What Is a Tuner And Why Do I Need One?
Most modern cars are ultimately designed for the middle of the road, where one side is acceptable performance and the
other is reliability and fuel efficiency. This even includes the Ford Mustang sports car. Even when we consider the
performance car segment, the vast majority of car buyers seek this bland driving experience. Also consider the fact
that the Corporate Average Fuel Economy (CAFE) regulations hang over the head of the entire auto industry, and the
result is untapped potential stuck inside every car on the market.
When it comes to your Mustang’s performance, you want to unlock the true potential of your pony car, and
perhaps you have already performed some modifications to your intake system, exhaust, or EcoBoost turbo setup.
However, no matter what upgrades you have already performed or are considering performing, engine tuning is
absolutely essential. Getting the best tune for your Mustang will not only extract the maximum performance gains
from your new parts but also help ensure that your engine and its components are operating safely within the new
tolerances that your modifications create.
"you want to unlock the true potential of your pony car..."
An internal combustion engine runs off three main factors: Air, spark, and fuel. Any change in the way the engine
cylinders receive air and fuel will require a modification to the instructions the injectors receive from the engine
computer. Your Mustang’s stock ECU (Engine Control Unit) was programmed with instructions for all of the
various parts of your engine involved in delivering air and fuel to the cylinders. If you change any of these parts,
you must replace the instructions the ECU is sending. This is usually accomplished by providing the ECU with a new
program. Replacing the ECU completely is also an option, though it is a costly one.
Even if you haven’t upgraded any parts on your Mustang, your stock setup can still benefit from a new tune.
Modifying your air-fuel ratio, ignition timing and other parameters can help you change the values in that
performance/fuel efficiency equation, either cranking out a few more HPs or squeaking out a few more MPGs.
What Kind Of Tuner Does My Mustang Require?
Over the years, technology has drastically changed the way these Mustangs operate. Everything from anti-lock
brakes and paddle shifters to side curtain airbags and SYNC voice-activated infotainment. This includes the way in which
a tuner would hook up to your Mustang’s ECU.
SCT Chip for 1989-2004 Mustangs: Beginning in 1989 with the Fox Body Mustang, Ford replaced the old speed
density computer system with a mass air system. This particular change lowered power output a bit but made Mustangs
much easier to modify. Fitting 1989-2004 Mustangs, the SCT Chip is the oldest and most dated way to tune your car,
but this method is tried and true.
SCT X4 for 1996-2019 Mustangs: Starting in 1996, the Mustang was switched over from a pushrod 5.0L V8 engine
over to a modular 4.6L engine. After this change, SCT was able to release a handheld tuner, the SCT X4 for 1996-2014
Mustangs, in which you’ll be able to view and edit some parameters along with datalog your engine’s
output for a tuner to view either on-site or remotely. What is a datalog? Datalogging is essentially recording
various readings off your Mustang’s engine when you’re running it down the dragstrip or street. Tuners
can read this datalog and adjust your tune accordingly, send a revision and have you on your way. Being a very
popular option for Mustang owners, the SCT X4 is also available for 2015-2019 models.
COBB Accessport for 2015-2016 EcoBoost Mustangs: For those with turbocharged engines from the factory, such as
the S550 Mustang EcoBoost, there is a new option on the table for you. That is the COBB Accessport V3. Very similar
to the SCT X4, the Accessport comes from the land of Subarus and other rally-inspired turbo-charged four-cylinder
cars. Just like the X4, the V3 comes with pre-loaded tunes made to work with certain modifications that are also
available from COBB. Since the release of the new 2.3L EcoBoost platform to the S550 Mustang in 2015, COBB has
expanded to the Mustang crowd and has proven to be very successful for COBB Tuning, offering a wide selection of
high-quality Mustang parts for your turbo-fed four-cylinder engine with everything from Cold Air Intakes to Exhaust
Systems, Intercoolers and other power adding mods.
