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Inside the DEFI Motorsports workshop

AudiIn-shop

Audi A3 tuning

2004–2018 · 7 supported configurations

1

Your vehicle

Start here — this choice sets everything below it. The engine controller changes between model years even when the badge does not, so each of these is a different license at a different price.

7 of 7 configurations

2

Transmission

Choose your year and engine first.

3

Fuel you will run

Pick a transmission first.

4

What is on the car

Choose a fuel first.

5

How it reaches your car

Declare your modifications first.

6

Calibrate the transmission too

Optional

Declare your modifications first.

In plain terms

What actually gets rewritten

“Custom tune” is a phrase that can mean anything, which is why we would rather itemize it. This is the scope of the work on a Audi A3 — and several of these lines are sold as separate add-ons elsewhere.

If a behavior you care about is not on this list, ask before you order. If it cannot be changed on your controller, we say so — that is cheaper for both of us than finding out after.

On every calibration

Fuelling and spark
The fuel and ignition tables rewritten for the fuel you declared, verified against knock on every revision.
Torque management
The factory torque limits that blunt response, reshaped deliberately rather than crudely zeroed out.
Throttle mapping
Pedal position to throttle angle, remapped so the car does what your foot actually asked.
Rev and speed limiters
Moved deliberately, within what the rotating hardware and the tires are rated for.
Cooling fan strategy
Fans brought in earlier and harder. Heat is the tax on every additional horsepower, so it is managed, not ignored.

On this engine

Derived from what is actually fitted to this vehicle — this list changes from platform to platform.

Boost control
Boost targets, wastegate or bypass strategy, and overboost protection — where the added power actually lives.

If you add the transmission calibration

Optional, priced in the configurator above.

Shift schedule
Shift points re-planned against the new torque curve instead of the factory one it no longer has.
Line pressure and shift firmness
Clamping raised to carry the added torque — slip under power is how automatics die.
Torque converter lockup
Lockup strategy set for how the car is actually driven, not for a fuel-economy test cycle.

Why this platform is tuned in the shop

Custom Dyno Tune, in Corona

The RTD4 cannot connect to the Audi A3, so the car comes to Corona, goes on the Mainline ProHub, and is flashed with our own interface. We are not going to sell you a device that will not talk to your car.

$500 tuning + $350 dyno session + licensing — from $950 on this platform.

Tell me when this changes

Platforms move onto the delivery network as the calibration vendor adds them. If the A3 does, you will hear from us the week it happens.

A vehicle bolted to the hubs of the Mainline ProHub dyno at DEFI Motorsports

Before you decide

Asked on every one of these

The answers that cost us sales, kept on the page anyway.

All the questions

Longer answers: how dyno numbers get inflated.

Something specific to your car? (951) 405-4465 — a two-minute call beats a form.

Can you ship a tune for my car?
For 285 of the 775 vehicles in our catalog, yes. The rest are supported only as in-shop work because their ECMs cannot be reached over the Tune Delivery Network. Search your vehicle and the page states which applies before you buy.
Why does a hub dyno matter?
Because a roller dyno measures power after it has passed through the tire, so tire compound, pressure and temperature move the number. Our Mainline ProHub bolts to the hubs, which removes that variable and makes results repeatable between visits. Repeatability is the only property that makes a before-and-after comparison mean anything.
Do I get the full sheet?
Always, including runs we were not happy with. Cropping to the peak is how the industry hides work it does not want compared.
Will my car stay smog-legal?
No. Calibration alters emissions-related engine management. Our work is sold for off-road and competition use. We would rather you hear that here than at a testing station.