Goodyear Tires

[Young Gun]

Does anyone know the Goodyear durometer tire readings or where I can find them? I am trying to decide whether to race Goodyears or Hoosiers and would like some information.

[Young Gun]

Does anyone know the Goodyear durometer tire readings or where I can find them? I am trying to decide whether to race Goodyears or Hoosiers and would like some information.

[James Waltman]

You should find this link helpful:
http://www.millikenresearch.com/fsaettc.html

(Also, I suggest that you read the first two topics in the Open FSAE Discussion section. The ones in bold.)

[ben]

Durometer readings i.e. Shore A hardness (particularly at room temperature) is a poor indicator of grip unless you're comparing compounds of the same family.

Grip isn't just a function of hardness (we would indicate that using dynamic modulus - E*) it's also influenced by energy dissipation (measured by the tangent of the phase angle between stress and strain on a viscoelastic test).

Increasing tan delta generally increases E* for a given tensile strength. This means in practice you're always trading the two off against each other. Decreasing E*, increasing tan delta whilst maintaining tensile strength is the holy grail and the main thrust of a lot of compound testing.

I appreciate that a durometer reading is a cheap and easy measurement, but it's cheap and easy because it doesn't tell you a lot. Given that the TTC data is only $500 I'd use that as a basis for any objective decision regarding tyres, but even then you should seriously consider track testing different options because compound behaviour is always different on a real track surface. Plus the track surface itself will tell you where you need to bias your compromise between energy dissipation and softness.

Ben