TRS to SSM3 HP change
 

What is the HP draw TRS to Speedmaster3? clearly a 3 takes more to spin, curious as to what that may be??

There's no perfect answer. We used to say 6%-10% HP loss depending on the drive.
Some say almost twice as much loss for the dual vet shafts in SSM's.
Same engine set up on same prop shaft dyno with each drive is the only perfect answer.

Brett

Gotcha, thx just doing some numbers old boat vs new...

I personally wouldn't worry about it. I'd go with the stronger drive, and that is the SSM.

Not changing, I have SSM on new boat I’m trying to conjure engines and speeds