I've been working on this engine for quite some time. it is a bit hard to print since the tolerances need to be quite tight. it can be a little hard to break free so have some pasient and a well-tuned machine will help. it can be printed in just under 2 hours!

you will need to print this at a 0.2mm layer hight or lower and at about 30% infil. it is necersary to print with 2 layer raft. 

when printed try lubricating it with vegtable oil before breaking it free. after words put on a lego flywheel and use the compressor on the fly wheel to get it up to speed. this will smothen the engine.

i have only tried to print this on my own printer a ender 3 v2 and my fiend witch also have a ender 3 and i got it to work let me know your experiance.