Complex sentence: Class B is contested by modified, road based saloon cars with engines of up to 1800cc.Class follows the same rules as Class B, except that it requires engine sizes to be above 1800cc.
Split into simpler sentences: Class B is contested by modified, road based saloon cars with engines of up to 1800cc. Class C follows the same rules as Class B, except that it requires engine sizes to be above 1800cc.