How often is hp the limiting factor for your 2388's? For us HP is ususaly the limiting factor. A 2188 has more in common with the early 2388's biggest differance is 20 hp, 3spd rotor gearbox and hyd drive rotary screen. What year are your 2388's? 2388's went through many changes throughtout their production. 1688' are basically the same mechanically as a 2188, cab electrical and hyd are the main differances.