Picture this: A two vehicle drag race, but instead of a quarter mile straight line, there are a pair of autocross courses chock full of corners and slaloms. Sounds like fun, right? Well, it IS fun, and the SCCA® has a program where anyone can do it with nothing more than a car and an approved helmet. It’s called ProSolo®, and it’s essentially a mashup of autocross and E.T. bracket drag racing.

If you already compete in SCCA’s Solo® program, then you already know 98% of what’s needed to compete in a Tire Rack SCCA ProSolo Series event. In other words, the point of this article is to fill in as much of the other 2% as possible.

Here are the five things you need to know about ProSolo.

(Ready for launch! ProSolos use standing starts with a drag racing Christmas tree. Being able to stage your car correctly and get a good launch is the key to a good start to your run.)

1. How To Stage

With ProSolo, even in the summer, it’s Christmas time – so instead of a person with a green flag waiting to send you onto the autocross course, at a ProSolo, you stage your car using a drag racing Christmas tree.

The Tree, as it’s commonly referred to, sets up both competing vehicles to be at the exact same starting position on the course using staging lights. The Tree also allows each driver to know ahead of time when competition is about to begin, with three amber lights that “fall.”

Lights falling means the top amber light illuminates, then the second amber light illuminates half a second later, then the third amber light illuminates a half second later. Another half second and the green light turns on and competition begins.

If a driver leaves before the green light illuminates, that’s considered a red light. The red light on the tree (located at the bottom) will illuminate indicating the driver fouled and the run is counted as a DNF (Did Not Finish), which goes down on your permanent record – at least, a permanent record for the event.

(This is the Christmas Tree. From top to bottom: the top lights are for Pre-Stage and Stage. The next three amber lights will fall every half a second before the green light comes on. The red light at the bottom will only come on if a driver has left too early – even if it is just one-thousandth of a second early.)

The first time you pull up to a drag racing Christmas Tree may seem a bit intimidating, but there is really nothing to it. As you pull your car toward the starting line, your front tires will break a beam of light indicating you’re nearing the line – at that moment, the top Pre-Stage light will illuminate. As you inch forward (slowly, easily), you’ll break the second beam of light and you’ll see the Stage light illuminate at the top of the tree. This is where you stop. You want both the Pre-Stage and Stage lights illuminated. Then you wait for the starter to “drop the tree” and look for the amber lights to begin to light up.

2. When To Launch

Once you’re properly staged, the name of the game is to leave as early as possible once the green light is illuminated. The longer you wait to start, the longer it takes you to get through the course and to the finish line.

Experienced drag racers (and ProSoloists) tend to leave on the third yellow – they don’t wait for the green. Here’s why. We already talked about how it takes a half of a second from the last yellow light to illuminate until the green light illuminates. Here are all the things that have to happen between that last yellow light coming on and the green light illuminating:

• First you have to visually see the light illuminate.
• Then you have to tell your brain, “Let’s go!”
• Your brain has to tell your legs to mash the gas pedal and slip the clutch pedal.
• Fuel and air has to enter the intake manifold, go into the combustion chamber, get lit by some spark, the explosion then needs to push the piston to turn the crank, which turns the clutch, the flywheel, driveline, and axles. (For the record, nobody knows how rotaries work.)
• This begins the tires to spin, and those tires need to grab traction on the racing surface and move the car forward enough to break the final beam of light that is in front of the Pre-Stage and Stage beams of light.

Yeah, that’s a lot of things that have to happen – and, it turns out, it takes about half a second for it all to go down. This is why you leave on the third yellow. You’re essentially jumping the gun and hoping your car breaks the last beam of light just as the green light begins to illuminate and not a single thousandth of a second before.

(Launching is easy. Don’t over think it. When the third yellow light comes on, you go!)

3. Reaction Time

Reaction time is the amount of time it took your car to leave after the green light was illuminated. If you did it perfectly, you would assume that would equal 0.000 seconds. And you would be wrong.

