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Generally, he set the timer to activate an amount of retard just moments after the launch. This gives an initial full shot of power to the rear tires and suspension. The amount of retard all depends on reading the track and conditions. We heard it can range from 1-10 degrees but is usually all back in by the 60-foot marker.

Laptops are becoming normal tools for racers and Richie Kolb, who tunes Real Street Champ Bruce Lagory's Barracuda does a lot of tuning via his PC. Kolb pulls timing out during the holeshot to soften the blow of their 513ci BES engine.

In the last few years, digital technology has been incorporated into ignition controls, which has opened a new world of tuning aspects to racers. One of the most popular choices seems to be MSD Programmable Digital-7 Ignition Control (PN 7530). This unit is legal in all competition and is on the majority of NHRA Pro Stock cars. This ignition is programmable from a laptop PC and has step retards like their accessories, but one unique feature is a timing curve that can be used exclusively during the holeshot.

There are two timing curves in the ignition software; one is a run curve and the other is a launch curve. The launch curve is only used in first gear, and it is deactivated when there is an rpm drop. This allows racers to plot a timing curve designed to get the car out of the hole. The timing can be retarded in 0.1-degree increments for every 100 rpm from 800-12,000 rpm!

MSD also offers a retard that can be ramped in over time during the launch. In this program you set a retard amount that activates as soon as the transbrake or clutch switch is released. Then you set an amount of time that it takes for the retard to ramp back to normal timing. This is adjusted in 0.1-second increments and is similar to the same affects of using a timer to activate a step retard, except this ramps the timing back in smoothly rather than abruptly turning it off.

Chart courtesy MSD Ignitions

As you can see, there are several ways to tune-in traction. Just like setting up an aggressive clutch setting or taking away some boost pressure, the ignition timing provides yet another window of tuning opportunity. Though the racers we talked with treated their exact retard amounts like their cam specs, they provided us with a new way of thinking about getting traction from a small tire car. It's certainly not the hold it to the floor, dump the clutch, and drive through the tire spin way of thinking any more.

But when you look at some of the e.t.'s that these and other DOT-equipped cars are pulling down, you know that there's a lot more thinking and work going into this kind of heads up racing!

PRO-DATA+ SOFTWARE TUNING

It would be safe to stay that the largest contingent of racers do not welcome technical changes or computer technology until they really absolutely have to. Most go by the "if it ain't broke..." credo. And we know that we fit that mold in many aspects. MSD set out to make its programmable software easy to use and understand. If you can play solitaire on your computer, you can program a timing curve with MSD's Pro-Data+ software.

The launch curve is activate when you supply 12 volts to a reset switch that can be tied in with your trans brake, clutch switch or a two step button. This curve will be active from the moment you release the button until the ignition determines that you've shifted gears by recognizing a substantial drop in rpm (this is also adjustable). Once you shift, the ignition switches over to the "run" timing curve for the duration of the pass. The example shows the timing at the total timing setting until 3,000 rpm. Between this point and 3,100 rpm the timing is retarded 15 degrees and remains retarded through 5,000 rpm. Between 5,000 and 8,000 the timing is ramped back for a smooth transition back to total timing. By this time the car should be hooking and moving! At 8,200 rpm a shift occurs and the ignition changes to the run timing curve.

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