East Tennessee Region Sports Car Club of America
Frequently Asked Questions

  1. What kind of helmet do I need for autocross?

  2. Where can I buy a helmet?

  3. What time should I arrive at the event site?

  4. I’ve never done this before. How will I figure out what I’m supposed to do?

  5. What is PAX/RTP?

  6. I need numbers on the side of my car?

  7. Where can I purchase magnetic numbers?

  8. How do I join the SCCA?

  9. What is tech? (technical inspection)

  10. What class is my car in?

  11. What am I doing?


 What kind of helmet do I need for autocross?

 The ETR has loaner helmets that are available to new competitors. You will have to pick up the helmet just before each of your runs and return it immediately after each run, as we don’t have enough for everyone to keep one during the event.

  You will probably want to buy your own helmet if you run many events. A helmet that meets the SCCA’s rules can be purchased for $50 to $100 dollars.

The current SCCA rules require the helmets to have a Snell rating 2000, 1995, or 1990. Snell usually releases standards every five years and the SCCA requires the current standard or the two previous, so in 2005 the 1990 helmets will no longer be usable (you will need a 2005, 2000, or 1995). Snell also has sub-ratings. The SCCA accepts M (motorcycle) and SA (Special Application). This may sound a bit confusing, so I’ve included a list of the currently accepted combinations below:

Snell 2000 (SA or M)
Snell 1995 (SA or M)
Snell 1990 (SA or M)

Please note that helmets that only have a DOT (Department of Transportation) rating are not legal in Solo II. Some helmets have both a DOT and a Snell rating, and they would be acceptable providing that the Snell rating meets the criteria outlined above. Also, the M helmets are usually much cheaper than the SA helmets. The SA helmets are required for road racing because they are rated for multiple impacts and have fire resistant linings. If you think you may want to do some road racing you may want to consider spending the extra money for a SA helmet (M’s aren’t legal for road courses). Also, the newer helmets weigh less than the older ones, so the latest rating will probably be easier on your neck. Most of the on-line vendors have a sizing chart so that you can measure your head and get the correct helmet. Local vendors will usually be more expensive, but you can try the helmet on before buying.


Where can I buy a helmet?

 Good on-line vendors are:


Good local vendors:

Gear Up Motosports Inc 865-688-7070
Honda/Suzuki of Alcoa 865-970-2710
Yamaha of Knoxville 865-688-8484
Alcoa Goodtimes Kawasaki Yamaha 865-981-4444


What time should I arrive at the event site?

Read the information that is below the schedule on our Solo II schedule page:


It lists the general times that things happen, depending on which site we are using.

A few notes… you absolutely have to get to the site in time to get your car through tech inspection and to get yourself through registration. Neither of these things takes very long, but if you show up 5 minutes before registration closes, you are too late. If you do not arrive before registration closes, you will not be able to run.

We recommend that you get there in time to walk the course at least three times, in addition to going through tech and registration. You need to become familiar with where the course goes before you try to drive it at speed. We recommend that you arrive around 9:00 am.


I’ve never done this before. How will I figure out what I’m supposed to do?

At the driver’s meeting, we will point out the person who is in charge of helping Novice drivers. Find that person immediately after the meeting. They will answer any questions you have as well as walking through the course with you once. It will help if you’ve already walked the course a few times by yourself. If you have trouble figuring out where the start/end is, or where the course goes, just ask someone nearby for help.

There is also a Novice Class. If you are new to autocross, you can enter your car in the Novice Class. That way your times will only be compared with other new drivers, using a factor (called RTP) to equalize the times. See the section on PAX/RTP for more explanation.

What is PAX/RTP?

RTP stands for Racers Theoretical Performance. There used to be an index called PAX, which is no longer used, but people often still use the terms PAX and RTP interchangeably.

RTP is a multiplier that is intended to take the car’s performance out of the equation and rate just the driver. It basically gives you the theoretical time you would have gotten if you had been driving a car in the fastest class, A-Mod. This way you can directly compare times between two different classes. It also allows classes such as Pro and Novice to exist… giving equalized times between drivers of cars with radically different performance potential.

Here is how it works. Let say you have a car that runs in the B-Stock class. Your best time for the last event was 32.301 seconds. B-Stock’s RTP factor is: 0.826. So you multiply 0.826 by 32.301 and you get 26.681. That is the theoretical time you would have run if you had been driving an A-Mod car. So, say someone in E-Modified (EM) ran a 31.256. E-Mod’s RTP is 0.894 which gives an indexed time of 27.943. So, even though they ran a faster raw time than you, you would have theoretically been faster had you both been driving the same car.

RTP factors change every year and are based in the previous years results at Solo II National Events, Divisionals, Pro-Solos, and other events. The current RTP indexes can be found at:



I need numbers on the side of my car?

