Launch Control

Before I started autocrossing, I was a drag racer; specifically, I was a bracket racer.

The keys to bracket racing success are consistency, predictability, and deviousness. You need to be able to predict how quickly your car will cover the quarter mile to a high level of precision. You need to be able to consistently cut very quick lights (my drag racing average was .514) and you need to be devious enough to figure out how to throw the other guy off his game. (Otherwise known as "sandbagging" - ask Bob Tunnel what it means)

When I came over to ProSolo and discovered that they were using a drag racing tree as their start lights, I was a very happy camper, because launching the car on a Christmas Tree was a skill I already had in spades. I was astounded, however, to find that the majority of my competitors did not have the same skill level. Despite running off a tree for a dozen events a year, most weren't at the level of a decent local track weekend bracket racer. It wasn't considered important.

Then I introduced launch control on my car - and there's no way to hide it. Launch control as a two-step rev limiter, connected to the clutch pedal. When the clutch pedal is out, the rev limit is the normal rev limit provided by your engine builder. When the clutch pedal is in, the rev limit is set to whatever maximum engine RPM the drive tires can stand at launch.

You pull up to the lights, engage the clutch (activating the lower rev limit) and floor the throttle. The rev limiter keeps the engine RPM at exactly the ideal revs for launching, and the driver concentrates on the lights and the first corner. Launching is no longer an issue; just dump the clutch and go.

Oh, and if you have a turbo car, you build boost at the line. My car would build 10 PSI at the lights.

Datalogger Recording of a Launch Control Start

My particular combination of launch control, AWD, and a spooled-up turbo meant that no car in the sport was faster to the first turn than mine. The car would cut 1.5 second sixty foot times (drag racers - that's on an unprepared surface), go 0-60 in 3.2 seconds, and would have as much as a three car length lead at the end of the first straight. And it was EASY. I never had to worry about launching the car - at most, I might have to tweak the launch RPM up or down 100 RPM to better match the grip available at the start line.

And devious - all that popping and banging on the line was distracting (and to some, intimidating). I know for a fact that I distracted/frightened some competitors into screwing up their own launches.

There was absolutely no downside to this setup and it paid huge dividends. Yet amazingly (even though it was impossible to hide) almost nobody ever copied it. Go figure.

If you compete in ProSolo - and especially if you have a turbocharged car - you need to activate the two-step rev limiter function. If you have an AEM EMS or an MSD DIS ignition box, it is already there, waiting for you to use. It greatly simplifies launches and lets you concentrate on the lights and the first corner.