Subaru EA engine

Summary

The Subaru EA engine is a series of automobile internal combustion engines manufactured by Subaru, a division of Fuji Heavy Industries. All EA series engines are of a flat-4 design, and have always been water cooled.

Subaru EA engine
Overview
ManufacturerSubaru
Production1966–1994
Layout
Configurationflat-four petrol engine
ValvetrainOHV/SOHC
Combustion
Fuel typePetrol/gasoline
Cooling systemwater
Chronology
SuccessorSubaru EJ engine

Design and history edit

Prior to 1966, Subaru was known for producing kei cars in Japan; for their first four-passenger model, the firm developed an air-cooled boxer engine for a prototype of the Subaru 1500 in 1960, but Fuji Heavy Industries was unable to continue development due to a shortage of funding. A new prototype front-wheel-drive car was built with a 923 cc (56 in3) water-cooled boxer engine, which became the basis for the Subaru 1000 and the EA-52 boxer engine. The car began sales to the public starting in 1966.[1]

The EA series engines have aluminum heads with aluminum blocks. Each cylinder has two valves, one for exhaust and one for intake. They came in either an OHV pushrod or SOHC configuration.

Subaru produced the EA series from 1966 to 1994, and were found in the Subaru FF-1 Star, the Subaru Leone, the Subaru Brat (Brumby), the Subaru Loyale, the Subaru Omega (coupé), the Subaru Vortex, the Subaru RX, and the Subaru XT (Alcyone).

Summary of specifications
Model Years Size Compression ratio Valvetrain Output
Displacement Bore Stroke Power Torque
EA-52 1966–1970 977.2 cc
60 in3
72 mm
2.8 in
60 mm
2.4 in
9.0:1 OHV Pushrod 55 hp
41 kW; 56 PS @ 6000
57 lb⋅ft
77 N⋅m @ 3200
EA-53 1967–1968 10.0:1 OHV Pushrod, twin carburetor 67 hp
50 kW; 68 PS @ 6600
59 lb⋅ft; 80 N⋅m
8.2 kg⋅m @ 4600
EA-61 1969–1972 1,088 cc
66 in3
76 mm
3.0 in
8.5:1 OHV Pushrod 61 hp
45 kW; 62 PS @ 5600
65 lb⋅ft
88 N⋅m @ 4000
EA-62 (regular) 1971–1972 1,267.5 cc
77 in3
82 mm
3.2 in
9.0:1 OHV Pushrod 80 hp
60 kW; 81 PS @ 6400
73 lb⋅ft
99 N⋅m @ 4000
EA-62S 1969–1972 10.0:1 OHV Pushrod, twin carburetor 92 hp
69 kW; 93 PS @ 7000
76 lb⋅ft
103 N⋅m @ 5000
EA-63 (JDM)[2] 1973–1979 1,361 cc
83 in3
85 mm
3.3 in
8.5:1 OHV Pushrod 71–77 hp
53–57 kW; 72–78 PS @ 6000
74–76 lb⋅ft
100–103 N⋅m @ 3600–4000
(US) 1973–1976 58 hp
43 kW; 59 PS @ 5600
68 lb⋅ft
92 N⋅m @ 2400
EA-64 1973–1979 1,176 cc
72 in3
79 mm
3.1 in
9.0:1 OHV Pushrod 68 hp
51 kW; 69 PS @ 6000
69 lb⋅ft
94 N⋅m @ 3600
EA-65 1979–1994 1,298 cc
79 in3
83 mm
3.3 in
65 hp
48 kW; 66 PS @ 5600
85 lb⋅ft
115 N⋅m @ 3200
EA-71 (JDM) 1976–1994 1,595 cc
97 in3
92 mm
3.6 in
9.0:1 OHV Pushrod chain drive 81–86 hp
60–64 kW; 82–87 PS @ 5600
87–89 lb⋅ft
118–121 N⋅m @ 3600
EA-71S (JDM) 1976–1994 OHV Pushrod chain drive, twin carb 94 hp
70 kW; 95 PS @ 6400
89 lb⋅ft
121 N⋅m @ 4000
(US) 1976–1979 OHV Pushrod chain drive 67 hp
50 kW; 68 PS @ 5200
81 lb⋅ft
110 N⋅m @ 2400
(US) 1980–1987 OHV Pushrod 68 hp
51 kW; 69 PS @ 4800
84 lb⋅ft
114 N⋅m @ 2800
EA-72 never released 8.7:1 SOHC not published
EA-81 (US) 1980–1994 1,781 cc
109 in3
67 mm
2.6 in
8.7:1 OHV Pushrod 73 hp
54 kW; 74 PS @ 4800
94 lb⋅ft
127 N⋅m @ 2400
(EU) 79–81 hp
59–60 kW; 80–82 PS @ 6000
97 lb⋅ft
132 N⋅m @ 2400
EA-81T (turbo) 1983–1984 7.7:1 OHV Pushrod 95 hp
71 kW; 96 PS @ 4200
123 lb⋅ft
167 N⋅m @ 2800
EA-82 (carb) 1984–1994 8.7/9.0:1 SOHC, carburetor 84 hp
63 kW; 85 PS @ 5200
101 lb⋅ft
137 N⋅m @ 3200
(SPFI) 9.0:1 SOHC, SPFI 90 hp
67 kW; 91 PS @ 5600
101 lb⋅ft
137 N⋅m @ 3200
(MPFI) 9.5:1 SOHC, MPFI 97 hp
72 kW; 98 PS @ 5200
103 lb⋅ft
140 N⋅m @ 3200
EA-82T (turbo) USA 1984–1990 7.7:1 SOHC, MPFI 111–115 hp
83–86 kW; 113–117 PS @ 5200
134 lb⋅ft
182 N⋅m @ 2800
EA-82T (turbo) Europe/Japan 1984–1990 7.7:1 SOHC, MPFI 134–136 hp
100–101 kW; 136–138 PS @ 5200
145 lb⋅ft
197 N⋅m @ 2800
EA82T (turbo)

