Stock BRZ Torque Dip Dyno Chart
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The 5 Best Subaru BRZ, FRS, GT86 Performance Mods

Jake Mayock

Meet Jake

Jake is a founder of 8020 Media and TuningPro. He has over a decade of experience in the automotive industry including parts sales, writing, DIY modifications & repairs, and more. Jake is currently converting his N54 to a single turbo and building a Miata track car. He’s an experienced, hands-on automotive enthusiast who delivers in-depth, well-researched content.

The 2.0L BRZ produced 197-205hp and 151-156lb-ft. of torque. While these numbers might not seem very appealing, the approx. 2,700lb curb weight of these cars makes them a joy to drive.

However, if their 7.6 second 0-62mph time doesn’t excite you, there are a handful of simple BRZ performance mods that can be bolted-on to give these small engines a little more oomph. With a few upgrades including tuning, a cold air intake, headers, exhaust, and E85 fueling, we can add about 50whp. All-in this will cost you a few thousand bucks. We’re going to discuss each one of these upgrades including their performance benefits in-depth below.

Looking for suspension and handling mods? Check out our BRZ, FRS, GT86 Coilover Upgrade Guide.

The 4,000 RPM Power Drop

The natural power band for a stock FA20 has a dreadful torque drop from the 3,500 to 4,000 rpm range. This can make things feel really sluggish in the mid range as you accelerate.

The cause of the torque drop is predominantly caused by the design of the OEM exhaust manifold/headers. Therefore, we can fortunately smooth this dip out through the addition of some performance headers and a proper flash tune or custom tune.

BRZ, FRS, GT-86 Performance Mods - Best FA20 Upgrades

BRZ Performance Mods

  • Intake
  • Headers
  • Catback Exhaust
  • Tune
  • E85 Fuel

To produce serious power with your BRZ you will need to look into forced induction, but we’ll leave that for another guide. There are a lot of other considerations that go into FI such as fueling, tuning, and cooling which is a lot of detail to get into.

1) Cold Air Intake

The stock intake system on the FA20 engine isn’t necessarily optimized for airflow. It is instead rather restrictive and can therefore limit your performance potential. Upgraded intakes, also commonly called cold air intakes, will increase air flow by upwards of 50%. While an intake doesn’t need to be the first mod you add, we do recommend adding one at some point as more power requires more air.

Upgraded MAF Piping

The stock BRZ intake system technically has two different sections. First one is the intake box and associated piping which connects to the MAF sensor piping. The second piece is the MAF sensor piping which is between the first section and the intake manifold.

Replacing the MAF sensor piping with an upgraded piping can add an additional 5whp. While it does add about $150 to the total cost, it’s a good upgrade to get a bit more out of the intake system.

Intake Benefits

  • Approx. +10whp and +8wtq gains
  • Extra +5whp gains with upgraded MAF piping
  • Slightly colder intake air temps
  • 50%+ increase in airflow
  • Cool intake noise under acceleration

2) Headers

As we discussed above, the torque dip is caused in part by the design of the exhaust manifold. Therefore a great mod is upgrading the exhaust manifold with a set of performance headers. Exhaust manifolds create back pressure since air from the exhaust ports is funneled into one chamber. Headers remove that restriction by giving each exhaust port its own piping, which then meet together right before the catalytic converter.

On the BRZ’s the exhaust system goes in this order: headers, over-pipe, front-pipe which houses the catalytic convert, mid-pipe, and then muffler. The FA20 engines have unequal length headers from the factory, a common Subaru engine trait. This means that two of the exhaust ports have longer piping than the other two.

At the end of the day your two options are equal length or unequal length headers. Both make the same power levels so whichever you choose is up to you, here is a link if you want to check out the difference between UEL and EL headers.

