Back in the day, electronics referred to transbrakes, delay boxes, and throttle stops. With all due respect to the older crowd, in an era when 3,500-pound door slammers are running 7-second e.t.’s on 275 drag radials, it’s time to reevaluate the meaning of the word. Today’s small-tire drag racers are setting the scoreboards on fire thanks to a one-two tandem punch of staggering horsepower and incredibly efficient power management, and neither would be possible without the rise of modern electronics. If there’s traction to be had on a dragstrip, today’s advanced electronics will find it, and there’s no better way to go faster than to put the power your engine is already making down to the pavement more efficiently.
To help racers accomplish this, MSD revolutionized the small-tire drag racing scene with the introduction of the Programmable Digital 7 ignition box nearly eight years ago. Instead of relying on driveline sensors to directly measure wheelspin, MSD came up with the ingenious concept of limiting engine acceleration. In essence, it provided a means of controlling traction without utilizing a traditional traction control system. Always looking to up the ante, MSD recently unveiled the next generation of programmable ignition systems with the Power Grid. As good as the Digital 7 may be, the Power Grid promises to be even better, so naturally, we wanted to take a closer look at both systems to see what they have to offer.
That said, making lots of power and putting it down to the ground won’t get you very far if you’re blowing up every other pass. Enter data acquisition, which enables racers to monitor every aspect of an engine’s vitals to not only maximize performance, but enhance reliability as well. Since it’s impossible to monitor dozens of engine parameters while driving—such as ignition timing, air/fuel ratio, inlet air temperature, boost pressure, and exhaust gas temperature—data acquisition systems record all that information for you, making it possible to review the vitals on a computer after a run. In addition to engine sensors, data acquisition systems can record a bevy of chassis and driveline parameters as well, such as driveshaft rpm, shock travel, and torque converter slippage. Racepak is the undisputed leader in data acquisition systems, and the company has just unveiled a budget-priced Sportsman system for weekend warriors. To get up to speed on the latest trends in modern electronics, we sought the expertise of Todd Ryden of MSD and Tim Anderson of Racepak. Here’s what they had to say.
The MSD Digital 7 ignition box, PN 7531, has become very popular in small-tire drag racing classes due to its effectiveness in maximizing available traction. In order to optimize traction, there are two main programming options in the 7531 box, the slew rate limit and the rpm limit by time. The slew rate limit is a rate of acceleration rpm limiter that is probably talked about more than used. Racers can set the maximum rate an engine will accelerate—say 1,000 rpm per second—and if the motor tries to exceed that rate due to wheelspin, the Digital 7 will cut spark to keep the engine acceleration rate within the set target. The time-based rev limit, commonly called “racing on the dots”, allows racers to program a rev limit that adjusts by time. Both features can help in reducing e.t.’s, but when programmed improperly, both could slow you down. That’s why proper setup is imperative.