Cooler intake manifold

Cool air going into the engine will surely make a difference. A good, sealed hood scoop, or fresh air from the grill area is good but you will probably have to make your own set-up as far as that goes. K&N air filters are also very good but expensive at first, but worth it in the long run. Ducting cooler outside air to the carb should be a pretty well sealed set-up. (Under hood hot air, not nearly as good) I have heard of someone making a valley pan for a small block Mopar (non Magnum) from a 383- intake valley pan cut down to fit. Utawsome Performance makes one for Magnum engines. It bolts down to the 3 bosses that hold the roller lifter retainer in place. (I have used one on my Dakota) Keeping hot oil from splashing on the bottom of the intake is a help & like Brooks James said, a cool can for the fuel is also a great idea. Keeping your air & fuel cooler is always better, look at what adding Nitrous Oxide does when it cools the fuel being burned.