Best Power Adder for My S550

There are three types of power adders available to add some serious performance to your S550 Mustang. These power adders are a nitrous kit, a turbo, or a supercharger. Also don’t be surprised if you see a nitrous kit used on top of either a turbo or supercharger; those guys really have a need for speed.

It’s important to note that when adding any type of power adder it is absolutely necessary to make sure you have an adequate fuel system to keep up with the demands. You'll also need a custom tune to ensure everything is functioning as effective and efficient as possible. I will break each power adder into three main sections:

• What parts the kit consists of
• How the power adder operates
• The pros and cons of adding each system

Historically speaking, superchargers and V8 engines go hand in hand. With the arrival of the 2015 Mustang, it's no different. Rousch, Whipple, Procharger (all major supercharging companies) have already released a blower kit for the 2015 Mustang. Blowers are known for their relatively painless installation process (in regards to installing power adders), and with a proper tune, easily push another 200 horsepower out of the already mighty Coyote engine. There are two types of superchargers, positive displacement and centrifugal type.

• Positive displacement: A positive displacement charger bolts directly on top of the engine, in place of the intake manifold. Driven off the crankshaft by a belt, a positive displacement charger is able to provide peak boost at low RPM – great for launching hard off the line
• Centrifugal type: A centrifugal supercharger is essentially a turbocharger, however it is driven mechanically by a belt as opposed to exhaust gases. The centripetal force of the vanes spinning inside the housing draws air in and outputs it as high pressure, low velocity. The faster the engine is spinning, the greater the pressure (more boost) becomes, equating to more power. Centrifugal type chargers make peak boost at higher RPM

Ranging from $5000-$8000, a supercharger offers great power at all RPM levels. And again, it is the classic Muscle car power adder!

These two type of superchargers are very similar. They both house two rotors that are belt driven, and they both sit directly on top of the motor. They have their own self oiling system which requires some maintenance from time to time, and they use a heat exchanger that is part of the intake manifold.

The power delivery from positive displacement blower is almost instantaneous. The supercharger is sitting directly on top of the engine, so the air has to travel the shortest amount of distance when compared to other power adders.

There are only a few differences between roots and twin-screw setups. Roots style blowers are the ones Ford traditionally puts on their power hungry Mustangs because of how consistent and reliable they are. Twin-screws work in the same fashion, but the shape of the rotors is slightly different, and they have much tighter tolerances.

This allows the supercharger to handle high boost applications, but in turn generates more heat since the internals are closer together. Twin-screws can handle more boost (psi) than a roots style blower. Positive displacement blowers often utilize a bypass valve which bleeds off some air from the supercharger at really low RPMS. This helps make the system more efficient and allows the boost to come in a bit smoother.

Centrifugal superchargers are rather unique. They are secured by a mounting bracket which bolts the supercharger somewhere in front of the engine, and it's either belt or gear driven by the engine's crankshaft.

A big benefit of running a centrifugal setup over a positive displacement (roots/twin screw) supercharger is since this isn’t mounted directly on top of the engine, heat is not nearly as much of an issue. This system can also utilize an air-to-air intercooler to keep the temperature of the charged air even lower.

Centrifugal blowers work similarly to a turbocharger in the way they compress air because they bring in ambient air through an impeller wheel, but instead of being driven by exhaust gas the impeller is belt or gear driven.

Centrifugal supercharger setups deliver power similar to a top-mount supercharger. It will give you good mid-range and top end power, but the curve is more linear than a turbocharger. A turbocharger usually has a very quick peak in the mid-range and continues to stay at a high power level, but a supercharger gradually works its way up to the same area, making the supercharger more predictable and usually more reliable.

Turbochargers have gained massive popularity of late. The days of using turbo chargers only on imports or very high performance engines are long gone. Turbochargers operate on the same principle as the centrifugal supercharger in the paragraph above, except for one difference.

Turbochargers are energized by the exhaust gasses of the engine, whereas the supercharger is driven by the engine itself. Due to this, turbochargers are highly efficient. They pose little restriction to energize, and provide massive gains in power. Imagine this: a 1000 HP twin-turbo 5.0L Coyote monster Mustang! You don’t actually need to imagine this – such Mustangs exist.

Turbochargers have that “new school cool” feeling to them, and if sized properly, do not pose any great lag that was often talked about in previous decades. On the other hand, turbo systems are more complicated to install, as they require special headers and a lot of extra piping.

Getting a turbo system to fit in the engine bay can sometimes be a challenge. Price wise, they are nearly comparable to a supercharger system – usually a tad more expensive.

A wastegate’s main purpose is to regulate incoming boost. Once the desired amount of boost is obtained, the valve inside of the wastegate will open up to bleed off any additional pressure. A blow-off valve helps relieve the pressure on the intake side. A car builds boost as more throttle is applied, and when you let off the throttle the remaining air must be released.

