Holley's Annihilator ignition line is a stand-alone digital CD system that has made great
There was a time when all your car needed to run was a spark. Of course, other things like gas and air were also required, but igniting the combustible mix required only a simple spark. With the advent of sophisticated fuel injection and computer-controlled ignition systems, igniting that combustible mix has become more efficient than ever. Along with an increase in efficiency came an increase in power, and today there are four-cylinder engines making as much power as V-8s did 25 years ago.
The aftermarket has embraced this ever-advancing technology, and many companies have sought out highly skilled electronics engineers to add to their payroll. Those engineers have brought bold ideas to the performance world and have offered new ways of making and controlling horsepower with a whole new arena of electronic performance accessories. These electronic devices can do a myriad of things for you and your car, but sometimes require more than just a basic understanding of what's positive and negative in a 12-volt electrical system.
The More Sparks, The BetterIt can all probably be traced back to the first engineer who figured out that since an engine converts the explosive force of combustion into energy (torque) which moves the car, then improving the spark which creates combustion should translate into more power and a faster car. Since an engine's distributor triggers one spark at a time, those same engineers had to figure out a way to either lengthen that spark's duration or strike multiple sparks at a time. The CD, or Capacitive Discharge, ignition system answered all that.
We haven't forgotten about the old analog ignitions, and this race system incorporates som
Analog ControlAnalog ignitions have been around for a long time, and they're still a reliable and inexpensive way to control your ignition functions. Even with digital controllers, the input circuits (i.e. magnetic pickup signal) going into the digital box and the firing (spark generation) of the ignition are still analog circuits. But analog is a slower technology. The typical analog control box, like a two-step rev limiter, may have a 3 percent response time to engine rpm, meaning that at 1,000 rpm the crank will make 30 revolutions before the limiter reacts.
A digital controller reacts within 1 percent of engine rpm, which is almost instantaneous. And the digital controller is inherently more accurate and repeatable, and it's easier to make adjustments with as well. The difference between digital and analog controls can be likened to trading in your B&W TV and old Hi-Fi for a digital satellite Direct TV with five-channel DTS surround sound and DVD capabilities.
Digital ControlThe biggest advantages of digital ignitions are the speed at which information can be processed and their ability to pack more features into a confined space. What used to take multiple boxes and plug-in modules can now be controlled from a few small dials or buttons on a keypad. Also, most digital systems offer computer software enabling you to tune your ignition functions from a PC. Functions like the ignition advance curve, rev limiters, retard steps, individual cylinder spark timing, and even timer-based automatic activation of accessories such as a nitrous system can all be programmed into the digital controller.
With a digital box running the system, advance is controlled by the microprocessor instead of clunky weights and springs. That's very accurate and consistent, and digital processors won't wear out in your lifetime. You can also include a manifold pressure (MAP) sensor to trigger a boost-retard or vacuum-advance signal from a digital box. What some digital controllers do not replace is the multiple-spark CD box like an MSD 6AL or Crane Hi6. Those boxes are still needed for firing the ignition with certain digital systems. The good news about that is that you can now have digital control without shelling out extra cash for a new 6AL box and trashing your old one.
Just wire the new digital controller into your system and sell all those little plug-in boxes and chips to your friends. That is, unless you get a new, all-in-one, complete digital ignition box like the MSD Digital 6-Plus shown, which doesn't require anything but a distributor and coil. Just think of digital control systems as an autonomous passenger that can turn things on and off for you and can retard or advance the timing from inside the car without ever asking "are we there yet?"
