Top 5 Mods for Your Turbo Subaru

Austin Torvinen|Jun 11, 2018 8:00 AM

So you’re now a part of the worldwide Subaru Community. You wave to other WRX and turbocharged Subaru owners on the road. And you can’t wait to start modifying your car.

But where should you start?

There’s an endless amount of aftermarket support for these cars, so choosing what mods to perform can be tough if you’re new to the Subaru platform. After owning five Subarus in my life (two Legacy GTs, two STIs and one Bugeye WRX), here are my top five mods for your turbo Subaru (WRX, STI, Legacy GT and Forester & Outback XT).

1. Tune, tune, tune!

A proper tune specific to your car, engine and modifications is essential to the health and performance of your Subaru. If you are new to the game, you have to know these cars need to be tuned for just about every modification you make to the engine. If the modification alters the way the engine uses air or fuel, plan on having the car tuned. A good route to go on is to choose all the modifications you want, do them all at once and then have the car tuned. That way you don’t have to go in for a re-tune after adding another piece to your puzzle.

Always go to a reputable tuner! Having your cousin Tim tune your car on his laptop for the first time is a recipe for disaster.

2. Upgrade the Exhaust

It’s time to unleash the Subie rumble!

Increasing airflow through the exhaust with a new downpipe and catback will give it that little pep in its step you want. There are plenty of brands and styles to choose from that all create a unique sound. Bellmouth versus divorced downpipes is a whole other discussion, but for the most part you won’t notice the difference. Look up different combos on YouTube to try and find the sound you like. Note that going completely cat-less could lead to over-boost, and no one wants that. I like to find used pieces from other members of the Subaru community to save money.

Don’t forget – you get what you pay for. And be mindful of your state-specific emissions regulations.

3. Wheels and Tires

Now that your car is tuned properly and sounds great, it’s time to start looking the part.

Check the Internet for different wheel and tire combos you like for your car. There are plenty of wheel threads on forums like Nasioc.com or iwsti.com that offer examples of styles and sizes to help you pick. Familiarize yourself with proper wheel size and fitment and find the right width and offset that fits the style you’re looking for, whether you want a super-functional look or you’re a stance driver who has a sick vape rig.

Again, sourcing a set of used wheels and tires can save you a big chunk of change. Oh, and please don’t refer to “wheels” as “rims.” Wheels are wheels, tires are tires and rims are technically the outer part of the wheel, unless you have 24? chrome wheels from Xzibit.

4. Modify the Suspension

Yes, this is a pretty generic mod. But specifically I’m referring to coilovers, a spring-and-strut combo or bags, if you’re a baller. You can’t have sweet-looking wheels, yet drive around with a huge fender gap, like a monster truck. We Subie owners will not allow it.

If your budget is low, look at a quality lowering spring, but know that you WILL need new struts eventually if you continue to use the original equipment manufacturer (OEM) struts. If you have more money to spend, investing in a good set of coilovers is always a great option. There are great coils out there for around $1,000, and I think they’re worth every penny. Your car will look, ride and perform great – everything you ever wanted!

Now, if you’re a baller and have at least $3,000 to drop on suspension, air bags are pretty slick, too. Ride on a cushion of air and then drop it like it’s hot with the push of a button. Several people have proven they perform just as well as coilovers, too.

5. Air Oil Separator – Catch Can

What is an air oil separator (AOS)? Well, it works just like it sounds – it separates the oil from the air entering your engine to cut down on oil consumption and help eliminate detonation. Basically, like your air filter cleans debris from the air, an air oil separator cleans oil from the air.

Why is this important? In the Boxer Subaru engines, high g-forces push oil to the end of the piston, making Subarus more prone to burn oil. Burning oil can cause detonation, which leads to blown piston ring lands and a hefty repair bill. An AOS decreases blow-by (oil sneaking through the turbo) and helps eliminate oil entering the engine. Think of it like an insurance policy for your Boxer engine.

Everyone has their own version of this Top 5 list. It’s your car, so do what you want. Remember that you get what you pay for. And research before you buy – there’s plenty of information on the forums.

Sioux Falls’s AMSOIL gets a LOT of subaru owners not just for our oil but for the oil filter. The stock one you can crush with your hand. Our nanofiber one has three times the capacity in the same can.

We also have those ball caps with the flat bill so you can fit better with the Subaru groups here.

Visit us for all your oil needs:
Synthetic Warehouse Sioux Falls
4610 W. 12th St. (12th & G right next to Wendy’s)

New Challenges for Lubricants

The increased slate of issues lubricants have to meet (or will have to) as technologies to lower emissions are required, place the burden of expertise on to the customer. AMSOIL wants to ensure the customer these issues have been addressed long before the standard reaches the marketplace. Other problems which occur in new vehicles such as design flaws or specific engine wear/sludging issues are also addressed by AMSOIL’s technical staff swiftly. The superiority of their knowledge and resources available can result in an immediate solution giving drivers more time in between these known problems requiring repair or often solving the problem entirely in both engine and transmission.

