Audi S3 8YStage 1 to Stage 3 tuning guide

What we'd do

Which S3 you have decides everything. The S3 sold new in Israel today is the 333 PS facelift, and RacingLine says that engine computer cannot yet be tuned the traditional way. For that car the realistic option is RacingLine's PCM box ($980.99), which claims 393 PS and 491 Nm and comes with a free upgrade to a full file later. RacingLine is sold here through Top RPM.

On a 2020–2024 car (310 PS) our pick is APR. Its Stage 1 claims 398 hp on 95 and 405 hp on 98 for $526.95, and since early 2025 it gives full torque without a gearbox tune. The sweet spot is APR's Stage 2 with the filter kept: its intake and intercooler take the claims to 410 hp on 95 and 416 hp on 98. Unitronic says the factory intercooler quickly heat soaks, which in an Israeli summer matters more than the headline figure.

Order: check which engine and gearbox computers the car has, then the software, then the intercooler (APR $958.95 or Wagner €999 before VAT), then the intake (APR $403.95). With APR's parts that is about $1,890 in list prices before shipping, tax and fitting. Skip the downpipe: the only one we found that is ECE-approved and keeps the filter is HJS's at €3,334.98. Skip Stage 3 unless you accept approval for a new turbo, oil changes at half the factory interval (APR's advice) and a gearbox tune.

The one thing to check before paying is the gearbox computer. Unitronic says some 2022 and many 2023-on cars have a locked unit that can't be flashed through the port; it now sells an unlocked replacement, and RacingLine dealers can unlock it with a cable.

Tuning it in Israel

New price in Israel

The importer's price list no. 089, dated 25 October 2026 (audi.co.il): S3 Sportback TFSI quattro ₪440,700 and S3 Sedan ₪444,700, including VAT, plus a ₪5,499 licence fee (₪446,199 and ₪450,199). These are the 333 PS facelift cars, which can't be flashed yet (see Stage 1).

Parts from abroad

At the Bank of Israel representative rate of 26 October 2026 ($1 = ₪3.078, €1 = ₪3.4462), APR's intercooler ($958.95) is ₪2,952. Above $75 it carries 18% VAT and purchase tax, about 40.66% combined (our import guide): ₪2,952 × 1.4066 = about ₪4,152. Wagner's (€999 before VAT) is ₪3,443, about ₪4,843 landed, and APR's intake ($403.95) is ₪1,243, about ₪1,749. RacingLine's PCM box ($980.99) comes to ₪3,019, about ₪4,247 if it is taxed at the same rate. All before shipping, which is taxed too.

Fuel

Audi rates the facelift for 98. APR publishes both fuels: Stage 1 398 hp on 95 and 405 on 98, Stage 2 410 and 416. IE's Stage 1 is 385 and 397. So on this engine 98 is worth 6–12 hp, and a 95 file is a sound choice if 98 isn't on your routes (95 vs 98 after a tune). Ethanol files and port-injection kits don't apply: ethanol blends aren't sold at Israeli stations.

Regulation 380 and the test

Regulation 380 requires a permit for a special exhaust, special wheels and accessories the manufacturer didn't fit, and the Road Safety Authority reads it as covering engine software too (how approval works). Parts with approval papers are the easiest to record: Wagner's intercooler has a German parts certificate, and the HJS downpipe and Akrapovič's Evolution exhaust are ECE-approved for filter cars. A filter delete or race downpipe isn't road legal, and passing the annual test doesn't make an unapproved change legal.

Where to get it done

RacingLine, Integrated Engineering and Milltek list Top RPM (Holon). APR and Remus list PIT-STOP (Holon). REVO lists Full Boost (Holon), AVTuning (Haifa) and CH Performance (Peki'in), and Unitronic lists Max Tuning (Petah Tikva). These are the brands' own lists, checked October 2026; we have no link with any of them.

Prices and rules checked 2026-10-28.

Also useful: tuning shops in Israel, the import tax calculator and the annual test checklist.

What owners ask

Can I tune the 2024-on facelift S3 (333 PS)?

Not with a normal flash yet. A facelift owner asked the forum whether anyone runs a JB4 on it, because the flash files cover the earlier car. RacingLine says the late-2024-on version of this engine cannot yet be tuned by the traditional methods, and names the S3 8Y.5. Its answer is the PCM plug-in box, which it says installs and comes off without leaving a physical or digital trace, with a free upgrade to its full ECU file once one exists.

Sources: audi-sport.net: S3 8Y facelift, anyone using JB4? (2025), RacingLine: PCM tuning for 2024+ 2.0 TSI

Is the RacingLine PCM box worth it?

An S3 8Y owner had the PCM fitted to a stock 310 PS car by a listed RacingLine installer. The shop couldn't get the car to run on its dyno, so he had no figures, but on a short drive it felt a clear improvement, with fuel economy much worse. On a facelift car the box is the only RacingLine option. On a 2020–2024 car a flash file costs less and claims more: APR's Stage 1 is $526.95 for 398 hp on 95.

Sources: audi-sport.net: Racingline PCM (2025), RacingLine: PCM tuning for 2024+ 2.0 TSI

Should I run 98 or 99 in my S3?

An S3 8Y owner who had always used supermarket 95 asked whether he should switch. Replies said the fuel flap lists 98 first and 95 as the fallback, and most owners there run 98 or 99. Once tuned the difference shows in the published figures: APR's Stage 1 claims 398 hp on 95 and 405 hp on 98. In Israel 98 is sold only at some stations and its price isn't capped, so choose the file for the fuel you will actually buy.

Sources: audi-sport.net: Is the S3 designed for V power etc? (2024)

My 2023 S3's gearbox can't be flashed. What now?

Many later DQ381 gearboxes have a locked "401" gearbox computer. In May 2025 Unitronic released an unlocked replacement unit for the Golf GTI and R Mk8 and the S3 8Y, which lets them run its gearbox software. RacingLine dealers can now unlock the DQ381 G2 with its CommsLink cable, in minutes and with no hardware change. Its gearbox tune raises clutch pressure up to 19 bar. Since APR's Stage 1 gives full torque without a gearbox tune, you can do the engine first.

Sources: Unitronic: DQ381.2 unlocked TCU (May 2025), RacingLine: DQ381 G2 and ZF8 unlock, RacingLine: DSG software

Will a remap void the warranty on a new S3?

Owners asked this as soon as the 8Y arrived, and the replies were blunt: remap a new car and be ready to pay for an engine yourself. Audi's UK warranty terms exclude damage caused by parts, components or software Audi hasn't authorised, and damage caused by modifications. The Israeli importer's terms may differ, so ask in writing before you tune a car under warranty. A removable plug-in box is the usual compromise.

Sources: audi-sport.net: Remap, any experience or recommendations? (S3 8Y, 2021), Audi UK warranty terms (PDF)