What makes a great Subaru engine? A great Subaru engine combines power, performance, and reliability in a way that allows the vehicle to reach its full potential.
Figure 1: A Subaru FB20 engine. Fountain:Autoblog.
Motors SubaruThey are known for the superior quality of their OEM parts.Years of research and experimentation have gone into Subaru engines.That's why many drivers choose to leave their engines in perfect OEM condition. But for those who want to do some customization, SubaruThe engines are also great aftermarket engines, thanksdue to its high reliability and durable parts and performance.
In this post, we will look at some of the best and most important ones.Engines in Subaru history.. From the original E-series, when it was first introduced in the US, to the completely redesigned modern F-series, there have been many great Subaru engines.
We'll look at engines from an OEM and aftermarket standpoint.
Fuentes:How is Crawford doing?.
Figure 2: This Subaru FB20D 2.0L is the heart of the modern Impreza. Fountain:J-Spec Auto.
The FB series was initiallyAvailable as naturally aspirated engines.with a displacement of 2.5 liters and 2.0 liters. like the first newengine generationFrom Subaru since the EJ series and the manufacturer's third-generation flat-four engine, expectations were high when the FB was first announced in 2010.
DieThe engines had a sharp increase in piston stroke.and diameter reduction, which was primarily aimed at reducing emissions and increasing fuel economy without compromising engine performance. That's rightfuel economyIt hadn't been one of Subaru's strong points until now, so these improvements were a very welcome addition to the FB range.
Also the new FB engines.allowed a reduction of 28%in friction losses compared to previous models, mainly due to lighter pistons and connecting rods. This had another, perhaps unintended effect: an increase in torque compared to previous generations of Subaru engines. Whether that was your primary goal or just a happy accident, we think the extra torque made a world of difference.
Figure 3: This 2017 Impreza GK is equipped with an FB20D engine. Fountain:NRMA.
We picked the FB20D as the best of the bunch. Because? Because unlike the FB20B that came before it, the FB20D is includeddirect injectionwhich provides a noticeable increase in power and efficiency. This engine is used in the fifth-generation Impreza hatchback and saloon, and that extra power makes a world of difference. Thatengine characteristicsa compression ratio of 12.5:1 when used in the Subaru Impreza. This will give your vehicle 152 horsepower at 6000 rpm and 145 lb-ft of torque.
This engine is used in the 1995cc DOHC, 2017+ Subaru Impreza and 2018+ Subaru XV.
Figure 4: The EZ36D engine. Fountain:Subarucar.net.
The EZ36 engine is the king of Subaru six-cylinder engines. Compared to previous EZ30 six-cylinder engines, the EZ36 has a larger bore and stroke, while incorporating thinner iron cylinder liners to accommodate the larger bore. With asymmetrical cranks, the stroke increases proportionally. Interestingly, the body of the engine itself is slightly longer than other Subaru engines, largely due to modifications to the drive cam.
Figure 5: This 2019 Outback might as well handle thisall the benefits of the EZ36D six-cylinder engine. Bron:chasing cars.
The EZ36D was used in theinterior de subaru(particularly the 3.6R) from 2010 to 2019. It made 256 horsepower at 6000 rpm, an impressive number to be sure, while managing 247 lb-ft of torque at 4400 rpm. It is known to be a bit more reliable than its EZ30 siblings. It's also a great candidate for a supercharger kit.
The EZ36D, to the extent that it has engine issues, generally has the same issues and easy fixes as the EZ30. Clickherefor more information on common problems.
This cute little engine is the Subaru EJ257. It's a 2.5-liter engine that has its roots in rally racing, but it's a great all-purpose Subaru engine. Originally designed for the 2004 USDM Impreza WRX STI.The engine comes complete with a horizontally opposed 4 cylinder engine.institutions. This allows the center of gravity to be lowered.
This engine has a bore and stroke of 3.92" by 3.11", peak power of 300 hp at 6,000 rpm and peak torque of 290 lb-ft at 4,000 rpm.
Figure 6: The 2004-2007 Impreza WRX STI proudly received the EJ257 engine. Fountain:hagerty.
The onlycar in the US using the EJ257 engineis the STI. OtherCars with 2.5 liter EJ series engine.Use the EJ255. Interestingly, several cars were produced between 2004 and 2006.technicallyhad EJ257engines, even if their engines were officially designatedlike EJ255. These were:
- Forestal XT 2004-2005
- Legacy GT 2005-2006
- InteriorXT 2005-2006
This engine has relatively large bores and relatively short strokes. This is important because it allows the engine to produce enormous torque even in stock. If that wasn't enough, Subaru's special AVCS (which Activevalve control systemfor you) allows variable valve timing with the intake valves.
The engine also comes with an intake camshaft controlled by the car's ECU. It can be adjusted up to 35 degrees, allowing cam timing to be optimized throughout the entire RPM range. In addition to all these features, the EJ257 is known as onegreat aftermarket engine.
Note that the EJ257 occasionally has piston related issues. The remains of broken rings sometimes caused the engines to explode. Interestingly, it also makes a strange and peculiar exhaust sound that some drivers find irritating. But hey, if you prefer that melodic note of the boxer engine, then you have more power!
4. Subaru EJ20T WRX STI
Figure 7: An EJ20T engine safely housed in an Impreza STI. Fountain:car speed.
These flat-four boxer engines are found primarily in the performance-oriented STI and WRX versions of the Impreza. This engine is another great aftermarket option because it is affordable, available, and can provide a good amount of power and torque. Interestingly, while the conventional Impreza and other members of the Subaru family switched to the 'Subaru Global Platform' several years ago, the high-performance WRX and WRX STI models of the Impreza have yet to do so. They are still based on the previous generation Impreza.engine models. However, this does not mean that the classic engines are less impressive.
Note that EJ20T is not actually a Subaru code. Instead, this term is used by enthusiasts and experts.denotes the entire line of turbochargersEngines available for STI or WRX. This practice began with the designation of the US-spec turbo, often referred to as the "EJ22T". From then on the custom is to refer to allturbo engineshow a "T" started.
a typicalthe engine gets a powerband197 hp at 6,000 rpm. The power of the GT is around 217 hp at 6,400 rpm. These engines are easy to identify bycoil in plug, with 2 M6 screws per coil and valve covers labeled 4CAM 16VALVE. In addition, the horizontal lines above and below the plug holes are also clearly visible. All of these engines have an air-to-water intercooler configuration and closed deck blocks fitted with piston oil ejectors.
We spoke to the experts at CrawfordPerformance vs. your Subaru engineoptions for WRX and STI owners. They explained that they offer engines in 4 tiers, from "OEM short blocks for people who just want to replace the stock blocks, to Tier 4, which is a crazy racing level that will make 600-700 horsepower."
Figure 8: A 2017 Subaru WRX STI. Source:automatic guidance.
Tier 3 includes Subaru S3 engines. Crawford's S3 "basically has Crawford designed JE pistons and connecting rods, along with a brand new stock block. This is about $3,500." However, they added that "you also need a shortblock installation kit because you have to change the oil and stuff. That will cost another $800."
As they explained, “It all comes down to whether or not you have a good tuner. If you go beyond the original OEM power range, make sure you have a good tuner. Otherwise, the motor will suffer serious problems and have a shorter life.
“Besides buying the block and installing it, the most important factor is the tune,” the experts and Crawford emphasized. Finally: “Make sure you have an air-oil separatorExtends the life of any engine.have."