ProSolo uses a 5/10ths tree (it takes half a second between each of the lights to illuminate), so a perfect reaction is scored as actually 0.500 light. If you go 0.499, that’s one-thousandths of a second too quick and you will see the red light at the bottom of the tree illuminate as you leave the starting line. This is usually when foul language is heard on the in-car footage.

The goal is to leave as early as possible without red lighting, so drivers are always chasing the “perfect” 0.500 light. If you get a perfect light at the ProSolo, you’ll earn a free entry to a future ProSolo event (nice!). If you play it too conservative in an attempt to avoid a red light penalty, then your run will take longer, and that means you may lose the battle.

For example, if you’re asleep at the line and get a 1.152 reaction time, that means you left 0.652 seconds after you could have (1.152-0.500), which adds 0.652 seconds to your course time. Anyone who competes at National level in SCCA Solo knows 0.652 seconds on a run could be the difference between first place and tenth place, or more.

Reaction time absolutely matters.

For those of you who’ve spent a lot of time at drag strips, you’ll have an advantage at a ProSolo. However, one important thing to know about reaction time in SCCA ProSolo versus E.T. bracket drag racing with the NHRA is that the reaction time with the SCCA is represented in the time on course. If you have a 0.751 light (0.251 reaction time) and you have a time on course of 48.000 seconds, your time in the results will show 48.251 seconds). In NHRA drag racing, the reaction time is not listed as part of the actual quarter mile time. If you sit at the start line for 10 minutes after the green light comes on with the NHRA and then you leave and run a 13.00 second quarter mile, your time slip will still show you had a 13.00 second quarter mile time.

Why this is important to understand is that when you’re looking at your times as you navigate the left course and right course of a ProSolo event, any change in your times on course aren’t just differences in how you navigated a slalom – a slower time could be just a poor reaction time. The good news is the results list your reaction times, so you can subtract that reaction time from your final times to better understand what your car is doing on course.

Yup, you gotta do some math.

(Regardless of who you're up against, landing a fast reaction time is always going to help. Photo by Rupert Berrington)

4. How Competition Works

Now that you know how to stage, how to leave the line, and how reaction time effects overall success, now let’s talk about how ProSolos are run.

Basic autocross rules and classing is used (with a few tweaks). In order for a class to be considered for trophies, there has to be five drivers entered (so bring a friend and make a class). If you don’t have five drivers in your class, you’ll go to a “bump” class where you’ll compete against other classed cars that didn’t have enough to make a class themselves, and your times will use the ProSolo Index (PSI).

PSI in ProSolo is like PAX for regular autocross, but it follows its own index (which can be found in the ProSolo Rules). For example (and as of the time of this writing), at a Solo National Tour, A Street has a PAX of 0.826. In ProSolo, a two-wheel-drive A Street car has a PSI of 0.830 and an all-wheel-drive car has a PSI of 0.832. The reason for this is all-wheel-drive cars launch better so the adjustments in ProSolo are designed to tighten up competition fairly.

There’s a 50-foot burnout area (delineated by large green cones) prior to the start line where you can heat up your tires. You stage, wait for the lights to fall, then attack the course. As soon as you complete one side, you then move to the other side and immediately run again on the opposite course, all the while someone else is doing the same on the opposite course. During a perfect weekend, each driver will get four shots at the courses (two left side runs and two right side runs) Saturday morning, then four more runs Saturday afternoon. Sunday morning brings four more runs. That means you’ll have six total left side course runs and six total right side course runs during class competition. SCCA takes your best left side and your best right side for a total time – the fastest combined time in each class is the class winner for the weekend.

Your left and right side runs don’t have to be consecutive or even on the same day. Any red light starts, though, will be listed as a DNF, and that run will not count (even if it was your fastest – and it probably will be since you left before the light went green).

(If you win your class you’re going to the Super Challenge and you’ll receive this sticker in grid from Vitour Tires.)

