We used the following formula from the Toledo club
(pls correct me if I maje a mistake!!)
5 Gallons Methanol
32oz. Mountain Dew fountain syrup
32oz. Castor Oil
Depending on the grade of the concrete or asphalt, you can adjust the amount of Castor oil but we had INSASNE grip for foam and rubber tyre cars that lasted all weekend with just 1 sprayng, hope this helps!!
Greater L.A. R/C Racing Club