Hey guys- I picked up a super clean 413! It is a RV motor built 4/71. Came complete top to bottom with only 60K miles or so. Air cleaner says 265 HP. Has the HUGE water pump and exhaust manifolds. This engine gets the "most cast iron" award! I am assuming the torque to be around 450-500 FT Lbs.? Can someone give me a website or two for other specs on the industrial/ motorhome engines. The RB pad says GT 413 and a letter "D". The heads are a 2899943 or 948- can't quite tell on the 3 or 8. I have never heard of these castings. Any help would be great!!