Great Plains engines are built from Volkswagen auto engines into full and 1/2 VW aircraft engines by a conversion package developed and sold by Great Plains Aircraft Supply Co., Inc., initially of Palatine, Illinois and now of Boys Town, Nebraska. Steve Bennett, the founder, began the firm in 1981 and by 1982 was delivering engines. The firm sells conversion plans, conversion kits, and will build (or rebuild many other manufacturers') VW conversions. An article about the firm and its products can be found in KP2/03. They have extended their development of VW engines by converting to drive from the rear of VW engines and also have worked since 1999 with Valley Engineering so that they now sell Valley cog-belt-driven Propeller Speed Reduction Units (PSRU). In 2001, Great Plains became the sole distributor of the plans for Carr Precision 1/2 VW conversions and also provides kits for the conversions. Great Plains announced in 2005 that the firm was offering liquid-cooled cylinder heads for their engine conversions. This development was carried out in conjunction with Liquid Cooled One, LLC and the firm is now offering liquid-cooled head kits for the 92mm bore Great Plains OL-133 and another version for a 94mm bore engine. The information here has been obtained from the references below and the Great Plains Website. Steve Bennett is also a Contributing Editor on VW conversions for "Custom Planes" magazine. The initial Great Plains VW Type 1 conversions were direct front drive (off the pulley end of the engine). Later, the firm developed the direct rear drive (off the flywheel end of the engine), as described above. The geared engine conversions are all front drive.
O-63 - - {3.622 / 3.071 / 63.3} / {92 / 78 / 1037}
Same bore and stroke as O-127.
Same bore as O-67, O-112, O-133, OL-133.
2cyl; Great Plains/Carr 1/2 VW 1037cc; 35hp@3400rpm; 2001-present; Wt = 87-92#.
VW Type 1; Carbureted engine with single ignition; plans are for either a cut or complete crankcase, but kits are for a complete crankcase only.
KP4/02.
Applications: (US) Hummel Hummel Bird.
O-67 - - {3.622 / 3.228 / 66.5} / {92 / 82 / 1090}
Same bore and stroke as O-133, OL-133.
Same bore as O-63, O-112, O-127.
Same stroke as O-139.
2cyl; Great Plains/Carr 1/2 VW 1090cc; 38hp@3400rpm; 2001-present; Wt = 87-92#.
VW Type 1; Carbureted engine with single ignition; plans are for either a cut or complete crankcase, but kits are for a complete crankcase only.
KP4/02.
Applications: (US) Hummel Hummel Bird.
O-97 - - {3.366 / 2.717 / 96.7} / {85.5 / 69 / 1585}
Same stroke as O-102, O-112, O-117.
4cyl; Great Plains 1600cc; 50hp@3400rpm, 55@3600 (TO); 1982-present; Wt = 159#.
VW Type 1; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (UK) Taylor (John) Monoplane. (US) Evans VP-1 Volksplane; Flaglor Sky Scooter; Monnett Sonerai I; Parker (Calvin) Teenie Two; Pazmany PL-4A; T.E.A.M. V-Max.
O-102 - - {3.465 / 2.717 / 102.4} / {88 / 69 / 1679}
Same stroke as O-97, O-112, O-117.
4cyl; Great Plains 1700cc; 55hp@3400rpm, 57@3600 (TO); 1982-present; Wt = 160#.
VW Type 1; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (UK) Taylor (John) Monoplane. (US) DCS Mini Coupe; Monnett Sonerai I, II.
O-112 - - {3.622 / 2.717 / 112.0} / {92 / 69 / 1835}
Same bore as O-63, O-67, O-92, O-133, OL-133.
Same stroke as O-97, O-102, O-117.
4cyl; Great Plains 1835cc; 60hp@3400rpm, 65@3600 (TO); 1982-present; Wt = 163#.
VW Type 1; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (Australia) Corby Starlet. (UK) Taylor (John) Monoplane. (US) CIRCA Reproductions (7/8-scale Nieuport 11, 12, 17); Evans VP-1 Volksplane; Fisher Avenger V, Youngster V; Monnett Sonerai I, II, II L, II LT; Pober Pixie; Rag Wing Special; Rand Robinson KR-1, KR-2; T.E.A.M. V-Max; Thatcher CX-4; Viking Cygnet SF-2A.