The people running timing and scoring have to be able to identify your car quickly. This is why the class and number must be listed on your car. If you are a novice, we will provide free numbers and letters made from paper, which can be taped to your car.

However, once you have run an event or two, you will be expected to have your own magnetic numbers.

The SCCA’s rules for the class/numbers are:

All cars must have car numbers and class letters on both sides. Car numbers will be a minimum of eight inches high and a minimum of 1-1/4 inch stroke. Class letters should be smaller. Both must be of a uniform color and in contrast to the color of the car. All letters and numbers must be on body panels, not on windows, and only one set of numbers may be visible while the car is running. For cars entered in a Ladies’ Class the letter “L” shall follow the class letters (Example: ASL).

I’ll add a few clarifications. The class letters should be about half the size of the numbers, give or take a little. The part about only one set of numbers may be visible while the car is running means that if you are running a two driver car, you must switch numbers between runs. Otherwise it is hard for timing/scoring to figure out who is driving the cars. Additionally, novice drivers need to have an “N” before their class and Pro drivers need a “P”.

The whole point behind the numbers is so that timing/scoring can quickly identify your car while it is on course and give you the correct time when you finish. We will not nitpick the rules on this as long as we can easily read your class and car number while your car is running on the course. When we can’t identify a car, it slows the whole event down because we have to stop cars from running while we figure it out. It is also to your advantage to have correct identification on your car, as it greatly reduces the chance that your times will be recorded incorrectly.


Where can I purchase magnetic numbers?

There are several ways of obtaining them.

On-Line at:


Locally at:

Signs Etc., 10420 Kingston Pike, 865-531-7977

Louie Garza at
Great American Sign & Screen Printing 
Kingston Pike across from Mazda Knoxville

If you are in the Bristol TN/VA area try:

Jerry at
Vinyl Graphic Shop
4885 hwy 11 E Bluff City, Tn 37618
423-956-2878 or 423-895-1841

Or you can purchase the magnetic material and make them yourself. The material can be bought at several local shops like:

Michael's Arts and Crafts
9622 Kingston Pike
Knoxville, TN 37922
(865) 670-9096


How do I join the SCCA?

When you join the SCCA, you need to select a particular region to join. Our region is the East Tennessee Region (ETR), region number 68. National dues are $55 + regional dues ($15) for a total of $70 per year. There are options to add your spouse or family for a few dollars more.

You can join at the event, just ask someone at registration for a membership form.

We recommend joining through the National SCCA. Your membership will be processed a little faster if you send it directly to them. You can get the membership form and additional information at:



What is tech? (technical inspection)

Before any car can run, it must be inspected to make sure it is safe. The basics of the inspection include:


What class is my car in?

 The following web site has a great breakdown on the car classes:



What am I doing?

 First of all, read the Solo II Novice Handbook at:


A quick breakdown of what you should do is:

The night before, make sure your car meets the technical inspection criteria listed earlier in this document.

Arrive at the event around 9:00am or 9:30am.

Registration will be underneath the small tent, next to the Solo II trailer. Check the schedule for the registration opening time. Get in line. The fee for non-members is $20 and $15 for members. Checks should be made out to ETRSCCA. You will need a valid driver’s license and you will be asked for your class and car number. If you don’t know your class, someone will help you. Also, they will assign a car number to you. If you wish to run Novice class, be sure you tell the registration person. They can also give you paper numbers to put on your car.

Tech will open and begin inspecting cars (check the schedule page). Look for a line of cars with the hoods open. Get in line.

Once you get through tech inspection, go walk the course. Anyone will be happy to show you where the course starts and ends, and where it goes. If in doubt, ask or follow a crowd that looks like they know where they’re going. Walk the course until you feel comfortable that you know where it goes.

You will hear an announcement over the loud speaker for the Driver’s Meeting. You must attend this. Please be there on time (the announcer will give a 5 minute warning). We discuss safety issues and tell the driver’s what part of the day their class will be running. Pay attention to the work assignments. You are required to “work” the course once for each heat you drive in. Basically, you will be helping watch for “downed” cones, picking them up, and reporting them to timing/scoring. Don’t worry; you will be paired with an experienced autocrosser. Please note, it is important that you know when you are supposed to work and that you get there on time. This makes the event run better and we will all get more runs.

At the end of the day, it is appreciated if you can hang around and help clean up (stack cones, collect trash, etc.). Afterwards, we award trophies to the top finishers in each class. After that, a bunch of us often go out and get dinner somewhere.

If you have any questions, please join our message board and ask! You can find the forum at:


Finally, don’t be dismayed at all of the details in this FAQ. Our main objective is to have fun! There are a lot of people at the events and on the message board who are more than willing to help you. Just ask! Once you’ve driven in an event, you will probably be hooked!