They used to say one is better than the other but personally I like the non hemi more. I don't think there is enough of a difference performance wise that should lead you to one motor or the other. Just get whatever is in stock and you should be fine. Just my opinion. I have 100% confidence that I can win with a hemi or non hemi at my local track. Get a motor and focus on CHASSIS, TIRES, TIRES, and one more thing...TIRES