Drop in Gas to FE Conversion

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Looks Great! Finish it off with an incorporated ESC mount plate and you just knocked out two of the "swappable power plant" components. Only thing left would be the battery(s)/gas tank. Not bad for 4 screws!

I wonder how far off the prop would be going from a zenoah to one of these FE setups. I'm wondering if there is a KV/bat setup that would get close to the prop used on say a stock zenoah? Or would it be way off?
Looks great Tyler and great suggestion Drew.
Now if someone can come up with a RTR prototype and document here on the forum that would be awesome.
Sign me up for the first production combination package. I think it will be a big hit...

Thanks guys,

Marty
 
That is a cool design. Great looking, lightweight and serviceable. Having bent a lot of materials, I can suggest that you try 6061-T6 aluminum or stainless. The stainless would take a slightly sharper corner bend. 6061-t6 would require about a 1/8" inside radius to prevent cracking. While aluminum can be annealed, I wouldn't do it. Just don't bend it over a sharp corner. Avoid 7075-T6 aluminum. While it is stronger in many applications, it does not like sharp bends. Gentle bends, like in rigger fins, etc are OK, but stress cracks will form if you try to bend it to a square corner. Good luck.
 
Zenoah's peak power is around 16,000 rpm. On 8S that would need a KV of around 500. You would be better off running a smaller prop with a higher KV motor. Something with a KV of 900 to 1000 with a 55 to 58 mm prop should be better. It would run around double the Zenoah rpm and give higher performance. A modified Zenoah has a shaft power of around 4800 watts. On 8S that would need an input current of about 180 amps at 80% motor + ESC efficiency.

Lohring Miller
(Tyler, please check my math.)
 
Lohring,

I usually add 15% or so for voltage sag under load for calculating kv or use 3.7v/cell as as an aggressive under load voltage. Because there are so many motor options in this size range the decision comes down to what props the hull likes. If you go to a higher kv, high rpm and small prop you have to be careful of the lift characteristics. Small props at high RPM on big big boats tend to lift more than they push leading to unwanted tail hopping and bad behavior. For gas conversions or open class boats I usually shoot for a 18-20kRPM loaded range, run a slightly smaller or lower pitch prop compared to a gas motor and adjust from there. That usually results in a very competitive and consistent running boat that hopefully not taxing the power system.

A Castle 2028 with an XLX2 on 8S is a fantastic low cost, reliable, competitive gas conversion setup. 5-7k watts is about right depending on the hull and speeds. If you run 6000-9000mah cells a 1P setup is fine, or run a 2P setup with 8000-10k mAh and have some reserve for extra laps.
 
First prototype fits nice. It’s a little thin in stainless 304 but everything lines up nicely. That’s a 60mm Lehner 3080 for size reference.
 

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