Works Group A/B

1984-1988 7.5:1 SOHC, MPFI 180–190 hp
134–142 kW; 182–193 PS @ 6450
170 lb⋅ft
230 N⋅m @ 5200

Models edit

EA-52 edit

The Subaru EA-52 engine was produced from 1966 until 1970.

Found on edit

EA-53 edit

The Subaru EA-53 was used in the 1967 Subaru 1000 Sports Sedan, sold in Japan. It used twin carburetors. This engine was used in the September 1968 Japan Alpine Rally which the car won in the 1000cc engine class.

EA-61 edit

 
Subaru EA61 1.1L

The Subaru EA-61 engine was produced from 1969 to 1972. The Japanese-spec Subaru FF-1 Sport Sedan and the FF-1 Super Touring sedan used twin carburetors, with the engine designation EA-61S. It was sold in the United States only for the 1971 model year.[3] It was also briefly available in the first Leone, only in 1100 Van specification.

Found on edit

EA-62 edit

The Subaru EA-62 engine was produced from 1971 to 1972. It is the only EA- engine with rear-facing exhaust ports.

Found on edit

EA-62S edit

This engine used twin carburetors from Zenith-Stromberg.

Found on edit

EA-63 edit

The Subaru EA-63 engine was produced from 1973 to 1979, although it stopped being used in US-market cars in 1976.

Found on edit

EA-64 edit

The Subaru EA-64 engine was produced from 1973 to 1979. The engine disappeared from the sedan catalogs in September 1975, as the new emissions regulations would simply make the car too slow. As commercial vehicles didn't have to meet the new stricter regulations, it continued to be available in the Van 1200 Standard until the end of production of the first generation Leone in 1979.

Found on edit

EA-65 edit

The Subaru EA-65 engine was produced from 1979 to 1994.

Found on edit

  • 1979-1994 Subaru Leone for Japanese domestic market, Europe, Asia and Latin America.

EA-71 edit

The Subaru EA-71 engine was produced in two different designs; from 1976 to 1994, originally the first design was a redesign of the EA-63 block, known as the "Narrow Case EA71" then Subaru completely redesigned it to make the newer version known as "Fat Case EA71" which also led to a stroked version known as the EA81. The availability in USA for the EA71 ended in 1990 on the hatchback models. It came with a carburetor and the last editions for JDM featured throttle-body injection, found on the "Maia" editions of the third generation Subaru Leone. The engine came either with solid lifters or hydraulic lifters.

 
Subaru EA-71 Engine

Found on edit

EA-71S edit

This engine used twin Hitachi carburetors.

Found on edit
  • 1979-1981 Subaru Hatchback
  • 1979-1980 Subaru Brat
  • 1979-1983 Subaru Manatee (Race car, JDM)

EA-72 Concept Engine edit

There was an unreleased EA-72 concept engine Subaru developed for use in the Japanese Market in 1989. It was essentially an EA-82 with an EA-71 crankshaft. This engine never came about as the Subaru EJ15 and EJ16 were already in development for this purpose.

Specifications edit

  • Displacement: 1,595 cc
  • Bore: 92 mm
  • Stroke: 60 mm
  • Compression Ratio: 8.7:1
  • Valvetrain: SOHC
  • Horsepower: unreleased
  • Torque: unreleased

EA-81 edit

The Subaru EA-81 engine was produced from 1980 to 1994 and is a stroked version of the "Fat Case" EA-71 it came either with Solid Lifters or Hydraulic Lifters.

