That sounds like the title for a Young Adult book, doesn’t it?
What the Heck IS PJ1 TrackBite?
NASCAR announced that they are again going to treat the corners of the track at New Hampshire International Speedway with a magic liquid called PJ1 Track Bite. The track enhancer has been used at Bristol (with great success) and at Charlotte and will likely be seen at more tracks in the future.
So what is this stuff and what does it do?
PJ1 TrackBite is common in the drag racing world. So common that every drag racing forum has at least one thread in which people discuss how to make your own. (It costs about $40 per gallon.)
There is always some clever person who suggests “Just look up the MSDS. It’s all there.”
MSDS is Material Safety Data Sheet, a government-mandated report that must be included when you buy hazardous chemicals and must detail what said hazardous chemicals are and how they should be safely handled and disposed of. Here’s the composition information from the first MSDS I found for PJ1 TrackBite.
Not exactly illuminating, but it turns out this one is from 2006, so I found a more recent one, from the company’s website.
Not real helpful and decidedly less ironic than the first one, huh?
The laundry list of chemicals (isopropanal, n-hexane, ehanol, hexane, methylcyclopentane and toluene) are all just solvents. They are carriers for the main (proprietary) ingredient. For example, nail polish is the actual stuff than ends up on your nails, suspended in solvents. The solvents allow you to apply the polish as a liquid; then, the solvent evaporates and leaves behind the actual nail enamel. So, even though it’s an impressive list of chemicals, they have nothing to do with how PJ1 Track Bite works.
That secret is entirely in the 10-20% of the product they don’t have to disclose because it’s not hazardous. The part that gives the Track its Bite.
So we are back to ground zero and we will just have to figure it out ourselves. Fine. I didn’t spent twelve years in college for nothing.
On the drag racing forum where people discuss how to make your own TrackBite, there is always at least one person who will suggest that you just just use soda because it works almost as well. You will also likely find someone who is militant about the merits of orange soda relative to cola.
These people are missing the point entirely. PJ1 TrackBite doesn’t work because it’s sticky. I bought some. (Yes, from Amazon; the shipping costs almost as much as the product if you buy it in small quantities, but I had no idea what I was going to do with a gallon of the stuff. Tracks buy it stuff in 55 gallon drums.)
The video below shows you that the consistency of this stuff is not very different from water.
It’s 80-90% solvents, so it ought to have the consistency of alcohol, right?
But even when it dries, it’s not all that sticky — it’s about the same level of stickiness as a sugary soda when dried.
It doesn’t work the same way that spraying soda in your pit box helps your pit crew not slip around. There’s a huge difference between the heat generated by the pit crew’s sneakers and the heat generated by the tires on a car going 190 mph.
Useless Fact involving PJ1 TrackBite and Gummi Bears: The forums all talk about the very particular smell of this stuff. The first smell that hits you when you open the bottle is alcohol — not surprising given the ingredients. It reminded me of rubber cement or mucilage. But when you let it dry, it starts to smell like gummi bears. Honest. It’s got a syrupy, almost sickly-sweet smell to it. If you’re going for smell, Gummi Bears are a better buy at about $3/lb.
Not-at-all Useless Safety Warning: It’s also extremely flammable because it’s mostly alcohols. One shouldn’t play with it indoors because it will give you a headache. One should also read the rest of the MSDS before one starts playing with it and not after one already has the headache. Don’t worry about safety for the drivers: It’s not at all flammable after it’s dried because the alcohol all evaporates.
If It’s Not Sticky, How Does It Work??
That’s really the interesting question. There isn’t a lot out there about this substance. I bet that everything you’ve read about it on NASCAR sites includes the following phrases:
- PJ1 TrackBite, formerly known as VHT TrackBite or simply VHT, is a custom formulated resin
- The compound originated as a high temperature coating made for NASA by the Sperex Corporation.
That’s all from the Wikipedia page and is a prime example of how you can sound very knowledgable on a topic without communicating any useful information.
The fact that it’s a resin is immaterial. A resin is simply a solid (or very viscous liquid) that can be polymerized. Polymerized just means a bunch of organic molecules that had been standing around by themselves hold hands. Shellac and lacquer are examples of resins: They go on liquid (gooey liquid) and then polymerize to make a hard coating. Amber is polymerized tree sap.
