The electrical system in a first-generation Mustang is one of the areas that needs to be upgraded in a high-performance car. The original systems were very basic with little capacity for extra equipment. This isn’t surprising when you consider there was little more than a very simple radio, some lights, a horn, and only some of the bare-bones basics found on modern vehicles. There often were no power locks or windows, no rear defroster, no A/C, no power seats, and certainly no navigation, bluetooth, electronic fuel injection (EFI) or other things that are ubiquitous in newer Mustangs.
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Should you decide to add EFI, a high-powered ignition, electric cooling fans, power windows/locks, an upgraded audio system, and so forth you very quickly become aware of the limitations of the stock system. Fortunately, you have numerous ways to add functionality and improve performance. You must take care of the basics in terms of having good grounds, no short or open circuits, etc. The rest of the electrical system (wiring, connectors, terminals, grommets, and so forth) must be in good shape. There’s no point in putting in better equipment if the rest of the vehicle is not up to par. Do a complete assessment of the electrical system and make repairs as indicated by the factory service manual before you make any modifications. This will surely save you trouble later.
High-Output Alternator
Having a more stable voltage level can be an absolute necessity if you convert to EFI. Even with just a higher-power ignition you can see significant performance improvements due to less misfire and a hotter spark (see Chapter 4). Power locks and windows become a more reasonable possibility with a better alternator. This provides added functionality and convenience with a negligible weight gain plus it can also improve personal security.
Modern alternators not only can offer higher total output but they also can offer substantially higher output at idle speed. This is especially critical when you have high-current modifications such as an electric cooling fan, upgraded headlamps, driving/ fog lamps, air conditioning, and/or a high-output audio system. Modern alternators can have better output and be far more reliable, smaller, and lighter for the same or an even higher output.
One example of a cost-effective way to upgrade your original alternator is this PowerStar model made for Painless Performance by Powermaster. It’s a direct bolt-in for the factory part yet has much higher output, especially at lower RPM where you need it the most if you add things such as an electric cooling fan. The single-wire design of the PowerStar alternator along with its internal voltage regulator may require some minor adaptations. If you use the single-wire feature (the alternator automatically activates above a given RPM), life is simple: just run a suitable wire from the alternator output to the battery. It also allows you to adjust the output voltage and has a V-belt pulley for compatibility (serpentine is also available).
Many are much easier to install and present a cleaner underhood appearance because they have internal voltage regulators and thus can use fewer wires. Some even allow you to manually adjust the output voltage to improve performance under certain conditions.
Special alternators intended primarily for racing use are available to handle sustained and/or extremely high RPM. These may be appropriate and even necessary but they’re not the best choice for a street car in terms of durability and resistance to weather. They tend to not have particularly high output, especially at lower engine RPM. Those intended for endurance races can be an exception but they tend to be pricey. Aftermarket companies (such as Painless Performance, Powermaster Motorsports, and others) have better options available for Mustangs in terms of price, performance, appearance, and so forth.
The PowerStar high-output alternator made by Painless Performance, for example, has very high output (92 amps) at idle and a significantly higher (113 amp) total output. It bolts right in to most firstgeneration Mustang engine compartments and may only require some minor modification of the wiring harness due to its internal regulator and single-wire configuration. It also has significantly upgraded materials and components so it’s well suited for high-performance use yet is still able to handle street use and achieve excellent durability. This model also has the capability to manually adjust the output voltage. Painless has many color choices, other models with significantly higher total outputs (up to 200 amps!), and v-belt or serpentine drive pulleys.
Upgrading the forward lighting is simple, yet tremendously effective. Much higher output headlamps with vastly improved optics/lenses that are direct replacements for the original sealed-beam units are readily available. Units such as these from Hella look very much like the original lamps yet function much, much better. Due to their generally higher current draw, however, such lamps usually require minor modification of the wiring harness. These vehicles also features high-output halogen driving lamps instead of the factory fog lamps. These lamps (also by Hella) provide a very narrow beam over a much longer distance to dramatically improve visibility when driving at higher speeds at night. These also require some minor modification to the wiring but they come with a dedicated harness to simplify the task.
