I did some tire experiments this weekend.
We all know that if you use a tire a couple of times in a row, it gets all mushy and soft, and your car is all over the track. The 'rotating tire system' works, but I wanted to try something else.
* A rear tire (grey, granite) can be used twice in a row, easily. The third time is a bit sloppy, and the fourth time is time to get a new tre.
* Fronts can go a bit longer. About 5 runs. Because the compound is harder.
* If you clean the tires with motor cleaner between runs, you get more consistent traction. Maybe just a little bit more traction, maybe not, but in any case it's more consistent.
* If you coat the front tires only halfway across, make sure that the 'other half' also sees some traction compound. Even if it is for only 5 seconds, while you're wiping. If one half is completely dry and crusty, steering is too inconsistent.
When you take a 'fresh' tire, put additive on it, it will run very well, car will feel sharp and quick. But you can have more overall traction with a tire that has been run before.
The first time you put additive on a tire, you need to let it sit for at least 15 minutes. Take 20 minutes, to be on the safe side. For a tire that has been run before (on the same race day), this is much less. 5 minutes may be enough. 10 minutes is definitely enough.
You do not need to 'let it soak'! If you put gallons of traction compound on a tire, and let it soak for a long time, the traction compound will penetrate the foam, and make the entire tire soft and weak. This does give more traction, but it makes the tire much more prone to chunking. Plus, it feels 'sloppy' on the track. You would have been much better off with a softer compound tire with less traction compound!
Instead, I prefer this method:
The first time you use a tire, apply a coat of traction compound, but wipe most of it off. Let it sit for 20 to 30 minutes.
The second and third time you use that tire, apply traction compound, wipe it off very well, and let it sit for ... anything between 5 and 15 minutes. How long you let it sit isn't crtical anymore.
With this method, only the outer surface of the tire is soft. The inside is still firm, so the tire is well supported and resistent to chunking.
If a tire has had too much traction compound on it, and you want to use it again, you will have to let it dry out. So, you might want to begin with cleaning it with motor cleaner. If you wipe it, and your rag is still black, it's not clean yet.
You can let it air-dry, it will take a while for the inside of the foam to completely dry out. You can put them somewhere warm, like on top of your power supply, which does speed up the process. I've heard of people putting their tires on the stove for almost a week. I'm not sure if that's overkill or a good idea.
I've experimented with different traction compounds. CS Blue (medium traction), and CS yellow. (High traction) (www.cs-electronic.com
Yellow gives a lot of traction. Even more than Jack the gripper and LRP blue. It really 'sticks'. It is somewhat oily though, so it has a tendency to stay 'on' the tire instead of penetrating it.
Blue gives less 'stick', but it reduces traction rolls, and the car slides much easier. Really easy to drive. It also penetrates the tire the instant you apply it.
I found the best combination to be blue for the front tires, yellow for the rears. Plenty of forward traction, and very forgiving.