I would LOVE to have 400hp out of my 460 Jet... The beauty of your setup is that you ahve the same weight in the back end that I do... But your pushing 75 more HP. Your going to like that A lot!
I have a 20' CVX 20 on a single axle trailer, so it's not uncommon. All depends on the load rating of your tires. My CVX-20 is rated at 2300lbs (aprox) dry so I figure that I'm running close to 3500 lbs wet on the trailer.