MM & an X645

[Eodman]

Evening Fellas - quick question I built a MM with a 9xl and an Etti 150 ... is an Octura X645 to much prop for this build? Power will be 2s2p!

[Apples1]

sounds ok ,i wouldnt think that you would pull more than 150 amps with that set up.

[line6]

I assume your running two 2s packs in series for 14.8 volt and not two in parallel for 7.4. I would not start with that prop. Try a 442 and go up if you can.

[detox]

two 2s packs in series is 4s1p

[jingalls007]

Don't start with that prop. I run a similar setup in my sprint cat, same hull basically and I run a Hydra 240 in mine but that heats up and so does my NEU 1515 with the X645 and the boat was WAY TOO fast and uncontrollable with that prop anyway. I had really great luck with the 440/3. Speeds lower 50's and all temps were in the 100-115 range. I started with the M440, then the X637, and finally landed on the X440/3. Start small, check temps, work your way up. Oh and I run 4s2p.

[D. Newland]

I did some testing yesterday with a 32" rigger. 9XL Nemesis, 4S1P 5000 pack of Poly RC's and props anywhere from an X645 to an X448 (X450 that was shaved down a few mm's). No problem running 2 minutes with a Castle 120. After checking amp-draw, I could have run 2 min 30 seconds no problem, but not longer.

If your boat is set up well, it will boil down to how much runtime you want Vs speed.

[Fluid]

A rigger will always be able to run larger props than a cat can, so there is little help there. However if the OP will be running 2S2P like he says he is, then the x645 may not be enough prop!


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[jingalls007]

Evening Fellas - quick question I built a MM with a 9xl and an Etti 150 ... is an Octura X645 to much prop for this build? Power will be 2s2p!

Here's a few pics of my sprint cat (basically the same hull as the MM) at the lake a few days ago running with a X440/3, CG at 9.5" up from the transom. I hope it's ok to post this here.

[NorthernBoater]

Evening Fellas - quick question I built a MM with a 9xl and an Etti 150 ... is an Octura X645 to much prop for this build? Power will be 2s2p!

What kind of speeds are you trying to get. A 9XL on 2s2p may have hard time pushing it above 30 mph with an x645.

[line6]

What kind of speeds are you trying to get. A 9XL on 2s2p may have hard time pushing it above 30 mph with an x645.

I think he meant 4s1p