If you want an engine that kicks , a sh.21 6 port. Hobby People sell them for $229 , but Dinbal has an Ebay store and sells them for $169. I`ve raced against RBs , v-specs ,ofna .21 race , o.s , and some others. The SH has great all around power , every track I`ve been to everyone comes to my pit and wants to see what I`m running. You won`t go wrong with it.