Subaru is best known for being one of a handful of manufacturers that produce a lineup of commercial vehicles with boxer engines. The difference here is that Subaru couples it with an AWD system. The only model from Subaru that doesn't come with an AWD drivetrain is the BRZ.

Another reason why Subaru is a well-known brand for reliability is thanks to its tried and true safety technologies as well as its overall ownership cost over the decades. You just can't go wrong with a Subaru but what you can go wrong with is a performance upgrade. Therefore, it's important to know what to look for in the first place.

Must-Have Performance Parts

Injectors

Your Subaru may have nothing wrong with its stock components, but if you want it to reach its full potential then you should consider getting Subaru performance parts such as injectors. With new injectors, you'll not only improve fuel efficiency but you'll also make the engine perform at its best. This is because these performance Subaru parts help deliver more fuel more efficiently into the combustion chamber which increases engine power.

Conrods

Better known as connecting rods, these metal Subaru parts are the link between the piston and crankshaft. Conrods are made to transfer the movement from the piston to the crankshaft and they should be able to do so without fail every single time. This is why going for performance conrods can help improve the transfer of that movement so that it's done more efficiently. There are also different types of conrods that will perform well in different engines.

For example, if you want to make your Subaru's engine able to bear more torque, then you should go for H-beam connecting rods. These Subaru parts make this happen thanks to their bigger and flatter sides as well as their narrow centre part.

An I-beam connecting rod is made with a wider profile and it's used in stock engines since it's lighter and helps make for a more fuel-efficient engine. H-beam conrods are the better option here but keep in mind that their size needs to be compatible otherwise you'll make for an engine that acts a bit different than what you're used to.

Pistons

The pistons are what generate the needed compression in the chamber in order to start the combustion process and keep it going. But not just any type of pistons will make your Subaru perform better. In this case, you need the ultimate Subaru performance parts and those are forged pistons. What makes forged pistons great for high-performance applications is their durability and strength.

Unlike cast pistons, which are found in stock engines, forged ones have a lower silicone content that makes them less brittle. Also, these Subaru custom parts are heavier which can be seen as a negative, but keep in mind that this is counteracted by their ability to make a high compression ratio. A high compression ratio means more torque and thus your Subaru is going to maintain speeds a lot easier.

Turbo

Subaru vehicles may not be known for making turbocharged engines but you can add a turbo yourself if you wanted to. Although this is quite a meticulous task, it will pay off big time. With a turbo, your Subaru will literally get a boost in power whenever you go over a certain RPM.

Although this power is only available at certain speeds it's never a bad idea to have it available. Even if you add a small turbo that only spools at a certain RPM, you'll notice a big difference in how your Subaru pulls even when travelling at low speeds. This will be great for getting out of a junction or going up a slip road.

Air Filter

Air is as important for engine performance as fuel. Without air, the combustion process wouldn't take place which is why you should go for a high-flow air filter. Although air filters might not look or sound like a performance upgrade these Subaru custom parts are a big one at that. Stock air filters might have become better over the years but they're nothing like having a cold air intake.

With more air being available, you improve the performance of the engine since it can “breathe” better. Also, cold air will keep the combustion chamber cooler at a more efficient rate and thus your engine won't overreact when you keep the pedal down for too long. Also, with a performance air filter, you will have cleaner air fed to the engine which also aids in performance.

Spark Plugs

While a set of new spark plugs won't increase HP or torque, it will definitely bring back the old lively soul of your Subaru's engine. This will especially be the case with iridium spark plugs which will also last you a lot longer than regular ones. New spark plugs will also prevent the engine from a rough idle and they'll help make acceleration have no lag or at least very little of it. New spark plugs, iridium or not, will also improve fuel consumption.