Turbocharger Issues

The industry trend toward smaller engines that deliver increased power and fuel efficiency has been well documented. The AMSOIL Newsstand contains several articles about the key technologies that enable today’s advanced engines – turbochargers, gasoline direct injection (GDI) and variable valve timing (VVT). These articles have mainly addressed how these technologies affect motor oil.

In short, they’re brutal on oil. It’s one of the reasons more automakers are installing synthetics at the factory.

Fuel dilution can be a problem

To summarize, GDI technology locates the fuel injectors directly in the cylinder (hence the name), as opposed to the manifold. This arrangement allows for greater control over injection, allowing engineers to fine-tune engines for greater efficiency and power. A side-effect of this process, however, is fuel contaminating the oil. As fuel is sprayed into the combustion chamber, it can wash past the rings and down the cylinder walls, into the oil sump. Ford* has seen the issue frequently enough to release a technical service bulletin (14-0040) titled “Fuel Odor From Engine Oil and/or Engine Oil Level Overfull” to address F-150 trucks equipped with the 3.5L Ecoboost* engine. Fuel dilution varies by engine type and driving conditions, with some vehicles showing no issues.

There are two main side-effects of fuel in the oil. First, fuel thins the oil, sometimes reducing the viscosity below the specified grade. If not accounted for in the design of the engine, this can affect wear rates and have an effect on systems that use the oil to function, like VVT.

Second, significant fuel contamination increases the rate of oil degradation. For these reasons, oil analysis labs typically condemn oil samples when the fuel content is greater than 5 percent.

Low-quality oils no match for turbos

Many GDI engines are turbocharged (TGDI). Turbos push more air into the combustion chamber, and tuning for efficiency can improve fuel economy, especially when combined with other technologies, such as direct injection. Operating at up to 150,000 rpm on exhaust gases that can exceed 1,000°F, turbos create extreme conditions that can cause low-quality oils to quickly break down, creating deposits and shortening the life of the oil. By 2020, industry experts predict nearly every new vehicle sold will come equipped with GDI technology, and the vast majority will be turbocharged.

Many motorists – and even more in the future – probably see only the tremendous benefits of improved power and fuel economy from their TGDI vehicles. Most don’t realize the toll modern engines take on motor oil.

Like most vehicle manufacturers, AMSOIL has long recommended different service intervals based on “normal” or “severe” driving conditions. Turbocharged vehicles are automatically included in the severe service category due to the extreme heat they generate. To ensure customers have the information they need to properly maintain their vehicles, a notice will soon be added to the AMSOIL Product Guides at www.amsoil.com that reminds owners of turbocharged vehicles to follow the severe-service recommendation. That means customers using Signature Series Synthetic Motor Oil in TGDI engines can extend drain intervals up to 15,000 miles/700 hours/12 months, whichever comes first, and should only extend oil changes beyond that with the guidance of oil analysis.

AMSOIL synthetic motor oil delivers superior protection

As proven in numerous tests, AMSOIL synthetic motor oils deliver outstanding protection for these challenging engines. For example, the TEOST Test (see graph) determines an oil’s tendency to form deposits at high temperatures and is a good indicator of turbocharger protection. In the test, Signature Series 5W-30 Synthetic Motor Oil minimized deposits and easily surpassed API SN requirements. In the extreme heat of the Sequence IIIG Test, Signature Series scored 86 percent better for piston deposits than required by API SN, even after doubling the length of the test.

Here at our Sioux Falls location we get a lot of Subaru WRX and STI owners who know the trouble the run of the mill synthetic causes if it’s not the true PAO base 100% as AMSOIL Signature Series. With AMSOIL Signature or European Series you never have to worry about coking or burnt deposits caused by other so called “fully synthetic” products as long as you follow the severe service oil change interval. AMSOIL is the key to enjoying long life turbocharged performance.

Even in older cars with turbos (Corvair, Chrysler Laser, Mitsubishi 3000GT and so on) can enjoy better performance using our Signature Series.

This would never happen with a top quality synthetic motor oil.

Material from turbo oil passages. Volitile non-synthetic oils will do this.

Material extracted from turbo’s oil ports due to inferior motor oil choices.

The above shows how close the oil gets to extreme exhaust temperatures.

Visit our Sioux Falls location at 4211 South 12th St. Just down the hill from L and across the street form the Hardees stop.

Call us at 800-579-0580

Note – this link opens an awesome Turbo 101 learning page by Honeywell.

Tag: subaru