Pimp my Train

[Steamdemon]

I just finished a test run of my modded FS GR940 044 which is fitted with a A3 Gresley engine (top speed 111mph). I just need to find a better engine for the RENFE 305 Hydraulic shunter 550hp. I already fitted it with an airhorn (cause airhorns are threatening, enough to tell idiotic people on the line to GET THE HELL OUT OF MY WAY!!!)

I would like an engine like the ones in the UP Diesels so, what would be best?