What are the present options if a builder wants to use a G13 in an airplane? Here's what I'm aware of: 1)Aeromomentum: They use new components and appear to offer a complete range of assistance (buy a complete engine with PSRU and en engine mount, buy each component separately (incl FI and ignition adapted for aviation, different from OEM, etc). Good (if limited) web site, a presence on our forum here, and etc. Many successful airboat installations, fewer flying installations at present. Just Suzukis, US based. G13BB (upright) from new parts with their CNC geared PSRU: $7995, low-profile version (tipped 70 deg) = $9995 2) Airtrikes: Vasili sources his geared PSRUs from the FSU, he is based in Canada. He has many years of fitting Suzukis and other engines to aircraft, but mostly trikes. IMO, the web site is a bit hard to navigate, and the information is not always consistent. He sells used engines, and complete engines with or without PSRUs as wells other components can be purchased separately. Used G13BB (upright) with the SPG3 PSRU and electronics: $7895 (per web site) 3) Raven Rotors/redrives: A long history of fitting Suzukis into aircraft of various types. Their belted PSRU moves the prop hub up, and might make it possible to use a "standard" vertical engine installation in a conventional tractor aircraft, which could save some money by allowing use of the more common and less expensive upright G13. US based. But--have they entirely abandoned the Suzukis to concentrate on Hondas? That's the last thing I heard. Are there others offering assistance with the conversion of Suzuki G13s for aircraft?