Up to four sets can be worked in multiple to form a 12-car set, although platforms are only capable of handling 6-car trains. The units have a maximum speed of 90 mph, and can complete the 41 mile journey between Glasgow Central and Ayr in around 52 minutes. Since the introduction of the Class 334 units onto the Ayrshire Coast route, most 318s have been found working alongside the 334 fleet.