Custom engines

Last night I took 2 different engines, 2014 2.0L Ecoboost and a 2015 2.0L TDI biTurbo and turned 2 dyno graphs into 1 dyno graph as if they were connected with matching redline. 6k gas & 4k diesel. 450 Hp & 625 ft/lb. All it took was paper, pen, 2 pictures, and a calculator. I like to design custom engines, I have another completely different design that is a slow process going into a 3D model, starting with clean used cardboard due to limited material & so far no money going into it.

does anyone else have a hobby of designing custom engines or designs engines for a living?