The thrush has an offset outlet. I turned it vertically to help drop the 90* under the frame. With your choice of tip, could look spectacular.

 

That didn't work. Try again.
http://youtu.be/-QTyRh-VhLA

 

So you won't loose any hp or torque? ?

 

No. In theory reduced back pressure would help the engine run more efficiently (more power to the wheels) but on occasion exhaust exiting under the vehicle will exit into a high pressure pocket increasing back pressure but IDK if this ever really happens... TL;DR People do this all the time and it doesn't change horsepower and it sounds the same. Get a dump valve.