Adapted from André Schilling's model (https://grabcad.com/library/evolution-engine-1) I cleaned the files up and broke them up into printable pieces. The model is scaled so that the completed engine is about 4" tall, but I recomend scaling 150% - it turns out way better. It also has enough detail to print at well over 200% scale if your printer is big enough. (Picture shown is scaled 150%)
Good luck!
The backs of parts are marked with which side of the engine they go on, (L)eft and (R)ight as well as (F)ront and (B)ack.
Good luck!