Craig best to contact guys with fast gun Graf Spees already built and get their feedback on the performance from their engine,pump,battery setup..then decide which you think will work best for you.
Craig here's a thought. You could run Graf Spee on an ESC like JAY'S got. One ESC for one large motor on a dual output shaft should give you the speed control you need.
Oye CAPTN SPARROW... yes I have heard of you....btw... lol... anyways..I have decided to build Graf Spee for Combat and that means cutting out that gorgeous hull..It will be built for CWC-X . That means a Torp system on the broadside hee hee hee.. I will be exploring the various setups and decide on the best one for me. Can't wait though. I been itching to command a Graf Spee since I started the hobby 20 years ago. Sooooo here we go. I like to think of these ships as Raptors.
What Curt and I are prepping is a single half unit spurt cannon. It will have five shots of five. I want to place it in the stern, Curt will go with a bow mount.
I may go with a sidemount TORP cannon. I will be checking out the BDE torp system for their small ships like destroyers and see if I Can make and mount a similiar system. If their littel skinny destroyers can do it Graf Spee would be a good platform. I may be able to mount the cylinder with teh cannon on top through the Torp location on the aft quarterdeck. I need to get the measurements of thier system and see if I have room for back there. I would probably have to mount a counter weight opposite it's side. Or I may mount it directy aft. That would be quite nasty considering how low the quarterdeck torps are back there. Still a Broadside deep down angle would be nastier. The main issue back there is the barrel being exposed. I may have to shorten it considerably or mount it closer to the center keel of the aft compartment so that I can maintain a 3 inch length but have less exposed. There 's a bit of logistics there. Anothe option would be to mount it from the main deck amidships or behind the rear aft turret. Some options to look at. For now though a torp as a cannon modified as spurt bow or stern will work.
Well maybe in the IRCWCC or MWC I think. For CWCS your half unit is 25 rounds. 5 shots for 5 rds per shot.
I am leaning very heavily towards the BC one motor dual output drive shaft for the Graf Spee. Like Bismarck easy to wire and set up, easy to adjust speed or swap motors out and gear pinion. The cramped area in the aft section makes using this setup more logical.