SCCA Solo car number size requirements?
01-29-2009, 02:14 AM
#1
Le Mans Master
Thread Starter
SCCA Solo car number size requirements?
I'm getting ready to buy a number set, and I wondered what size was required - I was digging out the GCR when I figured someone here would know off the top of their head 
THANKS!
THANKS!
01-29-2009, 06:46 AM
#2
Le Mans Master
if I remember correctly, the #s need to be a min. of 8" high, and 1" thick strokes them, and the letters must be 4" with the same stroke.
Last year in Topeka, after running the same #s for the past 3 years, they said "sir, you'r #s failed tech... they're 1/4" too small..."
I think mine were 7 3/4" high.
Luckily since my car was black, and the #s were white, they felt they were still readable.
Last year in Topeka, after running the same #s for the past 3 years, they said "sir, you'r #s failed tech... they're 1/4" too small..."
I think mine were 7 3/4" high.
Luckily since my car was black, and the #s were white, they felt they were still readable.
01-29-2009, 07:26 AM
#3
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01-29-2009, 10:01 AM
#4
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The short answer:
Numbers must be a minimum of 8" high with a 1.25" stroke. Class letters must be a minimum of 4" high with a 0.75" stroke. In all cases, the height of the class letters must be between 25% and 75% of the height of the numbers. Stroke width must be at least 10% of the height. (Straight from the rules)
This is a post/write-up I did for our local SCCA Region a few months ago:
What defines a racecar?
Is it a roll bar? No, Police cars have those.
Stickers showing off the parts you have on the car? Nah, show cars have those in spades.
Want to know?
Drive a car by a school bus full of elementary school kids and they will let you know when.
So when is it?
It’s when the number dominates the car.
There is a reason why the #3 is synonymous with Dale Earnhardt Sr. Why when I say “the #43” and you think of Richard Petty. It’s why the #14 has been reserved for the use of AJ Foyt in IndyCar racing.
So it stands to reason that if you want your car to work as a competition vehicle when autocrossing you should have very visible numbers on the side of it. (Oh.. and it’s in the rules as well.)
The SCCA Solo Events rule book has an entire section on numbers, and even a clarification in the appendix.
So let’s break down Section 3.7 – VEHICLE IDENTIFICATION:
What this means is what it says - All cars must have numbers and class letters on both sides, and they must be able to be read by timing and scoring along with course workers. “Able to be read” is defined more in depth later.
This means that you can’t have another set of numbers on the car.. like “14ES” if you are registered as “14ASP”
Hey.. that one is even spelled out for you. I am not going to bother explaining. (I will mention that I have seen something like, “45 TIR” for street-tire classes. Which, by the rules doesn’t work. (sorry no picture of that)
Let’s break this one down, because it seems to be one of the more misunderstood…
Numbers and class letters should be next to each other. Adjacent to. Not numbers on the door and letters on the window, or fenders, or, well.. anywhere else.
Where are the class letters? Is XP the sponsor or the class? See the problem?
All letters and numbers must be on body panels, not on windows.
This doesn’t work.
All letters must have matching typeface (font) and color: See the example above with the “XP” not having a matching typeface just adds to the confusion.
Colors must provide contrast to the background color. Dark colors on a dark color doesn’t work, light colors on a light car doesn’t work… (As I have heard said, red is dark, black is dark.. so red and black doesn’t work)
I hope I don’t have to explain this example, and even though it was probably put on by tech, it still doesn’t work – this is why tech should have some purple masking tape.
At least the class letters are ok.. but white on silver.. yea.. that’s just not working.
This one didn’t pass tech at the 2008 SCCA Solo National Championships – so if you THINK it might work, you might want to go one extra step to be sure.
One of the worst examples I have ever seen.
This one is the one you get to do math with. When we work tech at national events, this is where we come out with little rulers and such.
Don’t let anyone ever tell you size doesn’t matter. (At least in the case of numbers on racecars) The bigger it is, the easier it is to read. Notice these example pictures are kind of small – I did that on purpose. If you want a good test, take a picture of your car, resize it to thumbnail size. Show it to someone who has never seen it before for less than one second. If they can’t tell you what number it is, go back and order new numbers. (If you haven’t ordered numbers yet.. well.. make sure you wont have to order new ones, they can be expensive)
Example one.. class letters too large. It is readable, but it isn’t right, and at a glance it is good to have the different sizes.
Think this one will pass my thumbnail test?
For reference, here is the image used in the SCCA Appendix:
We also see this one violated at local events. I will dig up some pictures and update the thread.. Essentially though, putting the “L” or “P” or “T” somewhere far away from the number and class letters doesn’t help anything..
This one explains the rule for karts.. so it won’t apply to most of us. But you see there is still a lot of attention paid to being able to see the number.
