Overview of TEXTRON LYCOMING 320 Series Engine Variants
O-320 Series
O-320-Α (150 hp (112 kW) at 2700 rpm) - Compression ratio 7.00:1 - Operates on minimum fuel grade 80/87 AVGAS
O-320-A1A - Base model. Provisions for a controllable-pitch propeller and 25-degree spark advance.
O-320-A1B - Same as A1A with straight riser in oil sump and -32 carburetor.
O-320-A2A - Same as A1A but intended for use with a fixed-pitch propeller.
O-320-A2B - Same as A2A with straight riser in oil sump and -32 carburetor.
O-320-A2C - Same as A2B with retard breaker magnetos.
O-320-A2D - Same as E3D with conical mounts.
O-320-A3A - Same as A1A with 7/16" prop bolts.
O-320-A3B - Same as A3A with straight riser in oil sump and -32 carburetor.
O-320-A3C - Same as A3B with retard breaker magnetos.
O-320-B (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operates on minimum fuel grade 100/130 or 91/96 AVGAS
O-320-B1A - Same as A1A with high compression pistons.
O-320-B1B - Same as B1A with straight riser in oil sump and -32 carburetor.
O-320-B2A - Same as B1A with fixed-pitch propeller provisions.
O-320-B2B - Same as B2A with straight riser in oil sump and -32 carburetor.
O-320-B2C - Same as B2B with retard breaker magnetos.
O-320-B2D - Same as D1D with conical engine mounts and no propeller governor.
O-320-B2E - Same as B2B except that the carburetor is in the same location as the O-320-D models.
O-320-B3A - Same as B1A with 7/16 inch propeller bolts.
O-320-B3B - Same as B1A with 7/16 inch propeller bolts, a straight riser in oil sump, and -32 carburetor.
O-320-B3C - Same as B3B with retard breaker magnetos.
O-320-C (160 hp (150 hp (112 kW) at 2700 rpm) - Compression ratio 7.00:1 - Operates on minimum fuel grade 80/87 AVGAS
O-320-C1A - Low compression version of B1A.
O-320-C1B - Low compression version of B1B.
O-320-C2A - Low compression version of B2A.
O-320-C2B - Low compression version of B2B.
O-320-C2C - Low compression version of B2C.
O-320-C3A - Low compression version of B3A.
O-320-C3B - Low compression version of B3B.
O-320-C3C - Low compression version of B3C.
O-320-D (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operates on minimum fuel grade 100/130 or 91/96 AVGAS
O-320-D1A - Same as B3B with Type 1 dynafocal mounts.
O-320-D1B - Same as D1A with retard breaker magnetos.
O-320-D1C - Same as D2C with provisions for a controllable propeller.
O-320-D1D - Same as the D1A with Slick instead of Bendix magnetos and a horizontal carburetor and induction housing.
O-320-D1F - Same as E1F with high compression pistons.
O-320-D2A - Same as D1A with fixed-pitch propeller provisions and 3/8" attaching bolts.
O-320-D2B - Same as D2A with retard breaker magnetos.
O-320-D2C - Same as D2A except that it is equipped with -1200 series magnetos.
O-320-D2F - Same as E2F with high compression pistons.
O-320-D2G - Same as the D2A except that it is equipped with Slick instead of Bendix magnetos and 7/16" instead of 3/8" propeller flange bolts.
O-320-D2H - Same as the D2G except that it is equipped with a O-320-B sump and intake pipes and carries provisions for AC type fuel pump.
O-320-D2J - Similar to the D2G but with two Slick impulse coupling magnetos and the propeller governor pad, fuel pump and governor pads on the accessory housing all not machined.
O-320-D3G - Same as the D2G with 3/8" propeller attaching bolts.
O-320-E (150 hp (112 kW) at 2700 rpm) - Compression ratio 7.00:1 - Operates on minimum fuel grade 80/87 AVGAS
O-320-E1A - Same as A3B with Type 1 dynafocal mounts.
O-320-E1B - Same as E1A with retard breaker magnetos.
O-320-E1C - Same as E1B.
O-320-E1F - Same as E1C with propeller governor drive on the left front of the crankcase.
O-320-E1J - Same as the E1F with Slick magnetos.
O-320-E2A - Same as E1A but with fixed-pitch propeller, 3/8" attaching bolts and an alternate power rating of 140 hp (104 kW).
O-320-E2B - Same as E2A with retard breaker magnetos.
O-320-E2C - Same as E2A with -1200 series mags and an alternate power rating of 140 hp (104 kW).
O-320-E2D - Similar to E2A with Slick magnetos and O-235 front.
O-320-E2F - Same as E1F with fixed pitch propeller provisions.
O-320-E2G - Same as E2D with O-320-A sump and intake pipes.
O-320-E2H - Same as E2D with S4LN-20 and -21 magnetos.
O-320-E3D - Same as E2D with 3/8" propeller flange bolts.
O-320-E3H - Same as E3D with S4LN-20 and -21 magnetos.
O-320-H (160 hp (119 kW) at 2700 rpm) - Compression ratio 9.00:1 - Operates on minimum fuel grade 100LL AVGAS
O-320-H1AD - Engine with integral accessory section crankcase, front-mounted fuel pump, external mounted oil pump and D4RN-2O21 impulse coupling dual magneto.
O-320-H1BD - Same as H1AD with a D4RN-2200 retard breaker dual magneto.
O-320-H2AD - Same as H1AD with provisions for a fixed-pitch propeller (troublesome engine installed on the 1977 to 1980 Cessna 172N Skyhawk). Due to spalling problems from incorporation of barrel shaped hydraulic lifters instead of mushroom type, multiple service bulletins and airworthiness directives have been issued and modifications implemented to attempt to mitigate its design defects.
