Hi Rocco,

It's hard to say what the ampdraw will be, this depends on the boat set-up and propsize.

On our seven cell boats with surface piercing prop (36 0r 37,5K), the average ampdraw of the 8,4V 600 Race is 25 A with a 7-8 minute runtime.

As your boat has subsurface drive, be careful with a 37mm prop, in my experience it's too large and will fry the motor, no matter if it's a 540 or a 600 motor, check the temperature every two minutes, minimal!

If nothing gets too hot, run the boat with a full battery, flat out until the speed drops, measure the runtime.

Using the formula: 60 x battery capacity in A, devided by the runtime in minutes, you'll know the average ampdraw of your boat in that set-up.

If you take a look at the Graupner website (www.graupner.de) you can find data on all motors.

You can find a lot of info on how to make this hull really fast by going to www.rc-raceboats.de and use the search function ( "Suche" ) on "Trimmung", author: M3rl1n.
You'll find a long thread with a number of photos, showing how to go about it.
I added a few I have on my harddrive.

Regards, Jan.