yes,u see I'm looking at santo page and for the 3 cly they have almost every replacement part for their engines and then i'm looking at evolution and they have no many parts for their radials ,,still I like more the radial 7 cly and i'm goin to use the engine of choice win a fokker eindecker proctor I'm building ,the plans recommends the zeidel and with this engine the plane will balance perfectly and will fit perfectly .