Subaru launched the production of EJ engines in 1989 and 2.0L EJ20 was the debut one of the series. It was created as an alternative to EA82 1.8L motor and soon, it turned into the main engine for all Subaru vehicles.
Like its predecessor, EJ20 is a 4-cylinder opposed to gasoline motor. It features an aluminum cylinder block with dry cast iron sleeves. EJ20E is the most famous engine of the range. It’s naturally aspirated and features two SOHC cylinder heads with 4 valves per cylinder. The size of the intake valve is 36 mm while the exhaust valve is 32 mm. Camshafts are controlled by a timing belt from crankshaft, which needs to be replaced after every 60,000 miles run.
EJ20E has got 4 modifications, which vary in capacity: 125, 135, 155 and 140 HP at 5,600 rpm, employed for Subaru Legacy BL automobiles. Simultaneously, EJ20D, a naturally aspirated DOHC engine with an output of 150 HP at 6,800 rpm, was produced.
Subaru launched the manufacture of SOHC motors with open block. Among them are EJ201 and EJ202. These motors feature other SOHC cylinder heads, light pistons and low revs adjusted intake manifold. EJ201 produces 125 HP at 5,600 rpm. EJ202 has output of 138 HP at 5,600 rpm and a torque of 187 Nm (138 ft-lb) at 4,400 rpm. Its better performance is explained by using light cylinder block, 4-2-1 exhaust manifolds and another intake manifold.
Moreover, there are also EJ203 and EJ204 engines. The first one features a mass air flow sensor and an electric throttle. EJ204 features double overhead camshaft cylinder heads and variable valve timing on intake camshafts, known as AVCS. Its capacity is 155 HP. Its later variation reaches output of 190 HP.
In 2019 Subaru has ended the production of the EJ20 series.
EJ20 Engine Specs
|Manufacturer||Gunma Oizumi Plant|
|Also called||Subaru EJ20|
|Cylinder block alloy||Aluminum|
2 valves per cylinder
4 valves per cylinder
|Piston stroke, mm (inch)||75 (3.62)|
|Cylinder bore, mm (inch)||92 (3.86)|
|Compression ratio||8.0 (EJ205 WRX/EJ207/EJ20G/EJ20K)
8.5 (EJ205 Forester/EJ208)
9.0 (EJ205 WRX 2002+/EJ206/EJ208)
10.0 (EJ204 Impreza II)
10.2 (EJ204 Impreza III)
|Displacement||1994 cc (338.8 cu in)|
|Power output||224 kW (125 HP) at 5,500 rpm
239 kW (135 HP) at 5,600 rpm
298 kW (137 HP) at 5,600 rpm
300 kW (140 HP) at 5,600 rpm
224 kW (155 HP) at 6,400 rpm
239 kW (160 HP) at 6,400 rpm
298 kW (180 HP) at 6,800 rpm
300 kW (190 HP) at 7,100 rpm
224 kW (200 HP) at 6,000 rpm
239 kW (220 HP) at 6,400 rpm
298 kW (230 HP) at 5,600 rpm
300 kW (240 HP) at 6,000 rpm
224 kW (250 HP) at 6,000 rpm
239 kW (260 HP) at 6,000 rpm
298 kW (260 HP) at 6,500 rpm
300 kW (275 HP) at 6,500 rpm
224 kW (280 HP) at 6,500 rpm
239 kW (308 HP) at 6,400 rpm
298 kW (320 HP) at 6,400 rpm
300 kW (328 HP) at 7,200 rpm
|Torque output||172 Nm (385 lb·ft) at 4,500 rpm
181 Nm (393 lb·ft) at 4,000 rpm
186 Nm (413 lb·ft) at 3,600 rpm
186 Nm (406 lb·ft) at 4,400 rpm
196 Nm (385 lb·ft) at 3,200 rpm
186 Nm (393 lb·ft) at 3,200 rpm
196 Nm (413 lb·ft) at 4,400 rpm
196 Nm (406 lb·ft) at 4,400 rpm
260 Nm (385 lb·ft) at 3,600 rpm
270 Nm (393 lb·ft) at 4,000 rpm
319 Nm (413 lb·ft) at 2,800 rpm
309 Nm (406 lb·ft) at 4,000 rpm
334 Nm (385 lb·ft) at 3,600 rpm
319 Nm (393 lb·ft) at 5,000 rpm
309 Nm (413 lb·ft) at 5,000 rpm
319 Nm (406 lb·ft) at 4,000 rpm
343 Nm (385 lb·ft) at 5,000 rpm
430 Nm (393 lb·ft) at 4,400 rpm
384 Nm (413 lb·ft) at 4,400 rpm
431 Nm (406 lb·ft) at 4,800 rpm
|HP per liter||62.7
|Weight, kg (lbs)||147 (500) – EJ20G|
|Fuel consumption, L/100 km (mpg)
|for Impreza WRX STI GD
Mitsubishi TD04 (WRX)
Mitsubishi TD05H (WRX/STI)
Mitsubishi TF035 (WRX)
IHI RHF5HB (STI)
IHI VF28 (STI)
IHI VF30 (STI)
IHI VF34 (STi Spec C Type RA)
IHI VF35 (WRX Type RA)
IHI VF36 (STI Spec-C)
IHI VF37 (STI)
IHI VF42 (STI S203/S204)
|Oil consumption, L/1000 km
(qt. per miles)
|up to 1.0
(1 qt. per 600 miles)
Recommended engine oil
|Engine oil capacity, L (qt.)||4.0 1993-2007
4.5 WRX/STI 1993-2000
5.0 WRX/STI 2000-2007
|Oil change interval, km (miles)||5,000-10,000
|Normal engine operating temperature, °C (F)||–|
|Engine lifespan, km (miles)
- Subaru Forester
- Subaru Legacy
- Subaru Impreza
- Isuzu Aska
- SAAB 9-2X
EJ20 Engine Problems and Reliability
Though EJ engines are rather reliable, they may have some disadvantages. Here are the most widespread ones:
- Engine tapping. If you notice motor tapping in the fourth cylinder, it means that the cylinder has some troubles with cooling. As this cylinder is cooled worse than other ones, piston starts to tap. Initially, the motor taps at cold start and later permanently. Big repair is the sole solution of the problem.
