The Cf numbers represent the standard R4. Low to mid .5-.55 is a prettty darn good pad for many applications. Higher bite pads may not be needed and honestly they don't guarantee shorter stopping distances. Especially on street tires.
I'm guessing here but the R4s is probably in the .47-.48 range based only on my thoughts of what I'd put into this pad. Durability comes with less bite.
Running the R4 for a track pad is a great choice. They have served me well on many race applications. They are available for all the Wilwood apps also. I don't believe I'd run them on the street given wear and dust levels.
As for all out 'race pads' they come up a bit short. That's ok, they don't eat rotors like the Poly A's for example. Porterfield also stocks these same pads now under the Raybestos label. I believe A's are ST41 compound. Wilwood has the license to the Polymatrix wording but the pads are still Raybestos.
Last edited by Todd TCE; 05/03/04 02:24 PM.