Strategy Tunes vs Custom Tunes
Strategy tunes are known as the “box” or “over the shelf” tunes that initially come with the
tuning device. These tunes are the files that are pre-loaded on your SCT X4 or Cobb Accessport device right out of
the box. They’re very basic and change some parameters in your ECU enabling your Mustang to reap some of the
benefits of your basic bolt-ons such as a cold air intake or axle-back exhaust. Strategy tunes are more than
adequate for a stock or a lightly modified setup. They emphasize the ease of implementation for beginners and simple
modifications at the expense of comprehensive control over your car’s computer systems.
There are couple main differences when it comes to strategy tunes versus custom tunes:
- Strategy Tunes: A strategy tune is great for those Mustang owners who are looking to get the most out of
their basic bolt-ons, but nothing further than that. When you pass the threshold of 'basic bolt-ons', it'll be
time to seek out a custom tune.
- Custom Tunes: In all honesty, you can get a custom tune from the get-go, but most like to use the
strategy or off-the-shelf tunes before seeking out a custom tune due to the additional funds needed for a custom
tune. And then if you were to add additional modifications, most shops will charge for tune revisions. The best
course of action for those who are past the basic bolt-on period is to gather up your additional modifications,
install them and get a tune to support those modifications. Otherwise, numerous custom tune revisions can get
In general, you’d need to have a custom tune created when you outgrow the “box” tune that came on
your tuning device. For example, if you drive a basic bolt-on 2011-2014 Mustang GT and you’re ready to install
a Boss 302 Intake Manifold or add a supercharger to the mix, it may be time to invest in a custom tune so your
Mustang is running and performing at peak efficiency. You would use a computer to create a custom tune and then load
it onto the device, rather than using the tuner to manipulate the variables one at a time. We recommend contacting a
local tuner or performance shop for help creating a custom tune for your specific Mustang build. Once the custom
tune is created by your local shop, you can upload that tune to your Mustang using your handheld device.
Another custom tuning option if you’re in a 2011+ Mustang or 2007-2014 GT500 is to pick up an nGauge tuner from
Lund Racing. Once purchased, Lund Racing will create and cater a completely custom tune for your specific build.
Supporting aftermarket forced induction setups, nitrous, E85 and other modifications, Lund Racing is a great
alternative to an expensive dyno tuner.
Taking Your Mustang In For Routine Maintenance?
Unless you have a heavily-modified Mustang, we suggest using your tuner to return your car to stock before you take
it in to a dealer for service. If their routine service checklist includes updating the PCM, this will likely cause
the tuner to lock out, as it will no longer recognize your Mustang’s tune as the most recent version. If
it’s not possible or is extremely inconvenient to return your car to its stock tune, be sure to communicate
with the service department so they don’t lock you out.
Supporting Mods and Other Important Notes
When you are planning your build-out, consider the effect that each modification has on the entire package. We are
discussing modifications to your car’s engine, but make sure your suspension, transmission and rear end can
handle the increase in power. If you are just implementing a simple out-of-the-box tune, you’ll be fine.
As your hunger for horsepower grows, though, make sure you budget for the other improvements, otherwise known as
supporting mods, which will help hold your car together. An extra hundred horsepower won’t do much good if it
twists your chassis and driveline, or burns up your clutch the first time you unleash it.
- Suspension: Springs, Control Arms, Bushings, etc.
- Tires: For better grip. Remember, spinning isn't winning!
- Driveline: Aluminum or Carbon Fiber Driveshafts, Stiffer half-shafts, etc.
You’ll also want to look at your wheels
and tires. Can they put the extra power down? The factory all-season tires won’t cut it on a
supercharged motor with 600 horsepower. And, if you are taking your Mustang to the track or the drag strip, generic
summer tires may not provide enough grip to control all those extra horses coming out of your car.
CJ’s Gotta Have It Race running NMRA in
The octane of your fuel is another important factor to keep in mind. You’ll notice on some of the more basic
handheld tuners that they have generic tunes for different fuel octanes. Because of the characteristics of gasoline
and its various octane ratings, make sure you are using the correct gas for your tune.
Keep in mind that using 93 octane for a tune that supports 87 octane is technically okay in most situations, however,
using 87 on a tune that’s meant for 93 is a recipe for engine knock and other serious internal issues.