Finally, some good examples:
To prove that it can be done in tape – good size, correct ratio for numbers:letters.. the stroke isn’t really enough, but for a local event, it isn’t horrible:
Dark numbers on a light background:
Light numbers on a dark background:
More light numbers on a dark background:
Of course, sometimes you don’t want to have a lot of different numbers and letters to keep track of, so you want a single-piece number plate – here are a couple that work:
So hopefully that helps…
Take this time to make sure your numbers are ok. Remember, you can’t have an SCR-SCCA annual tech without SCCA Nationals-spec numbers. Make sure that you are not the cause of a numbers-related delay or scoring problem.
Then, once you get them right, drive by an elementary school and watch the kids pointing and cheering.
Jon K
Numbers must be a minimum of 8" high with a 1.25" stroke. Class letters must be a minimum of 4" high with a 0.75" stroke. In all cases, the height of the class letters must be between 25% and 75% of the height of the numbers. Stroke width must be at least 10% of the height. (Straight from the rules)
This is a post/write-up I did for our local SCCA Region a few months ago:
What defines a racecar?
Is it a roll bar? No, Police cars have those.
Stickers showing off the parts you have on the car? Nah, show cars have those in spades.
Want to know?
Drive a car by a school bus full of elementary school kids and they will let you know when.
So when is it?
It’s when the number dominates the car.
There is a reason why the #3 is synonymous with Dale Earnhardt Sr. Why when I say “the #43” and you think of Richard Petty. It’s why the #14 has been reserved for the use of AJ Foyt in IndyCar racing.
So it stands to reason that if you want your car to work as a competition vehicle when autocrossing you should have very visible numbers on the side of it. (Oh.. and it’s in the rules as well.)
The SCCA Solo Events rule book has an entire section on numbers, and even a clarification in the appendix.
So let’s break down Section 3.7 – VEHICLE IDENTIFICATION:
SCCA National Solo Rules wrote:
3.7.A: All vehicles must display numbers and class letters on both sides, which must be readable by Timing & Scoring, Course, and Grid workers at all times.
3.7.A: All vehicles must display numbers and class letters on both sides, which must be readable by Timing & Scoring, Course, and Grid workers at all times.
SCCA National Solo Rules wrote:
3.7.B: Only one set of numbers and class letters may be visible while the vehicle is running.
3.7.B: Only one set of numbers and class letters may be visible while the vehicle is running.
SCCA National Solo Rules wrote:
C. Class shall be represented by the upper-case abbreviated form rather than be spelled out. Ladies’ classes shall be indicated by the letter “L” following the class letters. (Example: “BSPL” instead of “B Street Prepared Ladies”).
C. Class shall be represented by the upper-case abbreviated form rather than be spelled out. Ladies’ classes shall be indicated by the letter “L” following the class letters. (Example: “BSPL” instead of “B Street Prepared Ladies”).
SCCA National Solo Rules wrote:
D. Numbers and class letters should be positioned next to each other. All letters and numbers must be on body panels, not on windows. All numbers and class letters must use the same typeface and the same color, and this color must provide adequate contrast to the background color (see Appendix F for examples).
D. Numbers and class letters should be positioned next to each other. All letters and numbers must be on body panels, not on windows. All numbers and class letters must use the same typeface and the same color, and this color must provide adequate contrast to the background color (see Appendix F for examples).
Numbers and class letters should be next to each other. Adjacent to. Not numbers on the door and letters on the window, or fenders, or, well.. anywhere else.
Where are the class letters? Is XP the sponsor or the class? See the problem?
All letters and numbers must be on body panels, not on windows.
This doesn’t work.
All letters must have matching typeface (font) and color: See the example above with the “XP” not having a matching typeface just adds to the confusion.
Colors must provide contrast to the background color. Dark colors on a dark color doesn’t work, light colors on a light car doesn’t work… (As I have heard said, red is dark, black is dark.. so red and black doesn’t work)
I hope I don’t have to explain this example, and even though it was probably put on by tech, it still doesn’t work – this is why tech should have some purple masking tape.
At least the class letters are ok.. but white on silver.. yea.. that’s just not working.
This one didn’t pass tech at the 2008 SCCA Solo National Championships – so if you THINK it might work, you might want to go one extra step to be sure.
One of the worst examples I have ever seen.
SCCA National Solo Rules wrote:
E. Numbers must be a minimum of 8" high with a 1.25" stroke. Class letters must be a minimum of 4" high with a 0.75" stroke. In all cases, the height of the class letters must be between 25% and 75% of the height of the numbers. Stroke width must be at least 10% of the height. (See Appendix F.)
E. Numbers must be a minimum of 8" high with a 1.25" stroke. Class letters must be a minimum of 4" high with a 0.75" stroke. In all cases, the height of the class letters must be between 25% and 75% of the height of the numbers. Stroke width must be at least 10% of the height. (See Appendix F.)
