A few years ago my wife brought me this R/C boat for Christmas.

It started life with a geared 540 brush motor with a 40mm x 1.4 pitch prop running on 7.2 volt NiCad pack.

It was slow!!!

So I was talked into changing over to brushless motor direct drive.

I had no experience with these beasts.

So in for a penny in for a pound.

Added a 3639-1100kv 800

watts motor, 5800mah 3S 25C Lipo battery and a 60A car ESC.

The speed increase was amazing and the run time jumped from 10 minutes to about 45 minutes.

Motor ran just warm(no water cooling) and the car ESC (code HK-60A).was the same.

After a few trim changes to the prop angle and the balance point of the boat it ran great!!!

So next I added some Trim Tabs from Hobbyking(code HK-516B12).

Next I changed the 3S Battery to 4S 5600mah 60C.

The motor specs. only rate it at 3S.

After a 45 minute hard run the motor was again only warm.

Speed increase was great, another 4000rpm.

I later found a D3548/4 1100kv 910watt motor was cheaper and was rated for 4S.

Next I changed out the 3639-1100 kv to a 3648-1450kv 1600 watt motor.

Straight bolt in but longer in the body.

Also changed the ESC to 100A car (code HK-100A), this was not required but I require it for my grandson's boat.

I started with the 3S battery and wholly hell it moves!!!

Yes I tried in on 4S it stands on the prop in a straight line, but, very much a handle full.

In windy conditions it's off the throttle as it will go skywards!!!

It's like a Morris 850 with the power of a Ferrari.

I am still running a 40mm x 1.4 pitch prop, but, changed to an alloy one.

This weekend testing a 3 bladed 37mm x 1.4 pitch prop on the beast.

I ran this prop on my grandson's boat and got a bit for an increase in speed.