The Jacobs Electronics Nitrous Mastermind (left) increases the rate of nitrous flow propor
If you don't run an alternator, you'll be robbing horsepower from yourself. By maintaining
Volts matter and the Auto Meter Battery Tender (top, right) keeps the powerful, yet lightw
Frank's Auto Electric offers this adjustable, electronic, speed-sensitive starter relay th
Progressive NitrousNitrous fixes everything. But too much nitrous can make other parts need fixing. At the very least, introducing too much nitrous to your engine at once can cause tons of tire spin. And since the idea of having nitrous is usually to get to your final destination quicker, then you can see why tire spin is something you want to avoid. By incorporating a progressive controller into your system you can still introduce tons of nitrous into your engine, but over a specific time period. Let's say you want to squeeze 250 hp and you run a small DOT radial tire.
Your car spins the tires well past the 60-mark and your e.t.s suffer accordingly. By programming your progressive controller to start with only 50 percent of the nitrous flow and slowly bring it up to 100 percent over a period of perhaps 1.5 seconds, your traction is regained and speeds improve. Of course, there are other functions progressive nitrous controllers can do, like activate a second nitrous system and shut off the nitrous flow in case of low fuel pressure, but the main benefit comes from their ability to tune themost horsepower-per-traction that your car can handle.
There are several different ways of controlling the amount of nitrous introduced into your engine and the speed at which it flows. The most popular for carbureted cars is a time-based controller. With this type of progressive unit you preselect the amount of nitrous (from 0-100 percent) that starts flowing as soon as you hit the button and you program the amount of time (0-10 seconds) it takes to reach maximum flow. Maximum power with a progressively controlled nitrous system is still adjusted with good old-fashioned replaceable jets.
If you don't want to tune your ignition from a laptop, you can simply plug in this hand-he
It's A Matter Of VoltsFor obvious reasons all automobile electrical systems rely on either the battery or alternator for power. If you drive on the street, you know that your ride won't go very far without a working alternator. And forget about making any real power with low voltage. Although just about any ignition system will spark with less than 12 volts, it takes way more power than that to generate a spark under the heavy pressures of combustion. Basically, you won't win by not running an alternator. Even if you charge your battery after every round, you're still probably not getting enough voltage at the top of the track.
This is especially true if you're running any electrical accessories like a fan, water pump, fuel pump, nitrous system, bottle heater, or even headlights. Just the fan, water pump, and nitrous-bottle heater alone will pull about 40 amps with your engine shut off. If you're not charging your battery with more than 40 amps at the same time, you're in a deficit, and soon enough your car won't even be able to start. That's why you'll see so many of the really big industrial-amp-sized chargers in the pro pits at a big race. The pros know that a small, garage-type charger won't keep up.
To make the best power you'll also need a powerful alternator. These two examples from Performance Distributors (left) and Powermaster (right) are both capable of putting out more than 100 amps. That may sound like a lot, but if your car has A/C, EFI, and a thumpin' stereo, it may need that much just to run.
This photo shows one screen from MSD's digital ignition software which can be tuned with a
Don't fear electrical systems. Instead, embrace the technological improvements they can offer and go digital as soon as you get the chance. Your engine will thank you after it's been digitally wired for speed.
Ultimate ControlFor those of you who are serious about tuning and performance, the Crane DEC9500 is the hot ticket. Capable of controlling all high-end ignition CD boxes like the Crane HI-6, HI-7, and HI-8, as well as the MSD 7AL2, the DEC9500 can also be used as a stand-alone dyno ignition controller. With its multitude of functions and ease of programming change with the joystick on its cover, the DEC9500 offers outstanding digital ignition control and vehicle performance in one clean, easy-to-use package.
* Three selectable RPM limits with a max limiter alWays active* Three adjustable timing-retard stages and adjustable initial timing* Three RPM switch outputs* Two independent timers* Programmable advance curve* Individual cylinder timing (ICT)* Automatic start-retard adjustable from 0-15 degrees
Holley Performance Products
1801 Russellville Rd.
Bowling Green, KY 42101
Autotronic Controls Corp. (MSD)
ACCEL Performance Products
10601 Memphis Ave. #12
Frank's Auto Electric
151 Garfield Ave.
Auto Meter Products
413 W. Elm St.
530 Fentress Blvd.