Water not circulating through cooling system.

[Peter A]

You can have long run times, but....you have to set the boat up for it. You will not run at the same high speeds, realistically you will be at 60-70 kph. It will take lower kv and bigger props for efficiency.

In the past I ran an Osprey (42" hull) set up for offshore endurance. The setup was TP 4070 440kv, SK 130HV esc, prop Prather 245 detoungued, 12s (2x 6s) 20,000 mah batteries (5 kg). It would run at 65-70 kph for 20 mins at full throttle. This setup did not have temp issues.
The extra weight of the batteries had no impact on top speed, however they do make the hull heavier, obviously, and so that has an effect on the handling, but can also settle the hull well in rougher water.

I am currently building a 43"cigarette hull with a SSS 4092 1100 kv motor setup to run on 6s. Theoretically I should be able to get 15+ minute runtimes on a single 6s 20AH battery. We shall see in due course. I expect the run speed to be in the 60-70 kph range to do that, but that is still a respectable scale speed and it should handle 6-12"waves no issue.

[Bird_dog92]

If you can't tell I'm very new to RC boats. But what would you suggest I do to make use of my 11300mah battery? Or do you think its safe to use in my stock boat and just not run at full throttle all the time? I really like how the boat handles with the extra weight. I can actually run full throttle without it flipping itself. I'm not sure if a bigger prop will fit and clear the rudder. But hot racing does make a 63mm pitch prop I think. But I'm honestly not sure what that even means. That cigarette you're building sounds awesome. I wish I they would make RC boats based off of real boats like they do with cars and trucks.

[Peter A]

The best option would be to change the motor. Either a Leopard 3674 1400kv, or a SSS 3674 1500kv. You are running 6s right? You have more opportunity to play with more different props then to find what works best.