Horsepower and torque are the product of both air and fuel. The more of both (in the correct ratio) that you can squeeze into your 2005 to 2009 Mustang GT's 4.6L V8 the more power it makes. Our selection of air and fuel upgrades will have your Pony pushing out a ton of extra horsepower and make your Mustang feel like an entirely new car. Because your Mustang runs slightly rich from the factory, you should start off with a cold air intake, throttle body, or tuner package for easy and awesome horsepower gains. In general, you don't really need to update any part of your Mustang's fuel system until you're putting a lot more horsepower over stock, but for those of you throwing down a ton of power or putting together a supercharger or turbocharger tuner kit, then you're going to need some up-gunned fuel hardware.
Where should I start?
If you're starting anywhere besides our cold air intake section, you're probably doing it wrong (unless you're an exhaust or suspension type of person). A Mustang cold air intake (CAI) provides your engine with a larger amount of cooler charge air than your factory air box and giving you up to a 15 horsepower gain with a basic "tuneless" kit. For more power, you can grab one of our intake and tuner packages that will provide even more power.
Do cold air intakes require tuning?
The short answer: yes and no, which is really not all that helpful. The long answer is that some cold air intakes do not require tuning (like the Airaid MXP series, BBK's silver and black intakes, and the Roush cold Air Intake) do not need tuning. Some (like the Steeda ProFlow, Airaid "Race" Series, and JLT Series 3) require PCM tuning in order work properly and avoid engine damage. Despite not "requiring" a tune, our more basic Mustang cold air intakes can still greatly benefit from custom tuning and get more power than just the intake upgrade alone.
Do I need tuning for a throttle body?
In general, it's a good idea to get an aftermarket throttle body tuned. Both Ford Racing's 62mm Throttle Body and Metco's GT500 conversion kit require tuning, while BBK's 62mm Mustang throttle body functions much better with tuning, though it doesn't necessarily require it. If you are using a cold air intake and a throttle body, then tuning will definitely be required.
When do I need to get larger fuel injectors?
For basic bolt-ons, probably never. 2005 to 2009 Mustangs came with 24lb/hr fuel injectors from the factory which actually hold up pretty well for all but the most powerful bolt-on combinations. You can usually pull off a cold air intake, throttle body, underdrive pulleys, shorty headers, catted mid-pipe, and tuning without needing injectors. If you're making the jump up to something more powerful like long tube headers and aggressive aftermarket camshafts, then jumping up to 34lb/hr injectors may be required, depending on how much horsepower you're making. Supercharger, turbocharger, and some nitrous applications will definitely require larger injectors, though most blower and turbo kits have them included.
Do I need tuning for underdrive pulleys?
Nope! Mustang underdrive pulleys don't actually effect your Mustang's air or fuel (why the hell are they in this section?) and don't require PCM tuning. Underdrive pulleys get your Mustang more power and torque mechanically by slowing down the speeds of your belt-driven accessories and don't alter airflow or fueling.
Where should I go from here?
Generally, the big "second upgrade" for the 2005 to 2009 Mustang GTs are axle-back kits or other exhaust systems. Many others bounce over to our exterior parts section to give their Mustang a little bit of a refresh. The rare bird or two heads over to our suspension section to give their Mustang some top-quality handling gear.