Lycoming WWII Engines

Lycoming WWII Production Engines
Compiled by Kimble D. McCutcheon from Material Provided by Scott Rodriguez
Published 11 Oct 2018

Lycoming's first aircraft engine, the 9-cylinder R-645, was rated at 185 hp and received Approved Type Certificate No. 27 on 30 Sep 1929. An enlarged R-680 received Approved Type Certificate No. 42 on 4 Feb 1930 and was rated at 215 hp. A 7-cylinder R-530 with a 210 hp normal rating followed on 23 Oct 1937. Lycoming's first horizontally-opposed engine, the 4-cylinder, 50 hp O-145, received its Approved Type Certificate on 13 Jun 1938. Below are images and specifications of the Lycoming engines in production during 1943.

Horizontally-Opposed Engines
	Takeoff Rating			Propeller			Overall Dimensions			Installation
Model	HP	RPM	Fuel Octane	Gear Ratio	Shaft	Weight (lb)	Length	Height	Width	Spec	Ins Dwg	Notes	Images
O-145-A2	55	2,300	73	1:1	6-F	163.11	24.62	20.59	29.56	1026	45003	2
O-145-A3	55	2,300	73	1:1	6-F	165.34	24.62	20.59	29.56	1082	45002	3	LF
O-145-A4	55	2,300	73	1:1	6-F	200.36	26.00	23.00	29.56	1083	45012	4
O-145-B2	65	2,550	73	1:1	6-F	163.40	24.62	20.59	29.56	1035	45003	2
O-145-B3	65	2,550	73	1:1	6-F	165.63	24.62	22.59	29.56	1084	45002	3
O-145-B4	65	2,550	73	1:1	6-F	200.50	26.00	23.00	29.56	1085	45012	4
O-145-C2	75	3,100	73	1:1	6-F	163.40	24.62	20.59	29.56	1028	45003	2
O-145-C3	75	3,100	73	1:1	6-F	165.63	24.62	22.59	29.56	1086	45002	3
O-145-C4	75	3,100	73	1:1	6-F	200.50	26.00	23.00	29.56	1087	45012	4
GO-145-C2	75	3,200	73	27:17	6-F	196.39	29.31	20.59	29.56	1045	45005	2
GO-145-C3	75	3,200	73	27:17	6-F	198.62	29.31	22.59	29.56	1088	45001	3	LF
GO-145-C4	75	3,200	73	27:17	6-F	233.49	30.69	23.00	29.56	1089	45013	4	A
O-235	100	2,550	73	1:1	6-F	239.00	30.09	25.19	32.32	1080-B	60210	5	LF, A
O-235-A	100	2,550	73	1:1	6-F	268.30	31.54	25.20	32.32	1081-A	60211	6	A
O-290-A	125	2,450	73	1:1	8-F	277.30	31.64	25.48	32.32	1079-D	60208	7	A
O-290-B	125	2,600	73	1:1	8-F	245.79	30.09	26.64	32.32	2011	60215	8
O-290-C	125	2,600	73	1:1	8-F	238.01	30.09	26.64	32.32	2012-C	60216	9	LF, A
O-290-D	130	2,800	80	1:1	8-F	257.00	30.09	22.81	32.24	2069	63723	9	LF, A
O-350	150	2,500	73	1:1	#20	348.52	45.48	28.04	32.32	1076-D	65214	5	LF, A
O-350-A	150	2,500	73	1:1	#20	372.99	45.48	26.54	32.32	1077	65201	6	A
O-435-A	175	2,300	73	1:1	#20	384.00	46.21	28.04	32.32	1075-C	65201	7	A
O-435-B	225	3,000	100	1:1	#20	364.66	45.11	29.61	32.32	2016	65221	11	LF, A
O-435-C	185	2,450	73	1:1	#20	352.15	45.48	28.04	32.32	2010-D	65218	10	LF
O-435-T	163	2,800	73	1:1		755.00	48.07	32.17	35.62	1092-B	65209		R
GO-435	210	3,000	73	120:77	#20	394.13	47.70	29.61	32.32	2015	65220	10	LF
GO-435-B	220	3,000	100	120:77	#20	401.10	47.70	29.61	32.32	2014	65219	11	LF
Abbreviations:		6-F = 6-Bolt Flange; 8-F = 8-Bolt Flange; SAE #20 = SAE #20 Spline
Notes:	1. All engines were equipped with a single SAE tachometer drive.
	2. Fuel pump drive, radio shielding and mixture control were available as options.
	3. Fuel pump drive, starter drive, generator drive, radio shielding and mixture control were available as options.
	4. Equipped with Delco Remy starter and generator. Fuel pump drive, radio shielding and mixture control optional.
	5. Equipped with starter and generator drive. Dual tachometer drive, fuel pump drive, radio shielding and priming system optional.
	6. Equipped with Delco Remy starter and generator. Dual tachometer drive, fuel pump drive, radio shielding and priming system optional.
	7. Equipped with Delco Remy starter and generator. Dual tachometer drive, fuel pump drive, radio shielding, cylinder head cooling baffles and priming system optional.
	8. Equipped with starter and AN generator drive. Dual tachometer drive, fuel pump drive, radio shielding, cylinder head cooling baffles and priming system optional.
	9. Equipped with starter and generator drive. Dual tachometer drive, fuel pump drive, radio shielding, cylinder head cooling baffles and priming system optional.
	10. Equipped with starter drive, generator drive and radio shielding. Fuel pump drive, vacuum pump drive, dual tachometer drive, unshielded ignition and priming system optional.
	11. Equipped with starter drive, AN generator drive and radio shielding. Fuel pump drive, vacuum pump drive, dual tachometer drive, unshielded ignition and priming system optional.

Radial Engines
	Takeoff Rating		Normal Rating				Overall Dimensions		Installation
Model	HP	RPM	HP	RPM	Fuel Octane	Weight (lb)	Length	Diameter	Spec	Ins Dwg	Notes
R-680-B4D	---	---	225	2,100	65	492.00	37.09	43.50	1056	1610-P	2
R-680-D5	260	2,300	245	2,100	80	505.00	37.04	43.50	1009	1610-D	3
R-680-D6	245	2,300	245	2,100	73	505.00	37.04	43.50	1010	1610-D	3
R-680-E1	290	2,300	275	2,200	80	514.00	37.04	43.50	1021	1610-G	3
R-680-E2	280	2,300	265	2,200	73	514.00	37.04	43.50	1022	1610-G	3
R-680-E3	300	2,300	285	2,200	87	514.00	37.04	43.50	1023	1610-G	3
R-680-E3A	300	2,300	285	2,200	87	515.00	37.50	43.50	1047-D	1610-M	3
Notes:	1. All engines were direct drive and equipped with a SAE No. 20 propeller shaft.
	2. Equipped with dual tachometer drive, priming system and Cuno oil filter. Fuel pump drive, generator drive, vacuum pump drive and radio shielding were available as options.
	3. Equipped with single tachometer drive, priming system, manual hydraulic propeller control unit, cylinder and head cooling baffles and Cuno oil filter. Fuel pump drive, generator drive, vacuum pump drive, dual tachometer drive, radio shielding and constant speed propeller governor drive were available as options.

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