The CG13 as standard would be a group N car (means standard trim) so you cant do that much to it, standard engine, box, all trim inside. So you are right with that power difference!
so, I'd know the differences between the engine of a K11 with gr.a specs and the engine of a K11 kit car.
I see the photos on abby's 3d, that car kit has a HUGE airbox , and here you talk about 8 injectors, sequential gearbox etc etc... edit
I red the specs in the kit car 3d... very impressive