The major variable in turbo kits is the size of the turbocharger itself. Picking the right size turbo for your application is crucial in making significant power gains. Generally, the bigger the turbocharger, the more power it's able to produce.

The smaller the turbocharger, the quicker you can spool the turbo and achieve boost. Turbos work off of exhaust gases. The gas spins the turbocharger to pull in an exponential amount of fresh air, giving you some serious horsepower and torque.

It's usually pretty easy to set the boost level with a turbo kit as opposed to a supercharger. These systems are first regulated by a wastegate spring (6psi, 10psi, 15psi, etc.) and can then be modified by using a boost controller.

A boost controller  tricks the wastegate into thinking it hasn’t reached full boost yet, so in turn it stays open to create even more boost. For example, you can use a 10psi spring in the wastegate and set your boost controller to add an additional 5psi, leaving you with a total of 15 pounds of tire smoking boost.

The last power adder to examine is a nitrous oxide kit. A nitrous kit, by far, is the cheapest to install and provides gaggles of fun. However, nitrous oxide is only fun for as long as the bottle lasts, and it isn’t always on tap like a super or turbocharger. Nitrous oxide has to be activated specifically, and can only be done at specific times (wide open throttle) to prevent any engine damage. Furthermore, nitrous oxide systems are often NOT legal for street use, making them restricted to track use only. For this reason, nitrous oxide is best reserved for weekend warrior type cars and not daily drivers.

A nozzle kit uses a single nozzle installed somewhere into the intake before the throttle body whereas a plate system bolts directly between the intake manifold and plenum. With higher shots of nitrous, plate systems typically distribute nitrous and fuel more efficiently than a nozzle kit since it’s more of a direct shot a.k.a. less distance to travel. Both kits work great and neither should be discredited.

A dry shot of nitrous will inject nitrous only into the manifold. In this case, the car's ECU is responsible for adding the necessary fuel for the shot of nitrous. A dry kit is the most simplistic in terms of design and installation. A wet shot is a bit safer since this system injects nitrous along with the necessary fuel, but the installation is more complicated.

With both of these kits it's important you make the necessary modifications to your fuel system so it's able to keep up with the added shot of nitrous. By beefing up the fuel system, you will avoid the lean spike that is possible.

To an extent, yes. A wet system is regarded as safer because the nitrous and fuel are premixed. As a result, the nitrous cannot be injected without the fuel. However, on a dry system, if a fuel pump/injector fails, the nitrous is still being sprayed into the engine. Thus, the computer analyzes that more air is required and can lean the engine (or cylinder) out. Dry systems are perfectly acceptable on naturally aspirated, return style systems. However, wet is the preferred method for all applications. 

No, they are not. One big component of a nitrous system is the type of system. The entry level system is regarded as a nozzle system which delivers the nitrous via a nozzle. For smaller shots, a nozzle system is fantastic. A plate system utilizes a different delivery system that is more accurate in nitrous delivery than the nozzle counterparts. Therefore, on larger shots, a plate system is suggested for tuning and safety purposes.

This can be a little tricky, as it depends on the daily driver. If a DD is also used as a track car, it can be a fantastic way of switching between performance pulls and regular driving pulls. However, most states prohibit nitrous to be hooked up when driven on the street (some states have stricter requirements as well). Provided the driver of the car has no issue with disconnecting the nitrous during the work week (it’s as simple as removing the bottle), it’s perfect for daily drivers. 

Yes and no. While the initial setup is significantly cheaper than its super/turbocharging counterparts, nitrous bottles need to be refilled. Every refill can increase the actual cost of a nitrous system. How often a bottle is to be filled will vary based on how often the nitrous is used. The big benefit compared to other power adders is the instant torque gain that it has. Even in comparison to a TVS supercharger, the torque gain is larger in relation to nitrous. 

Like everything in the automotive industry, there are items that can nickel and dime a nitrous setup. Things such as a window switch, bottle heater, purge system, new fuel pump/injectors (to meet fuel demand), aftermarket tune, etc. all play a factor in a safe, effective nitrous setup. While those items are suggested at a minimum, there are many other items that can be factored into the setup as well (remote bottle opener, WOT switch, etc.). 

For 2015 and newer models, there are some differences with nitrous than other years. While an aftermarket tune is basically a must for anything over a 125 shot, a tune is still highly recommended for any amount of spray. Not only does a tune allow for the most performance, it also retains the level of reliability desired. The S550 5.0 coyote engine is very responsive to nitrous when properly installed/tuned. 

Is there one power adder to rule them all? Not really. However, in my opinion, there are two that are clearly on top; and that is the turbocharger or supercharger.

Whether you pick a turbocharger or supercharger is totally left to your preferences, but both provide on-command limitless power that is absolutely second to none for a street machine. Nitrous provides cheap giggles, but due to street legality issues, isn’t really practical if you want to daily drive your 2015 ‘Stang.

If you are able to write the cheque for a nice supercharger or turbocharger system, that is the way to go every time, all the time, hands down.