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GTS
Audi B5 S4 / C5 A6 2.7T Stage 1/2 Tune (APB/BEL)
USD $299.99
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GTS calibrations are developed for vehicles with all factory emissions equipment intact and functional. Features that remove or raise factory speed and rev limits are intended for closed-course use only. These calibrations are not CARB-certified, and the customer is responsible for compliance with all applicable laws, including the emissions and inspection requirements of their jurisdiction.
The GTS difference: a real tune built for your exact car, not one calibration with three names on a dropdown. We’ve got the injectors and turbo kits to back it up, and the in-house support to actually run it. Tuning VW, Audi & Porsche since 2010.
Why we're different ›
STAGE 1: 320 HP / 350 LB-FT
STAGE 2: 330 HP / 375 LB-FT
Fits
Audi B5 S4 2.7T biturbo, engine codes APB and BEL, and the same 2.7T biturbo in the C5 A6 and allroad. This listing is for the stock K03 turbos. Pick your stage in the dropdown. The calibration is written for your car and your hardware. Not sure which code you have? Find your engine code in two minutes. Upgraded turbos, K04s or a big turbo, have their own listing at Stage 3 and Stage 4 B5 S4.
What the tune does
Written for 93 octane / 98 RON and adapts to 91 / 95. Stage 1 runs 16 psi on the stock K03s and makes 320 hp and 350 lb-ft with no parts on the car. Stage 2 runs 20 psi and goes to 330 hp and 375 lb-ft once upgraded downpipes are on. Both: lag removed, speed limiter removed, rev limit raised to 7000, and better mileage when you are not in it. Tested on the street and the track to be smooth yet powerful.
Stages on this listing
| Stage | Power | Boost | Needs | Price |
|---|---|---|---|---|
| Stage 1 | 320 hp / 350 lb-ft | 16 psi | stock car, no parts | $299.99 |
| Stage 2 | 330 hp / 375 lb-ft | 20 psi | upgraded downpipes | $399.99 |
| Stage 3 K04 | custom, built for your turbo | custom | plain jane (PJ) or hybrid K04 turbos, 550cc or bigger injectors, 85mm Hitachi MAF, turbo-back exhaust, front mount intercooler, upgraded diverter valve | $599.99 |
| Stage 4 Big Turbo | custom, built for your turbo | custom | big or single turbo, 630cc or bigger injectors, 3 inch MAF housing, turbo-back exhaust, front mount intercooler, upgraded diverter valve | $699.99 |
Start at Stage 1 if the car is stock and move up when the hardware changes. PJ K04s, K04 hybrids and big turbo builds are on the Stage 3 and Stage 4 listing.
What you need on the car
- Stage 1: nothing. Stage 1 runs on a completely stock car. A turbo-back exhaust, an upgraded diverter valve and an upgraded intercooler are all recommended, and none of them are needed.
- Stage 2: upgraded downpipes. Nothing else is required, and the same exhaust, diverter valve and intercooler are recommended.
- Bigger turbos: PJ K04s, K04 hybrids or a big turbo need the custom calibration on the Stage 3 and Stage 4 listing.
After you order
- Order. Pick your stage, then choose Remote Tuning. A GTS cable ships with your order for a one-time $40 and it is yours to keep for every tune after this one.
- Read. Plug the cable into the OBD port and a Windows laptop, Windows 10 or later. An Intel Mac on Boot Camp works too. Our software identifies your ECU and saves your original calibration before anything is written.
- Flash. We build the calibration for your car, your hardware and your fuel. You get a message the moment it is ready, and you flash it yourself in your driveway in about ten minutes.
- Log. Drive, log, send. If anything wants adjusting we adjust it and you flash again. Revisions usually come back the same day, and within 72 hours at the outside.
Prefer to mail the ECU in? Mail-in is free within the USA and Canada. We flash it on the bench and send it back in two to three days. Local? An OBD flash at the shop takes 10 to 15 minutes. How remote tuning works, start to finish.
Options explained
- Stage: pick from the table above. Stage 1 for a stock car, Stage 2 once upgraded downpipes are on.
- Soft launch control: included free.
- Hard launch control (2-step): an add-on, for off-road and competition use.
- IMMO delete: removes the immobilizer check so a swapped or spare ECU runs without the key and cluster handshake.
- Mail or Remote: remote is what most owners pick. Mail-in if you would rather not touch a laptop. Dealer if a shop is doing the install for you, and we deal with them directly.
Why GTS
Tuning since 2010, as Gonzo Tuning first and as GTS since 2013. Every calibration is written in house and the flashing tool is ours, not a rebadged package, and we never ask for remote access to your computer. Your original calibration is kept, so the car can go back to stock whenever you want it to. Reflashes carry a one-year warranty, and if you are not happy within 30 days you can go back to stock for a refund under our return policy. Support in English and Spanish.
Ordering from Canada or overseas
Canadian owners have ordered from us since 2014 and Canada is our second-largest market. The tune is delivered digitally, the cable is delivered within Canada with no customs and no import fees, we accept Canadian cards, and return shipping on a mail-in ECU is free. Anywhere else in the world, remote tuning needs the car, the cable and an internet connection, nothing else. We have tuned cars in Australia, Germany, the United Kingdom, the Netherlands, New Zealand, Hungary, Puerto Rico, Panama, Costa Rica and Barbados.