Prop size for converted 1/8 scale hydro

[PJBJ]

I have converted a wooden Dumas 1/8 scale hydro (solid shaft) from 15 cc to a Scorpion HK4035 800Kv motor. Using 2 4S 35-70 discharge batteries (8S) which fit in the nose requires me to put a lot of lead in the tail to get the boat balanced. I have a 240 Amp ESC. I have 2 props both 1.4 pitch: 55 & 65 mm diameter. I started with the 55 mm and the boat went nose down. I then changed 2 things: added weight in the back and changed to the 65 mm prop. The boat still went nose down. I added more weight and finally it came out of the hole. The water was pretty rough and after 3 rounds I brought her back in. I then discovered a lot of water in the motor/ESC compartment. After drying the boat the ESC did not work any more. Now I ordered a new (water resistant) ESC and I am thinking of getting a 60 mm prop. I could use some advice on this. Thanks.

[boredom.is.me]

Nose down? It's common for hyrdos to dive if you don't gun it out the gate. I can sail my Pickle underwater if I want to. I can't help with the prop selection though.

[Brushless55]

What is your strut depth and angle ?

[PJBJ]

It is a solid shaft with no possibilities to adjust.

[PJBJ]

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