O-117 - - {3.701 / 2.717 / 116.9} / {94 / 69 / 1915}
Same bore as O-139.
Same stroke as O-97, O-102, O-112.
4cyl; Great Plains 1915cc Direct Drive; 65hp@3400rpm, 69@3600 (TO); 1982-present; Wt = 168#.
VW Type 1; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (US) Great Plains Easy Eagle; Monnett Sonerai I, II.
4cyl; Great Plains 1915cc Geared Drive; 65hp@3400rpm, 85@4200 (TO); 1982-present; Wt = 185#.
VW Type 1; Carbureted engine with options for single or dual ignition, geared to options of 0.5, 0.625, 0.775 by Valley Engineering PSRU.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (US) CIRCA Reproductions (7/8-scale Nieuport 11, 12, 17); Evans VP-1 Volksplane; Pober Pixie; Preceptor Ultra Pup; Viking Cygnet SF-2A.
O-127 - - {3.622 / 3.071 / 126.6} / {92 / 78 / 2074}
Same bore and stroke as O-63.
Same bore as O-67, O-112, O-133, OL-133.
4cyl; Great Plains 2074cc; 65hp@3400rpm; 1982-present; Wt = N/A.
VW Type 1; Carbureted engine with options for single or dual ignition.
Applications: (US) Preceptor Ultra Pup.
O-133 - - {3.622 / 3.228 / 133.1} / {92 / 82 / 2180}
Same bore and stroke as O-67, OL-133.
Same bore as O-63, O-112, O-127.
Same stroke as O-139.
4cyl; Great Plains 2180cc Direct Drive; 70hp@3400rpm, 76@3600 (TO); 1983-present; Wt = 168#.
VW Type 1; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (Australia) Corby Starlet. (US) Avid Flyer; Fisher Youngster V; Monnett Sonerai I, II L, II LS, II LT, II LTS; Preceptor Ultra Pup; Rand Robinson KR-1, KR-2, KR-2S; SkyStar KitFox Classic 3, IV; Slipstream Industries Dragonfly; Sonex Ltd. Sonex.
4cyl; Great Plains 2180cc Direct, Rear Drive; 75hp@3400rpm, 80@3600 (TO); 1998-present; Wt = 180#.
VW Type 1; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (US) Monnett Sonerai I, II LTS; Rand Robinson KR-1, KR-2, KR-2S; Slipstream Industries Dragonfly; Viking Cygnet SF-2A; Zenith 601.
4cyl; Great Plains 2180cc Geared Drive; 103hp@4200rpm (TO); 1999-present; Wt = 191#.
VW Type 1; Carbureted engine with options for single or dual ignition, geared to options of 0.5, 0.625, 0.775 by Valley Engineering PSRU.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: (Australia) Corby Starlet. (US) Avid Flyer; Rand Robinson KR-2, KR-2S; SkyStar KitFox Classic 3, IV.
OL-133 - - {3.622 / 3.228 / 133.1} / {92 / 82 / 2180}
Same bore and stroke as O-67, O-133.
Same bore as O-63, O-112, O-127.
Same stroke as O-139.
4cyl; Great Plains 2180cc Liquid Cooled Direct Drive; 100hp@3400rpm (TO); 2005-present; Wt = 180#.
VW Type 1; Carbureted engine with liquid-cooled cylinder heads and options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: None found.
4cyl; Great Plains 2180cc Liquid Cooled Geared Drive; 120hp@4200rpm (TO); 2005-present; Wt = 191#.
VW Type 1; Carbureted engine with liquid-cooled cylinder heads and dual ignition, geared to options of 0.5, 0.625, 0.775 by Valley Engineering PSRU.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: None found.
O-139 - - {3.701 / 3.228 / 138.9} / {94 / 82 / 2276}
Same bore as O-117.
Same stroke as O-67, O-133, OL-133.
4cyl; Great Plains 2300cc; 76hp@3400rpm, 80@3600 (TO); 1983-present; Wt = N/A.
VW Type 1; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03, 4/05.
Applications: None found.
O-144 - - {4.055 / 2.795 / 144.4} / {103 / 71 / 2366}
4cyl; Great Plains 2400cc; 78hp@3400rpm, 85@3600 (TO); 1982-present; Wt = 188#.
VW Type 4; Carbureted engine with options for single or dual ignition.
KP4/00, 4/01, 4/02, 4/03.
Applications: None found.