Dont do it. I'm running an EVX2 Marine in a 40" Admiral NQD with 2 8.4v mimhs. I'm running Graupner 600's now but they get way hot so im going to get Kershaw 700's in a lower rpm per volt. 16.8 is plenty of juice to run on, just buy better motors or upgrade your props. The EVX's can handle up to 180 amps.......thats a bunch.......a strong 700 motor only pulls about 30 amps. Dont fry your expensive ESC. By the way, what knid of boat are you running..................a Villain?