- Since we've 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.
So how do you make it faster?
Tuning!
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,
it mostly meant tuning a carburetor.
The carburetor's where the air and the fuel mix
before they go into the engine.
Too much gas and not enough air makes the engine run rich.
Too much air and not enough gas makes the engine run lean.
So it'll either rev too high or idle or it'll sputter out
if it's not tuned right.
The choke, wait a minute.
We'll talk about carburetors in a different episode.
We're talking about tuning,
the degree to which these flaps 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.
We looked at torque curves before.
An engine performs best right here.
We've also talked about cams, and lifters, and push rods.
But back in the day, if you wanted to change this peak,
you had to change out some hardware.
And essentially,
you're moving the peak maybe from here to here.
This new configuration meant you 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.
But even when you're making your engine perform better,
you're tuning it for this optimum spot
at one place on the curve.
You couldn't really do much about performance
in these red ranges or these.
Then something happened in late 70s and early 80s.
Manufacturers were tuning down engines to make
less horsepower and get better fuel economy.
And to stop people from tuning your own cars,
they put these little caps on top of the carb adjustments.
And make sure the air fuel mix was staying efficient.
They use E, C, Us.
Early ECUs mostly measured oxygen,
going into the engine and coming out.
They used this signal to control a solenoid
that would determine how much the carb would open or close
and how much fuel would be getting next with the air.
They were 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.
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.
What?
By the way, the ECU's the same thing as an ECM,
or an engine control module.
The ECU really only controlled fuel mix in the early days.
But it started becoming more important as fuel injection
started getting refined.
Later on, manufacturers added transmission control modules.
Eventually, they started putting them together with ECU
in the same chip,
which makes a powertrain control module.
But forget all these alphabet soup.
Most people now just refer to the whole thing
as the ECU.
Now, we know that the ECU's 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, there's so many sensors.
Relax.
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 becoming more common,
engine and emissions equipment became
increasingly electronic and complicated,
car manufacturers started putting diagnostic ports
to make it easier to figure out exactly why
the engine light was on.
But there was no industry standard.
So they used whatever kind of port they felt like.
To figure out why the light's on,
you might 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 a code.
And then you'd look up the fault
that that code corresponded to.
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.
And eventually, the government mandated
that all cars came with a standardized on board diagnostic
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.
Why am I talking about OBDs?
Because an OBD reader 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.
Let's look at that torque curve again.
With old school tuning,
you could change an engine's performance
but you're really only gunning for the best performance
right here.
Big cams, open valves, lots of variables,
lots of gas.
When you're jetting a carburetor,
you're tuning it for this spot.
When you tune the distributor,
you're tuning it for this spot.
And everything else was off.
But 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.
So we can't do too much to this part of the curve
because that's where the engine performs best.
What we can do is fudge some valve timing.
Intake fuel injection.
In ignition to make it look a little bit more like this
in the low end.
Budge a bit more and make a little bit like this
in the high end.
With engine controls, we've widened our peak performance
from about a 15 RPM range to a 400 RPM window.
That's... pretty good.
The spark in the cylinder is kinda 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 got the best mechanical advantage.
As the speed in 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 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'd just keep changing half and half and half
again and again until they found the value
that affected fuel.
Then they'd have to start all over again
to maybe find ignition timing.
Crazy.
Nowadays, all that legwork's been done.
And it's easier to know what to change in your ECU's coding
to change what you want in the engine performance.
I mean, not for me.
I don't know how I could do that.
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.
I'm talking like Beautiful Mind stuff.
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 try,
do it as a hobby.
There's guys who've been doing this since the early days
of ECU.
And they're still learning stuff.
Whoo, that's a lot to talk about.
You wanna take a break, click on the subscribe button.
So how do we know that all the variables were changing?
In fact, what's happening under the hood?
We go back to the OBD.
This is a FIXD OBD II reader.
But the guys that fixed are constantly pushing to see
how intuitive they can make these interfaces.
This transmits live data from your car's ECU
to your phone or tablet.
So when the car's running, it can display and record
a ton of data.
After you apply a new tune with FIXD live data,
you can closely monitor and ...
All of these things are tractable and recordable
and mappable with FIXD.
That helps you make sure your new tune is safe
for your vehicle.
And if you think there's any improvements
that can be made in the app,
you can let the developers know.
They're constantly looking for ways to make it better
for people who use it.
Ann OBD II reader can also cue unit of things that are
hurting your performance outside in the tune.
If one of your sensor's is malfunctioning or clogged,
it's gonna 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 the car.
You need a separate computer for that
and big brains.
But an OBD II with a good interface will let you know
what's going on inside of it from the tune.
But what about those chips?
They're clean, 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 and like a blower
or maybe NOS injection,
there is no way
you're cranking out an extra 50 horsepower from ECU alone.
If you have hardware like intake, an exhaust,
or headers, injectors,
well, the engine's gotta be recalibrated
and that is where tuning comes in.
So a chip with no hardware?
It's bad news.
Hardware with no tune?
You're in trouble, buddy.
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.
Tuning.
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And that's because this episode is brought to you by FIXD.
I also think it's a pretty cool OBD II reader.
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