Engine manufactors
Here are some engine manufactors, that I could find, if anybody has interest, google it:
Austro engine GmbH
Centurion Aircraft Engines AG
Deltahawk
Wilksch Airmotive
Diesel Air Limited
Powerplant Developers Limited
Teledyne Continental Motors
SMA Safran Group
Zoche
Raptor Turbo Diesel
ECO Motors
Costruzioni Motori Diesel of Atella, Italy
BRD SrL of Italy
Developments GmbH and RED Aircraft GmbH in Adenau, Germany
and, fo course Gemini