Technical

Stud Patterns / PCD

PCD stands for Pitch Circle Diameter usually expressed in millimetres. The centre of every bolt lies on the circumference of the bolt circle. The following image below shows how to measure the PCD. For a 4 or 6 bolt car, this measurement is merely the distance between the centre of two diametrically opposite bolts.

 

 

 

 

 

 

Tyre Basics – How to read your tyre size

Tyres have a code system moulded into their sidewall which allows you to understand their technical capabilities. This code provides information on the tyre’s construction (e.g. radial), its size, its load-carrying capacity and its speed rating. For example, the code on a common fitment for Australian cars is: 205/65R15 95H