Stage 1
Stage 1 · Petrol · 4.2 FSI V8 420hp
Audi RS4 4.2 V8 Stage 1 file Bosch HW 0261S02357 · 8E1907560 · SW 381967
Audi RS4 4.2 V8 Petrol 308.9 kW (420 HP) Stage 12009, Petrol, 308.9 kW (420 hp)
420 → 440 HP +20 HP +25 Nm 5% more power
Calibrated ECU file for 0261S02357 (SW 381967). Checksum-corrected, ready to flash. Delivered instantly via secure download after payment.
Performance projection
Matched engine: 4.2 FSI V8 420hp, BNS, 4.2L, Petrol. Engine #655 in our gains database.
- Power
- 440 HP+20 HP from 420
- Torque
- 455 Nm+25 Nm from 430
- 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 0261S02357 and software 381967.
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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 | Rs4 |
| Model year | 2009 |
| Displacement | 4.2 L |
| Fuel / Induction | Petrol |
| Factory power | 308.9 kW (420 HP) |
| ECU manufacturer | Bosch |
| ECU hardware | 0261S02357 |
| ECU software | 381967 |
| Calibration stage | Stage 1 |
| Cylinder capacity | 4163 CC |
| Compression ratio | 12,5 : 1 |
| Bore × Stroke | 84,5 X 92,8 mm |
| OEM engine code | BNS |
| 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 | 420 HP | 430 Nm | — | — |
| Stage 1 | 440 HP | 455 Nm | +20 (4.8%) | +25 |
| Stage 2 | 455 HP | 470 Nm | +35 (8.3%) | +40 |
| Stage 3 | 693 HP | 667 Nm | +273 (65%) | +237 |
| Stage 4 | 819 HP | 796 Nm | +399 (95%) | +366 |
About this calibration file
The Stage 1 calibration for the 2009 Audi Rs4 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 0261S02357 and software version 381967. 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: 440 HP and 455 Nm at the crank — a gain of +20 HP (5%) and +25 Nm over the factory 420 HP / 430 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
0261S02357 (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 RS4 4.2 V8 2009 Benzin 308.9KW with Bosch 0261S02357 and software ID 8E1907560 (Bosch software number 381967 ( 1037381967 )). The base stock vehicle for this calibration has a factory output of around 308.9 kW (~420 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 0261S02357, 8E1907560, 381967 (1037 + SW code). Use this file for diagnostics, cloning, recovery or as a base for custom remapping.
7C148441 3EE4ED71 CE22D8FD 5552829D D02486B0 E6C28086 666ACADA 4A054D47