Can anyone tell me what the total horsepower is on a 2004 Sierra with flowmaster exhaust added. It it the 5.3L.

 

Well, its 295 stock. So the the amount you got from the exhaust is questionable depending on how much back pressure it is regulating. I would say that you might be at like 305-310. Thats as good of a guess as your gonna get without dynoing it