Remember, when custom tuning a vehicle, the higher octane you use, the more power you’ll be able to create.
For example, you could see an increase of 35 hp and 40 ft-lbs of torque on a 93 octane tune, whereas with an 87
octane tune, those numbers could only be 20 and 25 respectively.
While Ford’s EcoBoost engines are designed to handle lower octane gas on the factory tune, the ECU will detune
itself to accommodate the lower octane. Figures for a 2.3L EcoBoost engine using 87 octane have the Mustang’s
turbo reducing power from 310 HP to 275, and torque from 320 lb-ft to 300. Making sure the octane that goes into
your tank matches the tune of your ECU will help keep your engine running smoothly.
The Ever-Popular Question: Will a Tune Void My Warranty?
The most important tool in your toolbox, as is the case with any big project you undertake with your Mustang, is a
healthy knowledge of your limitations and a big bag of common sense. Mustang tuners are designed to modify the
operation of the most delicate and explosive (literally) components of your Mustang and its engine. The potential
for catastrophic damage is real, and it could happen without warning. And while the use of aftermarket parts in and
of itself can’t void your warranty, if you cause damage to your engine by making changes it couldn’t
handle, the trip to your dealer to fix it more than likely won’t be covered by your warranty. Furthermore, if
something were to happen to your engine and you uninstall the tuner from your Mustang, the dealer will still likely
know that there was an aftermarket tune on your car on more recent model year Mustangs.
So how does it all work? Well, in order to initiate a warranty claim, the service provider (usually the
dealer’s service department) must prove that the failure was the result of a manufacturing defect. Dealerships
handle these issues all the time, and the process is generally straightforward.
So what if you have installed aftermarket parts? It all comes down to what caused the failure that has brought your
car into the shop. If it could be argued that these parts caused the failure, the dealer will likely make that case.
If your parts have nothing to do with the issue in question, the dealer isn’t allowed to reject your warranty
claim because you have aftermarket components on your car.
Therefore, the bottom line is that no, your warranty is not automatically voided as soon as you implement one of
these tuning solutions — or any other aftermarket parts, for that matter. If the dealer can make the case that
your modifications, and not a manufacturing defect, were the cause of the issue, though, they can reject the
warranty claim and hand you the full repair bill.
For more information on this topic, the FTC has a great page
explaining their ruling on the subject.
The More You Know
Now that you understand the general idea of the engine tuning world, your next step is to decide the scope of your
Mustang tuning project. Is your tuner the first purchase in a long line of car parts? If your shopping list includes
cold air intakes, intake manifolds, headers, cat back exhaust systems and every other performance upgrade under the
sun, be sure to get a tuner that is capable of programming your engine computer to handle everything safely and
If you are purchasing a tuner to trade a couple of MPGs for a few HPs, that’s okay, too. Whatever your end goal
may be, CJ Pony Parts has an extensive inventory of parts for your Mustang, with an option to improve your entire
car, bumper to bumper. Our friendly, knowledgeable staff will be more than happy to help you get your project
started with the right equipment. Browse our parts section and contact us today for all your pony car modification
Tuners help you to unlock your car’s hidden potential. If you’re just looking to modify your car with a few basic
bolt-ons, then a strategy tune should be enough for you. Custom tunes are more expensive, and many Mustang
enthusiasts like to wait until they’ve finished their build due to the cost of tune revisions that may be necessary
with additional modifications, on the other hand, some modifications, like improving your suspension and tires, will
make sure that your Mustang is ready for the additional power that you'll likely see after a tune.
Though tuner damage won't be covered by your warranty, installing aftermarket parts, including tuners, doesn't void
your warranty. You should use your tuner to return your Mustang to stock before taking it to a dealer for service
though because your tuner could accidentally lock out.
- The SCT X4 is a handheld tuner available for both
1996-2014 Mustangs and 2015-2020
- If you have a turbocharged engine, like an 2015-2020 EcoBoost, then a Cobb Accessport
may be the option for you.
Header Image Credit: OPI Images