Headlamps
Upgrading your headlamps is a performance enhancement and a safety improvement as a result of the superior visibility it provides. The sealed-beam headlamps that came with first-generation Mustangs were state-of-the-art technology in their day but things have improved significantly since then. Modern vehicles now generally rely on removable halogen or xenon/HID bulb “capsules” that are inserted into fixed reflector assemblies that are an integral part of each new vehicle’s styling. LED technology has just begun to be utilized for daytime running lights and, at the time this book was written, have just begun to be used for headlamp applications.
Fortunately, owners of early Mustangs can benefit from this constant evolution of technology as these newer technologies become less expensive, thus allowing the aftermarket to develop products that retrofit to older cars. The prime example of this is the ability to convert the original sealed-beam headlamps on your Mustang to halogen technology. Several aftermarket and OEM suppliers offer simple, direct-replacement products that allow you to remove older lamps and replace them with betterperforming lamps.
In most cases, the new lamps even utilize the same type of electrical connectors as the original lamps so there’s no need to modify the wiring. However, in cases where the current draw of the new lamps is significantly higher than that of the original lamps it is advisable to modify the factory wiring to incorporate relays to provide better performance and less chance of problems. Several manufacturers offer special harness kits specifically for this.
These Hella replacement headlamps install directly in place of the original sealed beam units with no modification other than possibly the installation of relays in the wiring harness if their wattage rating is substantially higher than stock. These lamps provide much more light, which is also of a more natural, whiter color than stock so visibility is further improved. The lens also features a European-style, sharper cutoff to the lighting pattern, which helps to avoid glare for approaching drivers. These lamps use replaceable H4 bulb capsules, which allow you to only replace the bulb.
When installing upgraded higher-output lighting in an older vehicle it is often necessary to upgrade the wiring harness as well because the stock harness can’t safely provide enough current for the new, higher-wattage lamps. Fortunately, several companies (such as Painless Performance Products, Mustang Project, and others) offer ready-made kits specifically for this purpose. These usually include relays and a special harness that plugs right into the original factory harness and connects directly to the new lamps (which have the same terminals as the factory lamps). You then run wires directly to the battery and to a good ground. This basically turns the factory wiring circuit into a switching-only circuit because the current for the lamps is now provided directly from the battery over new circuits with upgraded wiring. Even if you don’t upgrade your headlamps, installing a relay system like this can greatly improve the performance of your original sealed beams because it ensures greater current and higher voltage at the lamps while also minimizing the effects of corroded terminals, small-diameter wires, etc., that may increase circuit resistance. (Photo Courtesy Painless Performance Products)
Halogen lights coupled with improved lens and reflector technology provide greatly improved visibility versus the original sealed-beam headlamps as well as a cooler, bluer light. The latter helps drivers see roadside features such as signs more easily while also giving the older vehicle a “newer” look. The ability to simply remove and replace the bulb capsule is a further advantage versus having to replace the entire lamp assembly as with a sealed-beam unit.
It’s unlikely there will ever be many products for early Mustangs that use xenon/HID technology. This is due primarily to their high cost and the need to have specially shaped reflector assemblies that do not lend themselves to being aesthetically integrated into the styling of older vehicles. This is of little concern, however, because there are already LED-based solutions available for these cars, which provide an even lower current draw than the xenon/HID lamps (which is less than halogens) without the need for the expensive electronics required by xenon/HID lamps.
These LED headlamps are simple direct-replacement parts just like halogen units yet they draw significantly less current, last even longer (almost indefinitely), provide an even whiter (more natural color) light, and are very cost effective once you consider they can use the factory wiring without the need for relays, etc. Although they may not yet have as much maximum light output as the xenon/HID lamp this will surely change with time. They are, after all, available now at a significantly lower cost.