O-320-H2BD - Same as the H2AD with a D4RN-2200 retard breaker dual magneto.
O-320-H3AD - Same as the H2AD but with 3/8" propeller flange bolts instead of 7/16".
O-320-H3BD - Same as H3AD with a D4RN-2200 retard breaker dual magneto.
IO-320 Series (Fuel Injection)
IO-320-A (150 hp (112 kW) at 2700 rpm) - Compression ratio 7.00:1 - Operates on minimum fuel grade 80/87 AVGAS
IO-320-A1A - Base model with a Bendix RSA -5AD1 fuel injection system.
IO-320-A2A - Same as A1A with provisions for fixed-pitch propeller.
IO-320-B (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operates on minimum fuel grade 91/96 or 100LL AVGAS
IO-320-B1A - Same as the A1A with the fuel injector offset toward the engine's fore and aft centerline.
IO-320-B1B - Same as the A1A but with an AN fuel pump drive.
IO-320-B1C - Same as the B1A with an adapter for mounting the fuel injector straight to the rear.
IO-320-B1D - Same as the B1C with S-1200 series high altitude magnetos.
IO-320-B1E - Same as the D1C except with a horizontal fuel injector.
IO-320-B2A - Same as the BIA with provision for a fixed-pitch propeller.
IO-320-C/IO-320-D (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operate on minimum fuel grade 91/96 or 100LL AVGAS
IO-320-C1A - Same as the B1B except that it includes features for adding a turbo-supercharger via a Supplemental Type Certificate.
IO-320-C1B - Same as the C1A with a horizontal rear-mounted fuel injector.
IO-320-D1A - Same as the B1D with Type 1 dynafocal mounts, S4LN-1227 and S4LN-1209 magnetos and the fuel injector mounted vertically under the oil sump.
IO-320-D1B - Same as the D1A with the propeller governor drive on the left front of crankcase instead of on the accessory housing.
IO-320-D1C - Same as the D1B with Slick Magnetos.
IO-320-E (150 hp (112 kW) at 2700 rpm) - Compression ratio 7.00:1 - Operates on minimum fuel grade 80/87 AVGAS
IO-320-E1A - Same as E2A with provision for a controllable-pitch propeller.
IO-320-E1B - Same as E1A with Slick 4050 and 4051 magnetos.
IO-320-E2A - Same as A2A with Scintilla S4LN-20 and S4LN-21 magnetos, straight conical mounts and the fuel injector mounted under the oil sump.
IO-320-E2B - Same as E2A with Slick 4050 and 4051 magnetos.
IO-320-F (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operates on minimum fuel grade 91/96 or 100LL AVGAS
IO-320-F1A - Same as the C1A except that it is equipped with a Type 1 (30°) dynafocal mount attachment instead of Type 2 (18°) mount attachment.
LIO-320 Series (Counter-clockwise Engine Rotation)
LIO-320-B (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operates on minimum fuel grade 91/96 or 100LL AVGAS
LIO-320-B1A - Same as B1A except with counter-clockwise engine rotation and reverse rotation of accessories. It uses a modified starter ring gear, crankshaft, cam shaft, accessory housing and oil pump body. This engine is usually paired with an IO-320-B1A on a twin-engined aircraft.
LIO-320-C1A - Same as C1A except with the same changes as the LIO-320-B1A. It has provisions for adding a turbo-supercharger. This engine is usually paired with an IO-320-C1A on a twin-engined aircraft.
AIO-320 Series (Fuel Injection)
AIO-320-A/AIO-320-B/AIO-320-C (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operate on minimum fuel grade 91/96 or 100LL AVGAS
AIO-320-A1A - Same as the IO-320-B1D except that this model permits installation and operation of the engine in the inverted position. The differences include a front-mounted propeller governor, two dry oil sumps, dual external oil scavenge pumps, an oil tank, three options for the position of the fuel injector and a Type 1 dynafocal mount.
AIO-320-A1B - Same as the A1A with one impulse coupling magneto.
AIO-320-A2A - Same as the A1A with provision for a fixed-pitch propeller.
AIO-320-A2B - Same as the A1A except that it has one impulse coupling magneto and intended for use with a fixed-pitch propeller.
AIO-320-B1B - Same as the A1B with a front-mounted fuel injector.
AIO-320-C1B - Same as the B1B but with the fuel injector vertically mounted on bottom of the oil sump in the front position.
AEIO-320 series (Fuel Injection - Aerobatic Aircraft)
AEIO-320-D (160 hp (119 kW) at 2700 rpm) - Compression ratio 8.50:1 - Operates on minimum fuel grade 91/96 or 100LL AVGAS
AEIO-320-D1B - Same as the IO-320-D1B with an inverted oil system kit to allow aerobatic flights.
AEIO-320-D2B - Same as the AEIO-320-D1A without provisions for a propeller governor.
AEIO-320-E (150 hp (112 kW) at 2700 rpm) - Compression ratio 7.00:1 - Operates on minimum fuel grade 80/87 AVGAS
AEIO-320-E1A - Same as the IO-320-E1A with an inverted oil system kit to allow aerobatic flights.
AEIO-320-E1B - Same as the IO-320-E1B with an inverted oil system kit to allow aerobatic flights.
AEIO-320-E2A - Same as the IO-320-E2A with an inverted oil system kit to allow aerobatic flights.
AEIO-320-E2B - Same as the IO-320-E2B with an inverted oil system kit to allow aerobatic flights.
