Car tuning
Car tuning

Car tuning

by · automotive expert

Need for Speed

Since we have had cars, car owners have been trying to make them faster. Most manufacturers have been trying to make them more reliable. Cars come from the factory with a bunch of stuff designed to make it run a certain way. Have you ever thought about** what is tuning a car?** How do you make it faster? What are a tuner and a programmer? Exactly, engine tuning and a tuning software.

Tuning is trying to get the right mix of variables for peak engine performance. Back in the day, it was actually quite similar to tuning a musical instrument. You tweak some screws and you`d listen. If it sounded right, you did a good job tuning. And if not, you`re at least will require some help from shrink.

Carburetor work

The whole process mostly meant as tuning a carburetor. The carburetors where the air and the fuel mix before they go into the engine. Too much gas and not enough air make the engine run rich. Too much air and not enough gas makes the engine run lean. So it'll either rev to high or idle or it'll sputter out if it's not tuned right.


The degree to which flaps in carburetor can open and let in air, is determined by a screw. And the chamber where the gas and air mix is also tweakable on a car. A tuneup meant that a mechanic would make sure your timing belt was adjusted properly, your ignition is happening at the right time, and that the right mix of air and fuel is getting in the engine.

The new configuration you meant had to tune the engine to work optimally at this point, thanks to the new hardware. Same thing with adding a blower. You have to tune the engine to get the right air/fuel mix into the engine because you're changing another variable away from how it was set at the factory.

Back in the day

And again, back to the history, particularly in 70`s-80`s.

Manufacturers were tuning down engines to make less horsepower and get better fuel economy. And to stop people from tuning their own cars, they put little caps on top of the carb adjustments. And to make sure the air fuel mix was staying efficient, they used: (E)lectronic (C)ontrol (U)nit.

Early ECUs mostly measured oxygen, going into the engine and coming out. They used signal to control a solenoid that would determine how much the car would open or close and how much fuel would be getting mixed with the air. They're effectively taking the tuning out of the hands of the owner. If you wanted a different air/fuel mix, you had to either trick the computer or reprogram it.

ECU, TCM, PCM … a bunch of letters.

This is when tuning as we now know it started taking shape. It also opened the door for computer-controlled variable valve timing and computer controlled ignition timing. Shocking isn`t?

By the way, an ECU`s is the same thing as an ECM, or an (E)ngine (C)ontrol (M)odule. The ECU really only controlled fuel mix in the early days. But it started becoming more important as fuel injection started getting refined. And later on, manufacturers added (T)ransmission (C)ontrol (M)odules.

But what does PCM mean? They started putting them together with the ECU in the same chip, which makes it a (P)owertrain (C)ontrol (M)odule.

ECU now

But forget all this alphabet soup. Most people now just refer to the whole thing as the ECU. Now, we know that the ECU`s is a little computer that gathers information from sensors placed all around your car. Then it gets sent in from wheel speed sensors, engine sensors, O2 sensors, zero flow sensors, temperature. Oh dear… there's so many of them.

The ECU takes all of it and does millions of calculations every second to determine how to control everything from the air/fuel mix to transmission shift to the engine's redline. The ECU also identifies problems while it's sorting through all that info.

As ECU's became more common, engine and emissions equipment became increasingly electronic and complicated, car manufacturers started to put in diagnostic ports to make it easier to figure out exactly WHY the engine light was on. But there was no industry standard.

So they use whatever kind of port they felt like. To figure out why the lights on, you might have had to connect some pins to the port, or gently caress it, tiny screw on the ECU. Then you'd wait for the warning light to blink out of code. And then you'd look up the fault that that code corresponding to.

Porting stuff

Or maybe you could buy an expensive proprietary scan tool, and/or computer to make things a little easier on yourself. But every manufacturer had their own idea what these ports should look like.

Porting stuff

The government mandated that all cars came with a standardized (O)n (B)oard (D)iagnostic system, so they can better monitor emissions. And keep a car running clean. So from the 1996 model, every car is equipped with a universal OBD-II port.

OBD tuner


But why are we point out on OBD`s? Because an OBD tuner can tell you ALL about the little things going on inside the engine and that can help you tune your car.

We mentioned all the things that go into tuning a car: valve timing, ignition timing, air/fuel ratios and more. And now, these things are determined by a computer. Tuning programs the computer to optimize engine performance by changing any or all of these variables.

Now, because so many things are controlled electronically and valve timing can be varied we can change things like ignition and valve timing without changing hardware and make it better at different RPM. With OBD programmer, we can achieve peak performance from about a fifty RPM range to a 400 RPM window. That's…pretty good.



An OBD-II programmer can also cue you into things that are hurting your performance outside of the tune. If one of your sensors is malfunctioning or clogged it's going to screw up your performance, because the ECU doesn't have an authentic picture of what's going on.

You don't use these OBD sensors to tune in the car. You need a separate computer for that and big brains. But an OBD-II sensor with a good interface will let you know what's going on inside of it from the tune.

Changing engine performance

The spark in the cylinders kind of like a wave. It got more force as it gets going. We wanna make sure we're getting the most force to the crank when we've got the best mechanical advantage. As the speed of the engine changes, the point where this optimization occurs changes as well. And that is why ignition timing can be so important.

In the early days of electronic tuning, people had to figure out what meant what in the ECU coding. So they've changed half the values in the ECU and see if it changed safe fuel. If it didn't, they changed the other half of values and it would change fuel. Then they just keep changing half and half and half again and again until they found the value that affected fuel.

Nowadays, all that legwork`s been done. And it's easier to know what to change your ECU's coding to change what you want in the engines performance.

Other ECU tweak seek out performance without adding physical mods would be raising rev limits. Fiddling with launch control settings and removing undefeatable traction and stability control programs. But don't screw around with these things unless you really know what you're doing.

The people who do know what they're doing are really good at it. You shouldn't tune your engine unless you're a professional engine tuner. If you wanna try around with a car you're not gonna drive, do it as a hobby. There are guys who have been doing it since the early days of ECU and they're still learning stuff.


But what about those chips? They`re claim, they can eat you out an extra 25 or 50 more horsepower without doing anything else. Look…most car companies are factory tuning their cars for optimum performance about a wide powerband.

They want you to have a well performing car. Unless you're adding some hardware like a blower or maybe NOS injection, there is no way you're cranking out an extra 50 horsepower for ECU alone. If you have hardware like intakes, an exhaust, headers or injectors, well, the engine`s gotta be recalibrated and that is where tuning comes in.


Good tuning companies use in cylinder pressure sensors or knock sensors to keep from blowing things up. Good tunes are warranted and tested for thousands of miles and tracks been in garages.

So, that`s what we called auto tuning.


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