The Lightning XS kit has a redesigned forward fuselage structure that gives the builder the option to choose engines up to 160 hp. Taller landing gear for bigger props, bigger brakes, and 20 gallon fuel tanks are among some of the features of this new kit. It contains much of the same stuff as the classic but is only firewall aft. Then you choose from a list of firewall forward packages we offer to go with it. These include Lycoming type engines O233-O320, 115 hp to 160 hp, UL Power UL350-UL390is, 130 hp to 160 hp engine or Jabiru 3300.  If you have a different engine in mind then you can save the money on the firewall forward and just buy what you need.