Any decent BB 45 would do. I hear that the Evo engines work real well. I do not have one. A TT 46 Pro would do it nice. good engine at a good price. Before I spent the bucks on an OS I would buy an Irvine. I have 2 53's and like them. I would reccomend them highly. I would look at my pocketbook. If it is kinda lean then I would buy the TT or the Evo engine. If I had the money I would go Irvine. This is my opinions. I wish you well on your kit.

Mark Shuman