Stage 1
Stage 1 · Petrol · 4.2 Biturbo 450hp
Audi RS6 4.2 V8 Turbo Stage 1 file Bosch HW 0261208728 · 4D1907558F · SW 370934
Audi RS6 4.2 V8 Turbo Turbo Petrol 331 kW (450 HP) Stage 12003, Turbo petrol, 331 kW (450 hp)
450 → 520 HP +70 HP +165 Nm 16% more power
Calibrated ECU file for 0261208728 (SW 370934). Checksum-corrected, ready to flash. Delivered instantly via secure download after payment.
Performance projection
Matched engine: 4.2 Biturbo 450hp, BCY, 4.2L, Petrol. Engine #662 in our gains database.
- Power
- 520 HP+70 HP from 450
- Torque
- 725 Nm+165 Nm from 560
- Fuel economy
- −8 %−12% full load
Real data from Gains API. Dyno curve = typical ECU-family projection. Final gains depend on fuel, altitude, wear.
How it works
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Read your ECU
With KESS, KTAG, AutoTuner or Flex. Keep the read: it is your way back.
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Match the numbers
Your read must show hardware 0261208728 and software 370934.
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Pay and download
Card, Apple Pay or Google Pay. The file is in your account straight away.
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Write it and drive
Write it back the way you read it. Not right for your car? We correct it free.
What the car needs
Required modifications: Stage 1, Petrol.
Hardware
- No hardware changes required: runs on completely stock hardware
Software / calibration
- Boost / load targets optimised within factory hardware limits
- Ignition advance refined for the running fuel grade
- Throttle response and torque request remapped
- Factory safeties (knock, lambda, EGT) preserved
Stage 1 is a software-only calibration. Compatible with stock turbo, injectors, intercooler, exhaust and clutch.
Vehicle & ECU specifications
Exact vehicle, engine and ECU identifiers this calibration file is written for. Cross-check against your ECU before flashing.
| Vehicle make | Audi |
|---|---|
| Vehicle model | Rs6 |
| Model year | 2003 |
| Displacement | 4.2 L |
| Fuel / Induction | Petrol |
| Factory power | 331 kW (450 HP) |
| ECU manufacturer | Bosch |
| ECU ID | 4D1907558F |
| ECU hardware | 0261208728 |
| ECU software | 370934 |
| Calibration stage | Stage 1 |
| Cylinder capacity | 4172 CC |
| Compression ratio | 9,3 : 1 |
| Bore × Stroke | 84,5 X 93,0 mm |
| OEM engine code | BCY |
| File format | BIN / ORI |
| Checksum | Pre-corrected (ready to flash) |
| Delivery | Instant download after payment |
Engine performance matrix
Power, torque and fuel-economy figures for every tuning stage on this engine, sourced from the tuning-database Gains API. Values are healthy-engine crank numbers; real on-road gains vary with fuel, altitude and mechanical condition.
| Stage | Power | Torque | Δ HP | Δ Nm |
|---|---|---|---|---|
| Original / Factory | 450 HP | 560 Nm | — | — |
| Stage 1 | 520 HP | 725 Nm | +70 (15.6%) | +165 |
| Stage 2 | 622 HP | 964 Nm | +172 (38.2%) | +404 |
| Stage 3 | 743 HP | 1012 Nm | +293 (65.1%) | +452 |
| Stage 4 | 878 HP | 1063 Nm | +428 (95.1%) | +503 |
About this calibration file
The Stage 1 calibration for the 2003 Audi Rs6 4.2L Petrol is a drop-in remap that works on completely stock hardware — no turbo, injector, intercooler or fuel-system upgrades required. Injection timing, boost targets, rail-pressure limits and torque maps are rebalanced to extract the safe headroom the OEM leaves untouched for fleet-fuel tolerance, altitude margin and warranty buffer.
This file matches a Bosch ECU with hardware number 0261208728 and software version 370934. Verify both identifiers in your flashing tool before writing — an ID mismatch is the most common cause of a bricked ECU. If you are unsure, upload a read of your original file via the file-request wizard and our engineers will confirm compatibility before you flash.
Projected output on a healthy, stock-hardware example of this engine: 520 HP and 725 Nm at the crank — a gain of +70 HP (16%) and +165 Nm over the factory 450 HP / 560 Nm baseline. These numbers are sourced from our Vehicle Performance Database, which aggregates dyno results across this engine family. Real-world gains depend on fuel grade, ambient temperature, mechanical condition and intake/exhaust state.
The file is delivered as a ready-to-flash BIN (and ORI backup where applicable) compatible with all major tools — KESS V2/V3, KTAG, AutoTuner, CMDFlash, Dimsport New Genius, MPPS, Flex, BFlash, PCMFlash, MMFlash — via OBD, bench or boot-mode as supported by your ECU family. Checksums are pre-computed and verified; no additional checksum tool is required. All files include a free revision if post-flash logs reveal a fuelling, boost or EGT issue.
Frequently asked questions
0261208728 (Bosch) listed in the specifications. Read your ECU with any supported tool (KESS, KTAG, AutoTuner, CMD, etc.) and compare the hardware + software numbers against the ones on this page. If they match exactly, the file is a direct fit. If you're not 100% sure, upload your original read via the file-request wizard and our engineers will confirm within minutes — no cost, no obligation.Product details
This product contains a calibrated Stage1 tuning file for Audi RS6 4.2 V8 Turbo 2003 Turbo-Benzin 331KW with Bosch 0261208728 and software ID 4D1907558F (Bosch software number 370934 ( 1037370934 )). The base stock vehicle for this calibration has a factory output of around 331 kW (~450 HP). This Stage 1 calibration is designed for stock hardware, offering a safe and reliable increase in power and torque for daily use.
All ECU tuning files from TUNING-DATABASE are prepared for professional use. They are useful whenever you search by ECU ID, hardware or software number such as 0261208728, 4D1907558F, 370934 (1037 + SW code). Use this file for diagnostics, cloning, recovery or as a base for custom remapping.
38C88B19 D3193208 5A1A483E F3D653DD 3AD0543D 69E20A4B DFA59232 617F731B