5. Qualifying for the Super Challenge

ProSolo events actually have two separate components. First is the class competitions, as explained above – this competition is also qualifying for the Super Challenge and the Ladies Challenge. There’s also the Bonus Challenge (which is a hat draw of names). To explain how the Challenges work, we’ll dive specifically into the Super Challenge.

The winners of each class and other drivers who finish close to the winner’s times (the top 36 drivers) go to the Super Challenge. If you’re in second place in your class but the winner in your class beat you by five seconds, chances are you will not make it to the Super Challenge. If you’re in fifth place but the winner in your class was only half a second ahead of you, you may qualify for the challenge. It’s a sliding scale of percentage of the leader’s time compared to everyone at the event that determines the top 36. In the case of a two-driver car, only the fastest of the two drivers can advance to Knockout Round 3 (K3)

(If you make the top 36, your car goes to impound immediately after Sunday morning runs. The car will remain there until the Super Challenge competition begins. You’re allowed to fuel the car. Pro Tip: bring fuel.)

Three knockout rounds whittle down the top 36 to the top eight. These knockout rounds are run similar to earlier competition. The goal is to run as close to your class winner’s times to move on – if you red light, hit cones, or fall off pace, you’ll probably be eliminated. Once the final eight have been determined, here’s where the E.T. bracket drag racing style of competition begins.

It wouldn’t be fair for an H Street Honda Civic to have to go head-to-head with an A Mod car, so as those two cars line up, the start is staggered. The Honda Civic will leave earlier based on its fast time in previous runs. The A Mod car will have to wait for the difference between the H Street course time and the faster A Mod course time. If they both have perfect reaction times and run exactly their previous course times, they would tie at the finish line. Of course, it’s tough to be consistent down to the thousandths of a second on reaction times and course times, thus the eliminations begin.

Another major difference between ProSolo and drag racing is breaking out. In drag racing, if your dial-in is 13.00 seconds (a time which you arbitrarily choose yourself) and you run a 12.99 second time, you’re disqualified for “breaking out.” In ProSolo, your dial-in is established based on your fastest run during qualifying, and running a quicker time during eliminations does not disqualify you. However, a faster run will change your dial-in for the next round of competition by a quantity of 1.5.

For example, let’s say your fastest left-side time was a 43.56. During the final eight Super Challenge you run a 43.24 left side, improving your time on that side by 0.32 seconds (this is referred to as letting some sand out of the trunk). The SCCA will multiply 0.32 by 1.5, which is 0.48. Then they subtract 0.48 from your fastest new time (43.24 - 0.48 = 42.76). The next round, your dial-in will be 42.76, and you’ll have to do your best to go that fast (which you haven’t done all weekend). If you can’t go that fast, your competitor on the other side has an advantage to eliminate you. Any red lights in the Super Challenge equals elimination. If both driver’s red light in the same round, the one closest to 0.500 gets the win.

(If you podium in your class at a ProSolo, you earn a cool medal. If you win the Super Challenge or Ladies Challenge, there's money to be had!)

Just like in regular class competition during a ProSolo, Challenge competition allows someone to quickly check tire pressures or make shock adjustments prior to entering the burnout box, but you cannot use water to cool tires.

Great reaction times and consistency on course are keys to being successful in ProSolo, and if you’re successful enough to finish high in your class, get through the knockout rounds, and then win the Challenge competition, congratulations! There’s prize money to be had both on the event level and for the season-long battle. For the Super Challenge, there’s the JCJ Cup, which comes with an overall championship purse of $700; the season-long Ladies Challenge winner earns the Fletcher Cup and takes home $450. There’s money for second and third, too!

In total, ProSolo awards $26,500 in prize money annually!

If you haven’t tried it yet, give the Tire Rack SCCA ProSolo Series a chance. Drag racing with corners is REALLY fun. And remember, when that last yellow light comes on, hit the throttle!

(About the author: Rob Krider is a national champion racer, the author of the novel Cadet Blues, and is the host of the Stories and Cocktails podcast.)

Photos by Rob Krider, unless otherwise noted.