- Oil leak. It’s recommended to examine camshaft seals and valve cover glands. As a rule, their malfunction causes leakage.
- High oil consumption. This trouble is common for turbo motors and means that piston rings don’t function. It’s necessary to replace engine oil after every 7500 kilometers run. Try to buy only high-quality oil.
Uncontinuous oil leaking?! That is a huge problem! Fortunately we know how to help. Read this top 10 radiator stop leak products.
In order to avoid a great number of troubles, it’s recommended to purchase only good quality engine oil for both naturally aspirated and turbocharged motors. The other piece of advice is to drive the car gently and don’t accelerate too fast.
If you plan to acquire Subaru Impreza STI with a turbocharged motor, take into account that the motor isn’t very durable and needs big repair after every 50,000-60,000 miles (100,000 kilometers) run.
In their turn, naturally aspirated EJ20 motors are more durable and trustworthy. They can run 150,000 miles (250,000 kilometers) and even more.
Cylinder Head Installation Torque Specs
- Install the cylinder head and gaskets on the cylinder block.
CAUTION: Use new cylinder head gaskets. Be careful not to scratch the mating surface of the cylinder head and cylinder block.
- Tighten the cylinder head bolts. Apply a coat of engine oil to washers and bolt threads. Tighten all bolts to 29 N.m (3.0 kgf-m, 22 ft-lb) in alphabetical sequence. Then tighten all bolts to 69 N-m (7.0 kgf-m, 51 ftIb) in alphabetical sequence. Back off all bolts by 180″ first; back them off by 180″ again. Tighten the bolts (A) and (B) to 34 N-m (3.5 kgf-m, 25 ft-lb). Tighten the bolts (C), (D), (E) and (F) to 15 N-m (1.5 kgf-m, 11 ft-lb). Tighten all bolts by 80 to 90″ in alphabetical sequence.
Do not tighten the bolts more than 90″. Further, tighten all bolts by 80 to 90″ in alphabetical sequence.
- Ensure the total “re-tightening angle” [in the two previous steps] do not exceed 180″. Install the camshaft.
- Install the A/C compressor bracket on the cylinder head.
- Install the intake manifold.
- Install the camshaft sprocket.
- Install the timing belt assembly.
- Install the belt cover.
- Install the crankshaft pulley.
- Install the V-belt.
Subaru EJ20 tuning
The tuning of an atmospheric EJ20 engine makes no sense. It is better to buy EJ205 and EJ207 and make the swap.
For tuning turbo EJ205 you need to buy an aluminum 2-row radiator (like Mishimoto), front-mount intercooler, intake from the STI, turbine VF30, blow-off, the oil pump from the WRX STI, the candles, the nozzle the STI, pump Walbro 255, the ACL inserts boost Controller, a complete exhaust system with 76 mm pipe. After setting up the control unit, you get about 300 hp
You can also slightly increase the working volume of up to 2.12 liters by setting the crankshaft with 79 mm piston stroke, H-shaped rods, Mahle pistons, ARP studs.
EJ207 Engine tuning starts with the purchase of a front intercooler, TD05-18G turbine blow-off the HKS, the injectors 800 cc, also need a reinforced timing belt, the cold inlet oil pump 12 mm oil cooler, exhaust manifold, 76mm exhaust and setting of the control unit. In this, you can get a 350+ hp. Also on the EJ207 you can make 2.2 liter working volume (2.123), as it’s described above.
Last update on 2022-01-15 / Affiliate links / Images from Amazon Product Advertising API