All topics

Start here Video library

Getting started

The method: stock to final Your first session, step by step Troubleshooting

Engine & fuel

VE and speed-density fuelling Lambda, AFR and target mixtures Injector scaling and dead time Fuel system capacity E85 and the stoich setting

Spark & knock

Ignition timing and MBT Knock, knock sensors and false knock

Boost, heat & limits

Boost control and wastegates Heat: IAT, EGT, coolant and protection Mechanical limits

Reading results

Reading a dyno sheet and log Correction factors and fair comparisons

Reference

Same concept, different names What real software has that this does not (yet)

Learn

Learn dyno tuning and ECU tuning on a free virtual dyno

The fundamentals of engine tuning, written for beginners, next to a browser dyno where you can practise every one of them on a fictional car: edit the VE, lambda, ignition and boost tables, pull the car, read the logs, and see the consequences, up to a broken engine.

ECU tuning is the job of telling the engine computer the truth about the engine: how much air each cylinder takes in, how much fuel that needs, when to fire the spark, and how much boost to allow. A dyno holds the car at full load while you measure power, mixture, knock and temperatures, change one table at a time, and check the result. These pages explain each table and each signal in plain language and in the physics, with the same names your tuning software uses. The app lets you do it: four fictional cars, real-time or instant pulls, logs, diagnostics that explain what went wrong, and engine damage when you get it wrong. Free, no account, nothing leaves your browser.

Start here.

Three pages are the manual: the method, your first session step by step, and what to do when a run looks wrong.

Start your first session →or read the method first

1. The method: stock to finalA fixed order of stages, each assuming the one before it is right. One variable per run, the same conditions every run, deterministic signals first and the knock counter last.2. Your first session, step by stepBaseline, one part, fuel, timing, finish: the whole loop on one car using the app's own controls. About twenty pulls.3. TroubleshootingBy what you see on screen: what it usually means, what to check in order, what to do, and what not to do.

Engine & fuel

VE and speed-density fuellingThe VE table is the ECU's model of how much air gets into each cylinder. Everything about fuel starts here.Lambda, AFR and target mixturesλ is the mixture relative to stoichiometric. It is the same number on every fuel, which is why tuners think in λ.Injector scaling and dead timeThe ECU turns fuel mass into milliseconds using the injector flow rate and dead time. If those lie, everything lies.Fuel system capacityPump, regulator and injectors together set how much fuel you can actually deliver. Boost and E85 eat capacity fast.E85 and the stoich settingSame λ targets, much more fuel, lots of knock margin, cooler charge. The ECU must know which fuel is in the tank.

Spark & knock

Ignition timing and MBTAdvance the spark until torque stops rising. That point is MBT; past it you add pressure and knock risk for nothing.Knock, knock sensors and false knockDetonation is the end gas exploding before the flame reaches it. The sensor hears it; the threshold decides what counts.

Boost, heat & limits

Boost control and wastegatesThe spring sets minimum boost. The solenoid hides pressure from the gate to raise it. Spool, creep and altitude are the surprises.Heat: IAT, EGT, coolant and protectionHeat is the common currency of engine damage. The trims and protection tables exist to spend less of it.Mechanical limitsRods, bearings, valvetrain, head gasket and turbo each have a limit. Tuning finds them if you let it.

Reading results

Reading a dyno sheet and logA power curve is torque times rpm. The log is where the reasons live.Correction factors and fair comparisonsSAE correction normalises the air, not the risk. Compare like with like.

Reference

Same concept, different namesEvery tuning package names the same tables differently. The physics underneath is identical.What real software has that this does not (yet)The simulator keeps the fundamentals and leaves out features that would hide them. Expect these in real tools.

Video library

Outside explanations from working tuners, by section. Each section pairs with a topic above.

Full overview

A whole dyno session from a cold start to a finished map. Watch this before your first session.

How to tune a car: basics to a full dyno sessionJimmy Oakes · YouTube Getting it dyno tuned, flat shift, boost by gear and engine protection (R5 for R35, EP4)Haltech · YouTube

Volumetric efficiency

What the VE table really is and why fuel starts there.

If you understand volumetric efficiency you understand enginesdriving 4 answers · YouTube Tuning with volumetric efficiency and other VE fun factsHaltech · YouTube

Lambda and AFR

Rich, lean, stoich: what the mixture does to power and heat.

Do you want a lean or rich AFR? Fuel vs powerHigh Performance Academy · YouTube Lean vs rich: how fuel mixture really affects power (dyno tested)PyroPerformancePNW · YouTube Mythbusting: which is more important, air-fuel ratio or ignition timing?Haltech · YouTube ECU tuning: what you need to knowBlackthumb · YouTube

Ignition timing and knock

MBT, the knock limit, and the difference between knock and pre-ignition.

A detailed overview of knock and pre-ignition (Boost School 7)driving 4 answers · YouTube 25° of ignition timing gave us max power. Why?High Performance Academy · YouTube

Boost

Wastegates, solenoids and how the ECU controls manifold pressure.

All boost control setups explained (Boost School 3)driving 4 answers · YouTube

Then do it.

Reading explains the table; the dyno teaches it. Pick a car, make a baseline pull and correct the fuel from the wideband, the way a tuner does.

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