Don’t let anyone ever tell you size doesn’t matter. (At least in the case of numbers on racecars) The bigger it is, the easier it is to read. Notice these example pictures are kind of small – I did that on purpose. If you want a good test, take a picture of your car, resize it to thumbnail size. Show it to someone who has never seen it before for less than one second. If they can’t tell you what number it is, go back and order new numbers. (If you haven’t ordered numbers yet.. well.. make sure you wont have to order new ones, they can be expensive)
Example one.. class letters too large. It is readable, but it isn’t right, and at a glance it is good to have the different sizes.
Think this one will pass my thumbnail test?
For reference, here is the image used in the SCCA Appendix:
SCCA National Solo Rules wrote:
F. The “1” on two-driver cars and the “L” on Ladies class cars are subject to all of the above requirements with regard to placement, color, size, and stroke.
F. The “1” on two-driver cars and the “L” on Ladies class cars are subject to all of the above requirements with regard to placement, color, size, and stroke.
SCCA National Solo Rules wrote:
G. Karts may use numbers and class letters of reduced size provided that the following conditions are met: 1) Numbers must be displayed on the front and rear in addition to both sides; 2) Class letters must be on both sides; 3) In no case may the numbers be smaller than 6" in height with ¾” stroke, using a high-contrast color and background.
G. Karts may use numbers and class letters of reduced size provided that the following conditions are met: 1) Numbers must be displayed on the front and rear in addition to both sides; 2) Class letters must be on both sides; 3) In no case may the numbers be smaller than 6" in height with ¾” stroke, using a high-contrast color and background.
Finally, some good examples:
To prove that it can be done in tape – good size, correct ratio for numbers:letters.. the stroke isn’t really enough, but for a local event, it isn’t horrible:
Dark numbers on a light background:
Light numbers on a dark background:
More light numbers on a dark background:
Of course, sometimes you don’t want to have a lot of different numbers and letters to keep track of, so you want a single-piece number plate – here are a couple that work:
So hopefully that helps…
Take this time to make sure your numbers are ok. Remember, you can’t have an SCR-SCCA annual tech without SCCA Nationals-spec numbers. Make sure that you are not the cause of a numbers-related delay or scoring problem.
Then, once you get them right, drive by an elementary school and watch the kids pointing and cheering.
Jon K
01-29-2009, 01:37 PM
#7
Le Mans Master
Thread Starter
I bought the reusable vinyl numbers:
- 2 sets of 8" numbers, block, opposite slants
- 2 sets of 4" class letters (SS), block, opposite slants
- 2 chunks of material to put stickers on
http://www.soloperformance.com/Solot...et_p_1380.html
- 2 sets of 8" numbers, block, opposite slants
- 2 sets of 4" class letters (SS), block, opposite slants
- 2 chunks of material to put stickers on
http://www.soloperformance.com/Solot...et_p_1380.html
Last edited by billla; 01-29-2009 at 01:44 PM.
01-29-2009, 07:22 PM
#8
Team Owner
Most sign/graphics shops can make static cling number sets
I got my numbers done in black on a clear background. The cost was $40 for a pair and they came on a plastic-coated sheet for storage. The shop said they could use any Windows True-Type font and I had a choice of somewhere around 20 colors.
Static cling sets will work fine for autocross but they probably won't stay on for high-speed events like track days. Reusable adhesive vinyl works best for that but from what I have read, the adhesive can stand only so many applications for it begins to lose its effectiveness.
I got my numbers done in black on a clear background. The cost was $40 for a pair and they came on a plastic-coated sheet for storage. The shop said they could use any Windows True-Type font and I had a choice of somewhere around 20 colors.
Static cling sets will work fine for autocross but they probably won't stay on for high-speed events like track days. Reusable adhesive vinyl works best for that but from what I have read, the adhesive can stand only so many applications for it begins to lose its effectiveness.
01-29-2009, 07:38 PM
#9
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This helps me too. Thanks.
My SS were the correct size at 4 inches, but my 586 is only 7". That's OK for where I run locally. I have to make new ones for Dixie anyway, as I have a different number.
Also, I know I'm missing the front Hoosier Sticker. Stickers are on the way.
In case you are wondering, mine are made of a 3XL T-shirt.
The Pfadt logo and the car number/class are printed on a 16" x 40" piece of black shirt, affixed to the car under contact paper. I use the contact paper to prevent rock chips from the sticky tires. (Note: The rocker panel in this picture did not have the contact paper installed yet.)
My SS were the correct size at 4 inches, but my 586 is only 7". That's OK for where I run locally. I have to make new ones for Dixie anyway, as I have a different number.
Also, I know I'm missing the front Hoosier Sticker. Stickers are on the way.