LED lights provide far greater illumination than typical halogens. These lamps are a direct replacement (notice the wiring pigtail and connector with matching terminals), although they are relatively pricey. That should change over time, however, as LED headlamps become more common. Still, these lamps last about 50 times longer and also draw much less current (4.5-amp high beam, 2.5-amp low beam) compared to conventional lamps. These lamps are DOT approved so they are fully street legal in the United States. (Photo Courtesy Mustang Project)
Here is an example of LED lighting modules applied to the instrument panel. The light can be considerably brighter than incandescent bulbs provide while still capable of being dimmed as desired. LED modules should never have to be replaced once they’re installed plus they also use less electricity even at much brighter settings.
They outperform and last longer than halogens plus they are easier to install than the HIDs; they install just like the original lamps. LED headlamps do, however, have a higher initial cost and a unique appearance, which may not appeal to everyone.
Other LED Upgrades
You can improve safety and visibility even if you decide not to upgrade your alternator through the use of LED technology to replace some of your regular light bulbs.
LED lighting technology offers many advantages, including brighter/ whiter light, longer life, lower current draw, better visibility, and unique styling, when compared to regular incandescent lights. In most cases the upgrade to LEDs involve little more than removing the original bulb and replacing it with the appropriate LED module. Some applications require the replacement and/or installation of other components (such as the flasher) but there is no need to install relays or modify the wiring because of their lower current draw. Once the LEDs illuminate there’s little doubt something’s been changed due to the unique light signature, greatly increased brightness, different temperature, and even color, if desired. The instrument panel is a prime example of where the almost-infinite life of LEDs is a particular asset because replacing those bulbs is not generally an easy job.
Rear backup lamps, front turn signals, and parking lamps are among the popular upgrades. In addition, the license plate light, side-marker lights, and even hood-mounted turn signal lights can be upgraded.
The single most popular LED upgrade is the taillamps. LED technology provides improved brightness, visibility, longer life, added functionality (such as sequential strobing), and/or a different-color light for a unique look. Furthermore, little attention is given to the very real safety benefit LED taillamps provide due to the quicker response time. Because LEDs are brighter and look different, plus they also light up quicker and have the ability to flash sequentially, they tend to get the attention of a following driver sooner and more completely, thus providing more time to slow down or stop.
The rear backup lamps on these cars are, to say the least, not very effective in illuminating what’s behind the car. Higher-output LED modules provide much more light output while using less electricity. They’re less affected by deterioration in the wiring plus they last indefinitely. They cost more but they’re a one-time purchase and they provide a unique appearance to go along with their greatly improved performance. Various kits, such as this one made by Mustang Project, include LED lamp modules, new gaskets, and the necessary longer screws needed for proper installation. The LED module is wired into a base that plugs right into the factory bulb socket for very easy installation. An even simpler way to upgrade your backup lamps is to just install LED replacement “bulb” modules rather than these modules. They won’t have quite as much light output or the high-tech look but they are less expensive. (Photo Courtesy Mustang Project)
Custom LED strips can be used for a CHMSL (center high mounted stop lamp, or “third brake light”) in an older vehicle. This gives your car a more modern/custom appearance plus it can improve safety by making your brake lights more visible (especially in close traffic) and by lighting faster than regular bulbs (giving the driver behind you more time to brake).
This vehicle clearly shows the benefit of adding LED technology to your older car. The LED taillamps are much more visible than would be the case with the stock bulbs plus the added LED CHMSL further enhances safety and visibility while also providing a unique styling element. Because the LEDs last almost indefinitely there is no issue installing them in a location that can’t be easily serviced in the future.
If you want to make an even more bold statement at the back of your Mustang there is the option of upgrading to LED taillamps. These LEDs provide all of the normal functions (brake lights, taillights, and turn signals) plus they produce a strobe effect where the individual lamp segments light sequentially when the turn signals are operated. This kit from Mustang Project is about five times brighter than stock bulbs.
Written by Frank Bohanan and Posted with Permission of CarTechBooks
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