Home / Tunes / Subaru WRX / STI Nashville
FA20 / EJ257 · 2015-2024

Subaru WRX / STI tune. Nashville.

The WRX (FA20 turbo) and STI (EJ257 turbo) are two of the most well-documented tuning platforms in the JDM world. Stage 1 alone picks up 50+ wheel hp on stock turbo. Stage 2 with downpipe + intake + intercooler pushes past 380 on the right supporting mods.

Reserve your slot → (615) 730-8654
Same-day · morning drop-off Safe maps, built to last Refundable up to 48h
Stock
268 hp
Stage 1 typical
320+ hp
Stage 2 ceiling
380+ hp

Every Carma tune includes.

Real prices, no dyno-number runaround. Here's what comes with every flash — at no extra charge.

Same-day turnaroundDrop it off in the morning, drive it home tuned by end of day.
Safe maps, built to lastConservative, OEM-protective calibration — tuned for longevity, not just a peak number.
Free octane maps — 91 / 93 / E85Whatever you run at the pump, we load the right map for it.
Free re-flash when you modAdd an intake or bolt-ons later? We update your tune free.
Back to stock anytime, freeDealer visit or resale — we revert it at no charge.
Refundable up to 48 hoursPlans change. Cancel up to 48h before drop-off for a full refund.

What we do for the wrx / sti.

Stage 1 unlocks the FA20 or EJ257 safe envelope on 93 octane. We've mapped Subarus for over a decade — the playbook is mature. Stage 2 with bolt-ons + ethanol blend is well-trodden territory.

Pricing for the subaru wrx / sti.

Stage 1
Safe map · pump gas
$599
Safe pump-gas map. Same-day flash — drop off in the morning, drive it home tuned.
Stage 2
Bolt-ons + supporting mods
By call · scoped
Every Stage 2 scoped by call. Mods + fuel + dyno time priced together.
Custom
Built motor / race fuel
$799+
Mapped from scratch on our dyno. E85, methanol, big SC, built block.
Don't feel it? We'll flash it back — free.

No dyno-number games, no hard sell. Drive it, and if the tune isn't for you, we revert to stock at no charge. That's how confident we are in the map.

Common questions.

WRX vs STI — different tune?

Yes — completely different engines (FA20 in the WRX, EJ257 in the STI through 2021). We tune each as its own platform.

Stock turbo limit?

WRX stock turbo: ~330 wheel hp. STI stock VF48: ~380 wheel hp. Past that, upgraded turbo is the next step.

Is the transmission rated?

STI 6-speed is robust. WRX CVT is the limiting factor on power — TCM tune helps but it's not a built-engine candidate.

How long does the appointment take?

Stage 1: 2 hours. Stage 2 with mods to install: half-day to full day.

Book your Subaru WRX / STI tune.

Drop it off in the morning, drive it home tuned by end of day. 1035 3rd Ave S, Nashville, TN 37210 · Mon–Fri 8 to 5.