1. Tuning Course: Introduction, Goals, Limitations

Tuning: Why bother?

The rise of electronic engine management allows for the running conditions of an engine to be rapidly and precisely adjusted.  Before we talk about anything super technical, it’s worth examining some really basic stuff like, “why should we bother tuning a car in the first place?”  “What can we reasonably hope to accomplish?”

Sometimes we start with an engine that’s running acceptably but we want to slightly change how it operates to achieve our goals.  Sometimes we start with an engine that doesn’t run at all because it is so different from the original system that was running that we have to tune it for it to run acceptably.  Regardless of whether adjustments are made out of necessity or desire, the answer to this “why bother” question is simple: in a word, it is OPTIMIZATION.  Tuning allows us to make the most out of the engine that we have.

What Tuning ISN’T

Tuning cars is often very misunderstood, especially by people who do not do it.  There is no magic involved.  You cannot wave a magic wand and violate the laws of physics in the name of making horsepower.  You are dealing with a computer system that responds to sensors in a predictable way.

There is one golden rule (which I think has its origins in a completely different realm) which applies here:

Garbage In, Garbage Out.

As a tuner, you can only work with what you are given.   This may seem so obvious that it is a waste of time to even say it.  Trust me.  It isn’t.  It’s critical.  And at some point if you mess around with tuning vehicles long enough, you will get so focused on the knobs and buttons available to turn on your computer that you will forget about the mechanical system you are controlling.

  • Changing a computer program can’t fix mechanical issues.
  • Changing a computer program can’t fix electrical issues.
  • Changing a computer program can’t make more air enter an engine than it can mechanically pump
  • Changing a computer program can’t make more fuel flow through pumps/injectors than they can mechanically pump
  • Bottom line: You can’t make pigs fly by pushing buttons.  The physical motor you are working with will define what you do on the computer.

Tuning Possibilities

So if we are inherently limited by the physical engine that we are dealing with, what CAN we typically accomplish with tuning?

Typically, we can:

  • Increase power / torque output of the engine
  • Increase efficiency / decrease fuel consumption
  • Decrease noxious emissions (Carbon Dioxide/CO2, hydrocarbons/HC, Carbon Monoxide/CO, Nitrous oxide/N2O, Nitrogen Oxides/NOx)
  • Control NVH (Noise – Vibration – Harshness)
  • Decrease stress on mechanical components / prevent damage to mechanical components
  • Many of these goals require different operating conditions making it impossible to do all of them at once! 


Tuning isn’t magic.  Modifying electronic engine control systems lets you get the most out of the physical system that you’re working with.  Through tuning, you can choose how to operate an engine in order to achieve the goals that are most important to you, making the compromises you want to make.  The goal of this course is going to be to teach you to use a calculator/simple math and data logging combined with an understanding of underlying processes to make targeted and appropriate changes in order to achieve the operating conditions you desire for your engine.