Found on edit

EA-81S edit

This engine used twin Hitachi carburetors on a single intake manifold, and the late version for the 1983 Safari Rally, featured two downdraft Weber Carburetors, each one mounted directly over each head. The Heads and Valvetrain on the EA81S engines are different from the regular counterparts, featuring different positions for the intake and exhaust valves on the Heads, feature known usually as Reverse Valves.

Found on edit

EA-81T edit

The EA-81T is not an official engine designation from Subaru. The "T" is used informally to refer to the factory turbocharged version of EA-81 engines that are equipped with a turbocharger and multi port fuel injection. Boost pressure was 7 psi.

Found on edit

EA-82 edit

 
Subaru EA-82 Engine (displayed upside-down)

The Subaru EA-82 engine was originally intended to be a 2.0L engine as its prototypes were, but Subaru destroked it to 1.8L for production. The EA82 was produced from 1984 to 1994. It came either with carburetor, single point fuel injection, or multi port fuel injection and hydraulic lifters. Most of the technical advancements introduced to the EA82 were utilized in the next generation Subaru EJ engine, specifically, the SOHC valvetrain, and multi-point fuel injection.

Found on edit

EA-82T edit

The EA-82T engine was introduced in 1984 for the Third generation of Subaru Leone in the GL-10 and RX Turbo trim models plus the XT (Vortex), and later on the Subaru Leone RX Coupe models. It is a turbocharged version of the MPFI EA-82 with modified cylinder heads, lower compression pistons, and boost pressure of 7 psi

A revised intake known as the "Spider" manifold was available and is seen as an early version of the EJ style intake manifold.

ER27 edit

Subaru ER engine
Overview
ManufacturerSubaru
Production1988–1991
Layout
Configurationflat-6 petrol engine
Displacement2.7 L (2672 cc)
Cylinder bore92 mm
Piston stroke67 mm
Cylinder block materialaluminium
Cylinder head materialaluminium
ValvetrainSOHC
Combustion
Fuel typePetrol/gasoline
Output
Power output112 kW (150 hp)
Chronology
SuccessorSubaru EG engine

The ER series is a flat-6 engine with a displacement of 2.7L manufactured by Subaru, a division of Fuji Heavy Industries. The ER series has aluminium engine blocks and aluminium cylinder heads. It is found on the 1988-1991 Subaru Alcyone VX (XT-6 in the United States).

Created as a refined luxury engine with improved power over the EA82T, Subaru introduced the ER series engine in 1988 exclusively to be featured in the Subaru Alcyone VX. Like the EA series engines, the ER series engine featured 2-valve cylinder heads with hydraulic lash adjusters and the block shared the same bore and stroke. While recognised as bearing many similarities to the Subaru EA82 engine, there are numerous differences in design between the two engines and a large portion of parts are unique to the ER27. The oil and water pumps are unique to the ER27, sharing similar bolt patterns and design to the EA82, but being of a higher flow in both cases.[4] The intake manifold uses a two piece design with a lower section bolting to the heads containing the coolant bridge, injectors and various vacuum lines. The upper intake manifold then bolts to the lower section and is unlike the EA82 or EJ22 "spider" manifold designs in that there is no central plenum chamber. The valve timing system is belt-drive using two individual timing belts, curiously one belt uses a spring tensioner (like the EA82) whilst the other uses a hydraulic tensioner (like the EJ22). Both JDM and USDM versions of the ER27 used multi-point electronic fuel injection. The ER27 designation was the first time Subaru incorporated the engine's displacement into the series name and all future engines have retained this nomenclature.

References edit

  1. ^ Ernst, Kurt (May 12, 2016). "Subaru's boxer engine celebrates its golden anniversary". Hemmings. Retrieved 17 March 2022.
  2. ^ a b 新型Subaru Leone (catalog) [New Subaru Leone] (in Japanese), Fuji Heavy Industries, June 1978
  3. ^ Flammang, James M. (1994). Standard Catalog of Imported Cars, 1946-1990. Iola, WI: Krause Publications, Inc. p. 588. ISBN 0-87341-158-7.
  4. ^ "Oil Pump & Water Pump differences EA82->ER27". March 16, 2010. Retrieved 2011-05-06.
  • 1977 Subaru Factory Service Manual
  • 1983 Subaru Factory Service Manual
  • 1984 Subaru Factory Service Manual
  • 1987/1988 Subaru Factory Service Manual
  • Subaru Drive Magazine