SS/H is 9.5 lbs/factered HP, not 10.5, I is 10.0, J is 11.0. The 440 combo is limited by the carb and head castings a bit more than the 383. The 383 is an overall faster combo, de-factored to around 300HP. The Charger in question is a cool car and looks like a fun ride, hope he has great success with it.