Here is a picture of the OEM header compared to a set of performance headers, for reference:

BRZ OEM vs Performance Headers

Headers Benefits

  • ~10whp and ~8wtq gains
  • Slightly deeper exhaust note
  • Reduced backpressure
  • Improved throttle response
  • Partially fixes 4k rpm dip

3) Catback Exhaust System

Before we get into catbacks, there are two other components that can be upgraded before we get to the cat-back part of the exhaust. The over-pipe and the front-pipe are two components which can be upgraded for more power. While removing the cat in the front-pipe or opting for a high-flow option would usually add some solid power, it isn’t necessarily the case on the FA20.

Per dyno tuning a catless front-pipe only added 5whp over the stock pipe. That means a high-flow catted option would probably make like 2whp, and you can probably expect another 1-2whp from the overpipe. Overall, the power gains here just aren’t worth the cost in our opinion.

So onto cat-back systems. Dyno charts show power gains around 8whp for a cat-back exhaust on the BRZ. This is quite good for a naturally aspirated engine, plus you get the benefits of the better looking exhaust tips and louder exhaust notes.

Catback Exhaust Benefits

  • Approx. 8whp and 5wtq
  • Car looks a lot better from the rear with beefier exhaust tips
  • Louder and deeper exhaust tone, you can’t even hear the exhaust on a stock system
  • Improved exhaust flow

4) Flash Tuning

To be fair, the power numbers quoted for the mods above probably aren’t accurate until you’ve added a tune. Adding a tune in conjunction with these other modifications is where you really achieve the power gains out of the FA20 engine.

Additionally, a flash tune is the most important component of eliminating the torque dip so it’s a must have. We only have this at number 4 on our list because the power gains from a tune are amplified when you have the above 3 mods so it’s always great to combo them together.

Flash tunes connect into the ECU and essentially reprogram various components like ignition timing, air-to-fuel ratios, and other variables to increase power. Flash tuning devices can also run custom tunes that were compiled via dyno tuning or data logging.

For the FA20 there are really only two flash tuning options: Vishnu or EcuTek.

Benefits

  • +8-12whp and wtq gains on pump gas (up to 25whp and wtq with below E85 mod)
  • Plug-and-play
  • Ability to turn tunes on and off on the fly, change maps, etc.
  • Supports custom tuning
  • Removes torque dip (when paired with headers)
  • Smoother power band
  • Better throttle response

5) E85 Fueling Mod

A tune will add around 10whp on pump gas, in addition to the power gains from the other mods listed. However, when a tune is used in conjunction with BRZ E85 fueling mods it can add up to 25whp, meaning that E85 fueling alone can get you another 15whp.

The fortunate part of not having a turbo in these cars is that they received both port and direct fuel injection. Having both fueling capabilities means that these cars can easily run full E85 fuel relatively easily. The turbo version of this engine only uses direct injection which means it needs a lot more fueling upgrades to run 100% E85.

While it isn’t as simple as purely putting E85 in the tank, the only thing you need to run full E85 is a tune. No fueling upgrades are needed.

E85 Performance Benefits

  • +15whp and torque gains, about 25whp/wtq in total with the tune
  • It’s cheaper than gas
  • Completely free mod once you have a tune

Summary: +50whp for $2,000

For about $2,000 you can add 50whp to your BRZ, FRS, or GT86 and eliminate the torque drop in the power curve.

Our two favorite mods on the list are headers and a tune. If you are only going to make a few mods, we suggest going with those two. While an intake and cat-back exhaust system still provide solid power gains, the biggest benefit of the other two is the smoothing of the power curve.

A stock BRZ is going to dyno around 160-170whp depending on compression. Adding these mods can bring those power levels to 210-220whp which makes this small car a lot faster. Overall, you can’t beat an extra 50whp on a 2,700lb car, especially for just $2k.

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2 Comments

  1. Perfect, this is what I am searching for; since im planning to track the car. Mostly the torque dip arent noticeable in track, but definitely something to fix.

    On the same note, is there any oil cooler suggestions as per your experience?

    1. Perrin makes a great oil cooler, a bit on the pricier end. Skunk2 is a solid more affordable option.

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