The Quick Answer
A VAST tune is iterative—we gradually increase performance through datalogging and retuning until your car is making the maximum power it can safely produce.
What You’ll Need
- A Windows laptop — Required for datalogging and flashing new tunes (compatible with Windows 7, 8, 10, and 11). We offer a rental for those who don’t own a Windows laptop.
- Mac users: You can run a virtual Windows machine using a program like Parallels
- VAG-COM cable — Included with your order
The Tuning Process
Step 1: Setup
After purchasing a tune through the Tune Builder, you’ll receive:
- Your ECU, pre-flashed with a base tune
- A VAG-COM cable
- A .zip file containing setup instructions and all necessary software
Simply follow the instructions in the .zip file to set up your laptop, then plug the VAG-COM cable into your computer and your car’s OBDII port.
Step 2: The Base Tune
The base tune is a conservative starting point. It’s designed to let you drive the car safely while we verify everything is working correctly—without risk of damaging a component if there’s an underlying mechanical issue.
Step 3: First Datalog (Diagnostic)
Your first datalog serves as a diagnostic overview of your car. We’ll check all sensors, look for air leaks, and identify any injector problems.
What to do:
- Drive normally—no aggressive throttle needed
- Collect a 20-30 minute log
- Include periods of idling
Step 4: Performance Tuning Begins
If no problems are found, you’ll receive a new tune with increased boost. Now we need to see how the car responds under load.
What to do:
- Collect another ~20 minute log
- Include periods of full throttle
- Perform a full-throttle pull from 3000 RPM to redline in 3rd gear
Step 5: Repeat Until Fully Tuned
We’ll review each log and send updated tunes. This process continues—log, review, retune—until your car is making the maximum power it can safely produce.
Why Iterative Tuning?
Every car is different. By tuning iteratively through datalogs, we can:
- Catch mechanical issues before they become expensive problems
- Safely push your car to its actual limits—not a generic estimate
- Ensure the tune is optimized for your specific hardware and conditions