We can learn something, however, in the note about the material starting out as a high-temperature coating. High-temperature coatings are not sticky! They are hard and tough and usually brittle. The original work Sperex did with NASA was for the Space Shuttle. The company still sells high-temperature paint that you can use on your exhaust systems, firewalls, engine manifolds, etc. The picture below is from a NASA Technical Report from 1978 and I included it just because it shows the legendary drag racer Carol “Bunny” Burkett, whom I was shocked to find does not have a Wikipedia page.
The hard thing about high-temperature coatings that they not only have to survive high temperatures, they have to stick to whatever they are coating – and the picture at right shows that can be a problem even when the high-temperature you’re talking about is just a really hot summer.
When you make a peanut butter sandwich, you ever notice how the peanut butter would often rather stick to itself than the bread? The paint in the picture is doing exactly that. It’s spalling: it would rather stick to itself than the brick.
Rubber is the same way. Rubber will stick to asphalt, but it would much rather stick to rubber. The proof of that is the marbles you find at the edge of the track and the coating of rubber pieces found on tires, bodies, walls, etc. after a race.
Understanding Grip on an Atomic Level
You know a rubbered-up track has better grip than a non-rubbered-up track because you lose grip when it rains and the rubber washes off the track. But do you know why a track rubbers up? Here’s why:
- Friction, at it’s most fundamental, is the atoms of one surface grabbing the atoms of another surface and trying to form an atomic-level bond. When you put tape on paper, sometimes the bond is so good that you can’t remove the tape without taking some of the paper with it.
- As mentioned before, most things like sticking to themselves more than they like sticking to other things.
- When race tires are warm enough and the track is warm enough, the rubber at the tire surface softens; think of it as the links between rubber molecules going from a fireman’s grip to linking pinkies. The rubber molecules already on the track are similarly warm, and when the warm tire-rubber molecule get close to the warm rubber-on-the-track molecule, they can form a bond. That bond is called adhesive friction.
- Think of adhesive friction like this: Say you’re walking down the sidewalk in your tennis shoes on a very warm day. You step on a giant piece of gum. That’s gonna slow you down, right? Friction. The rubber in the track does the same thing: each rubber-rubber bond made (and then broken) helps the car grip the track. (This is why it’s so important to warm up your tires. If the tires are too cold, the rubber atoms in the tire hang onto each other and don’t interact with the track. That’s what no grip means on an atomic level.
- Obviously, bonds are always being broken, or the cars would get stuck in the track like a saber-toothed tiger in the LaBrea Tar Pits. Sometimes the rubber from the track gets picked up by the tires. Sometimes rubber from the tires gets deposited on the track.
How PJ1 TrackBite Increases Grip
Looking at the instructions for application to oval tracks gives us some clues. As with any painting job, surface prep is more important than the actual application of the stuff.
- Clean the racing surface of dust, dirt, gravel and oil. In fact, they say “Clean, clean, clean the racing surface”. They also suggest Tide powdered laundry detergent as the best way to accomplish this cleaning step.
- Drag the track with a tire drag (using a tractor of at least 45 horsepower!). This is the single best thing to do to clean the racing lines.
- Sweep/power broom and blow off the track.
You can see immediately how the Tire Dragon and the Air Titan facilitate the process of using the TrackBite. NASCAR had been using the Air Titan for track conditioning well before the TrackBite idea ever got started.
After you’ve got a clean track, you spray on the Track Bite with the aforementioned #6 nozzles and let it dry. Drag some more tires over it. Reapply a light coat the morning of the event.
Here’s the key: TrackBite doesn’t stick the tires to the track better: It encourages rubber from tires (those on the race car or those being dragged) to stick to the track better, which makes the track rubber up faster and stay rubbered up longer.
A Possible Competitive Advantage?
Racers look for every possible advantage. Even things we think are too small to be important don’t get ignored in NASCAR because the competition is just that tight.
There’s an interesting note at the end of the application instructions.
TrackBite isn’t water-soluble. That’s good because rain won’t wash it off the track; but most things that aren’t soluble in water are soluble in oil, which suggests to me that any oily fluid leaking from a car probably degrades the TrackBite in that area. So if there’s a crash, the spotters may need to carefully note where the spill happened because even after they’ve removed the oil from the track, there may be less (or no) TrackBite in that area and the grip of that particular section of track might be significantly different that the rest of the track.
Something to think about when you’re watching the race this weekend.