Tuning Strategies & Map Scaling ~8m

Tuning Strategies & Map Scaling

Modifying ECU maps isn’t simply a matter of raising every value. A good tune balances torque, power, fuel and ignition advance while keeping the engine within safe limits. In this module you’ll learn core tuning concepts and how to adjust maps responsibly.

⚙️ Torque, Power & AFR Basics

• Torque is the twisting force produced by the engine. It’s what you feel when accelerating.
• Power is a function of torque and engine speed: Power = Torque × RPM / 5252. More torque or higher RPM equals more power.
• AFR (Air–Fuel Ratio) is the ratio of air to fuel in the combustion mix. For petrol engines, 14.7:1 is stoichiometric; richer mixtures (lower AFR) are used under high load to keep temperatures down.

🎯 Principles of Safe Tuning

1. Start with a baseline: Understand the stock map and how the engine behaves before making changes.
2. Incremental changes: Adjust values by small amounts (5–10 %) instead of large jumps. This reduces risk and makes issues easier to diagnose.
3. Maintain balance: Increase boost? Then adjust fuel and ignition accordingly. Raising one map without compensating others can lead to knock or lean conditions.
4. Respect safety limits: Keep EGTs, lambda and knock within safe ranges. Don’t disable protection maps.
5. Smooth transitions: Avoid sharp spikes or steps in your maps; they cause surging, detonation and poor drivability.
6. Test & verify: Use simulations and datalogging to see how changes affect torque, AFR and boost before writing to a real ECU.

✍️ Scaling Maps

When scaling a map:

• Multiply by a factor to increase output uniformly (e.g., +5 % torque across the table).
• Add or subtract a value to shift the whole map up or down (e.g., adding 2° to ignition timing in a specific region).
• Scale by row or column to target certain RPM or load zones rather than the entire map.

The Map Scale Adjuster tool on this site can perform percentage or additive scaling for you. After scaling, inspect the resulting values for smoothness and re‑simulate the effect.

🧪 Safe Tuning Workflow

Use this workflow each time you approach a new ECU:

1. 1 Analyse the stock map
   Identify peak torque regions and factory limits.
2. 2 Plan adjustments
   Decide where to add power and by how much based on hardware capability.
3. 3 Scale incrementally
   Use a 5–10 % increase in key areas (e.g., mid‑range torque).
4. 4 Smooth the map
   Ensure there are no abrupt steps or spikes.
5. 5 Simulate & log
   Run the tune through a simulator or datalogging session to check AFR, EGT and knock.
6. 6 Refine
   Adjust based on results and retest until you achieve balanced performance.

✅ Key Takeaways

• Torque and power are related but not identical; aim for balanced increases.
• AFR and ignition advance must be considered alongside boost and fuel when increasing power.
• Make small, incremental changes and smooth your maps to avoid drivability issues.
• Use tools like the Map Scale Adjuster to apply uniform scaling and always verify results with simulation or logging.

In the next module you’ll learn how to create and smooth custom maps using our in‑browser tools.