Which air gap manifold?

Theres actually 3 performer intakes: the performer 318-360,which has the smaller 318 ports,the performer rpm which is for the 340-360 ports,and of coarse the best dual plane intake on the market the performer rpm "air gap"...if you live in a cold climate and drive your car on a regular basis in the cold months i'd suggest the performer rpm,it'll do a better job of help to warming the carb up,the air gap is basically designed to keep heat away from the carb,which makes it a better racing/performing intake....