For the 2 inch model you can choose a 5.5 hp Honda with a Wetseal Banjo pump.For the 3 inch model you can choose either a 6.5 hp Honda or a 13 hp electric start Honda, both come with the Wetseal Banjo pump.The 6.5 hp model displaces 256 gpm versus 368 gpm with the 13 hp model and these numbers were our actual test results.All kits come on a powder coated frame that bolts to the existing Chembine, and they have an easy oil drain cut out and additional mounting feet. Both these kits include a 3-way valve that gives you the flexibility to induct or for even quicker fill times pump from the Chembine tank to fill your sprayer.