Okay, I'll bite:
222 – Introduced in 1980, Lycoming LTS101-650C-2/C-3 donks. Later referred to
unofficially as the 222A
222B – Introduced in 1980, uprated LTS101-750C-1 donks, M/R diameter increased by 2¼ ft
222UT – Introduced in 1983, variant of 222B with skid-gear and increased fuel capacity (~60 gal, as a result of the elimination of the retractable gear, a benefit shared with the 230UT and 430UT)
222SP – Introduced in 1988, a handful of Allison 250-C30G conversions undertaken by Heli-Air
230 – Introduced in 1992, development of 230 with 250-C30Gs, liquid inertia vibration elimination (LIVE) system, new high-inertia rotor blades, optional EAPS, simplified electronic systems, and dual hydraulic/electrical/fuel systems; offered with retractable gear or skids (230UT)
430 – Introduced in 1996, featured the four-blade model 680 rotor system, stretched fuselage and Allison 250-C40s; offered with retractable gear or skids (430UT)
The 222SP and 230 were reported to be 5 kts quicker than the 222B in the cruise, with the skid-equipped UT models losing 5-10 kts.
Though most of the 222SP conversions were the underpowered A models,
AFAIK at least one EMS aircraft still flying was a 222B conversion.
I
believe that the skid conversions were factory-options only, but can’t give you a definitive answer on that.
I/C