We have a plate system with a 150 shot installed but havent sprayed yet , we used it on our old engine, havent realy needed it with new eng, if we run mod class we can spray with the cut tires, we run 3.90x2 to 1 gearing just under 8 t 1 in high gear , you may be right the engine cant pull the extra traction & weight with current set up , my torque is good up to 6k 550lbs than realy dumps by 7k 470lbs on paper ,