Turbocharging Prep & Tuning Guide

One page to guide 2.5T enthusiasts and customers before a tune.
Prevent the usual pitfalls and get a better, faster tuning experience.

View Checklist View Tuning Process

Pre‑Tune Checklist

Confirm these items before scheduling. Mechanical check first — software second.

Fuel system ready
Healthy pump, clean filter, injectors sized for target HP, steady fuel rail pressure under load. Static fuel pressure set to 4 bar.
Ignition setup
Correct heat‑range plugs (Ex. BKR7E), proper gap (0.028" for reference), good coil packs and wiring.
Wastegate setup
Wastegate spring installed, no leaks and bolts properly tightened.
Intake & charge pipes
Tight clamps, correct couplers, proper PCV setup, no vacuum or boost leaks.
Exhaust & O₂
No exhaust leak and wideband (primary O₂) available for logging.
Cooling system
No overheating, properly routed turbo coolant lines, working fans/thermostat, intercooler not heat‑soaked.
Sensors & harness
Upgraded MAP sensor installed, IAT sensor reading properly and tidy harness. (Solid grounds and connectors)
Laptop & internet
Laptop with a good battery life and access to a stable WI-FI network.
Checklist completion 0%

Complete every item before tuning. If any box can’t be checked, address it first — this avoid wasting time.

Ready to book a tuning session

Common Errors That Delay Tuning

Save hours by fixing these before logging.

Vacuum/boost leaks

Smoke‑test the intake manifold and pressure test the charges pipes.

Cheap wastegate

Don't cheap out on the wastegate and invest into a quality brand name, such as Tial, Precision Turbo or Turbosmart.

Wastegate plumbing

Please refer to the installation guide provided with your wastegate and ensure you have a good reference line.

Wrong spark plugs/gap or cheap coil packs

Test out the output of your coil packs with a spark tester, it should be able to produce a spark of at least 12kV.

Wideband not working

Check the fuse for the wideband (primary o2 sensor) and the wiring to the ECU.

Pro Tips

Small tips to prevent issues on the tuning day.

Torque & seal

Use proper clamps, fresh gaskets, and torque to specs — most "mystery" issues are mechanical.

Verify sensor readings

Wideband, MAP, IAT, ECT, etc. If you can’t measure it, we can’t tune it.

Knock sensors

Replace both knock sensors and torque them to 20Nm. The tightening specification affect the function of the knock sensor.

Wideband sensor

Replace the wideband sensor for a genuine Bosch unit.

How the Tuning Process Works

Transparent steps from first message to final map.

  1. Preparation — Complete the checklist and fix DTCs.
  2. Book & Share — Schedule your tuning session and share hardware specs & objectives.
  3. First Flash — Initial base map that match your setup as closely as possible.
    *It can be a rough map depending on your setup, and it is not recommended to daily drive without first running logs.
  4. Initial Logging — Set up the logger, run a first log to validate engine operation at idle.
  5. Data acquisition - Logs of casual driving + accelerations in safe conditions.
  6. Fine tuning — Tune revisions based on your logs until the tune meets our tolerances.
Before the session
  • Build sheet ready: turbocharger specs, WG spring, injectors specs, fuel pump, fuel pressure regulator, intake manifold, etc.
  • Fix hardware first — software can’t compensate for mechanical faults beyond safe limits.
  • Double check the scheduled date and time, we are on the EST timezone.
Book or ask a question

Frequently Asked Questions (FAQ)

Use the fuel you plan to run daily. If mixing (e.g., E30), blend consistently and confirm ethanol content.

*Minimum 91 AKI

At the moment we do not support flex-fuel setup, this feature is still in development.

Yes, an aftermarket clutch is required to handle the extra torque.

09G/DSG users: The TCU will need to be tuned to properly handle the torque.

Yes it is supported, although we strongly recommend doing a DSG swap, as the 09G struggle to handle the extra heat and the torque from forced induction setups.

You can use the stock fuel injectors and MAP sensor to run the engine at idle, and test for leaks before scheduling a tuning session.

Unfortunately, we do not have a specific recommendation as it depends on your goals and budget. It can be an exhausting list, unique to every individual. We cannot build a list for you, although we can give recommendations based on our experience.

For a complete build list, please visit a local performance shop.

Simple and common setups can be done in a day with only a few revisions. Complex builds may require extended logging and revisions that can last days/weeks, depending on the workload and how proactive you are with the logging process.

We support most Bosch EV14 fuel injectors from 550cc and up.

Our recommendation: CPI Injection

After the initial logs, you will be advised on whether it is possible to daily drive your car.

No, we do not offer tuning capabilities to hobbyists/professionals. If you would like to tune on your own, we encourage seeking a standalone engine control unit.

Contact

Interested in our 2.5T tuning solutions or have any questions?
Get in touch with us!

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Session tips
  • Use a stable WI-FI connection.
  • Battery tender on; fans clear; good ventilation. Safety first.
  • Plan extra time in case of issues that could delay tuning.
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