In case you are wondering, mine are made of a 3XL T-shirt.
The Pfadt logo and the car number/class are printed on a 16" x 40" piece of black shirt, affixed to the car under contact paper. I use the contact paper to prevent rock chips from the sticky tires. (Note: The rocker panel in this picture did not have the contact paper installed yet.)
Last edited by Datawiz; 01-29-2009 at 07:47 PM.
01-29-2009, 08:49 PM
#10
Le Mans Master
Yes, I'll be ordering a set of #s this year from solotime as well, and are going to use the re-usable adhesive. You're garunteed to get good #s from them since they've been doing this a while adn also that they're a sponsor of the SCCA and merch partner now.
I'm buying a yellow sheet of is as well to put my Hoosier decals on since they are not fun to remove ( at least the white ones sucked trying to get those of black cars ) and I don't want to take any chances. The mandated SCCA ones will go on that as well since i'm already buying a sheet.
BTW.. racerjon... GREAT writeup there.! I wish more people saw that locally...
I'm buying a yellow sheet of is as well to put my Hoosier decals on since they are not fun to remove ( at least the white ones sucked trying to get those of black cars ) and I don't want to take any chances. The mandated SCCA ones will go on that as well since i'm already buying a sheet.
BTW.. racerjon... GREAT writeup there.! I wish more people saw that locally...
01-29-2009, 09:22 PM
#11
Racer
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Location: North Richland Hills Texas
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In case you are wondering, mine are made of a 3XL T-shirt. The Pfadt logo and the car number/class are printed on a 16" x 40" piece of black shirt, affixed to the car under contact paper. I use the contact paper to prevent rock chips from the sticky tires. (Note: The rocker panel in this picture did not have the contact paper installed yet.)
The Pfadt logo and the car number/class are printed on a 16" x 40" piece of black shirt, affixed to the car under contact paper. I use the contact paper to prevent rock chips from the sticky tires. (Note: The rocker panel in this picture did not have the contact paper installed yet.)
What do you have wrapped around and inside the front fender well?
01-30-2009, 09:53 AM
#15
I bought 10" reusable vinyl outline numbers/letters from here:
http://www.izoomgraphics.com/index.p...=index&cPath=1
haven't used them in competition yet, but they looked great in the garage...
http://www.izoomgraphics.com/index.p...=index&cPath=1
haven't used them in competition yet, but they looked great in the garage...
01-30-2009, 10:55 AM
#16
Burning Brakes
For those that don't want to leave temporary, event-specific stickers attached directly to your paint after an event -
Here's a trick I've always used when given stickers at event registration that I don't have time to do anything else with other then just stick it directly to the car (like a TireRack windshield header or Hoosier stickers) ----
Take the sticker off it's backing and stick it to your SHIRT before applying to the car. It will grab a lot of lint from your shirt, reducing the stickyness of the adhesive just enough so that the sticker will stay attached to the car through the weekend, -BUT- it will be MUCH easier to remove at the end of the event. It has less chance to leave adhesive on the paint after removal on a hot day as well.
Some people look at me like I'm nuts when they see me do this in the pits, but when they understand why I'm doing it, they usually say "Man, I gotta do that, too!".
Here's a trick I've always used when given stickers at event registration that I don't have time to do anything else with other then just stick it directly to the car (like a TireRack windshield header or Hoosier stickers) ----
Take the sticker off it's backing and stick it to your SHIRT before applying to the car. It will grab a lot of lint from your shirt, reducing the stickyness of the adhesive just enough so that the sticker will stay attached to the car through the weekend, -BUT- it will be MUCH easier to remove at the end of the event. It has less chance to leave adhesive on the paint after removal on a hot day as well.
Some people look at me like I'm nuts when they see me do this in the pits, but when they understand why I'm doing it, they usually say "Man, I gotta do that, too!".
01-30-2009, 11:49 AM
#17
Le Mans Master
Thread Starter
01-30-2009, 11:51 AM
#18
Le Mans Master
Thread Starter
I bought 10" reusable vinyl outline numbers/letters from here:
http://www.izoomgraphics.com/index.p...=index&cPath=1
http://www.izoomgraphics.com/index.p...=index&cPath=1
01-30-2009, 12:25 PM
#19
true...but paying for the vinyl may be worth it if it's a sticker you need to put on/off mulitple times that's what I'm going to do for the nat'l autox event decals this season
03-05-2009, 04:56 PM
#20
Race Director
Crystalracer, how did that "low-tack" vinyl I gave you work? I haven't stocked up yet (as said above it is expensive), but it is handy for autocrossers. If what I gave you isn't the same as solotime sells, then I have no idea what they are using.
btw, I still have your helmet banner sitting here.....collecting dust...sorry.
btw, I still have your helmet banner sitting here.....collecting dust...sorry.