to turn. Then learn to balance the throttle.
Hopefully this gives you a good place to start from. Let me know how it goes.
Darin E. Jordan - Renton, WA
"Self-proclaimed skill-less leader in the hobby."
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