Mods for top speed!!!

[RICKEBUENO89]

Hello everyone. After 3 years with my Blackjack 24 on the shelf, I decided to modify it to get a better performance.
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The first modification was the installation of a 100A ESC (the original was 30A).
Right after that I installed another water collector in the rear and added a mini 6V water pump connected directly to the receiver.
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With the original 2200KV motor and 4000mAh 40C battery I didn't notice much speed increase.

I would like to know if with the original engine and a new propeller I will have a higher speed or if I change the original engine for a 3250KV and a new propeller I will have the highest speed of the set.

Below I list the photos of the propellers with especifications:
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I would like help from the professionals. Wich motor + prop should I choose running a 4000mAh 40C 3S lipo batt, for a top spees setup?

I thank you for your help.

[koen]

hi Rick
Go for a leopard or an SSS motor ( 3650 or 3674) go not overboard with kv.s because you can only spin small props ,with lower kv you can go bigger with props
prop wise go for Prather or ABC props (need to sharpend and balanced if needed how you can find it at youtube)

[fweasel]

It's been awhile, but I believe my Blackjack 24 ran about 35mph with a 2000kV 3910 motor and a balanced and sharpened metal prop from the Blackjack29 V3 (close to an Octura M442). I needed a modified motor mount to gain additional clearance at the stuffing tube so that I could run a proper stainless steel collet. I also ran a modified rear strut to correct the wear problem caused by no bearing in the stock setup. My setup did run warm, but it was manageable with just enlarging the pickup in the rudder and drilling out the inner diameter of some offending fittings. Your second pickup will definitely flow more water, at the cost of increased drag. I ran a similar setup in my Shockwave26 with an Octura x440/3 prop. That boat did 43mph on 3S. If you were looking for all out speed, I would probably start with that sized motor and prop.

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[RICKEBUENO89]

Thanks koen and fweasel. You're great, dude. Ill go the leopard setup then. Cheers

[denboy01]

As a percentage, how much performance is lost by extra drag from another water pickup?

[Bp9145]

As a percentage, how much performance is lost by extra drag from another water pickup?

I really couldn't put a percentage number when I've added a water cooling tube on my Motley Crew just like the way you have it. What I did was ran it without the tube in the water and then ran it with it in the water. I used a Garmin forerunner 201 to see if there was a big drop in speed and it didn't. The difference was maybe +/- 1mph-3mph. It was so long ago but, if I remember correctly it even ran faster with the cooling tube in the water. I know in theory it should add some drag and I do believe that. Perhaps, it could affect handling but, speed wise it was negligible and I was only interested the difference in speed and not handling. Also, my test might not have been perfect because water conditions varied and I only tried it for just that day. I should have tried it more on different days and different water conditions. Also, it might make a significant difference on different boat hulls or boat designs. For my Motley Crew, the difference was very small for me to be concerned. You'll just have to test it on your own with that boat.

[fweasel]

The loss is moot if you are in need of extra cooling.