The most important element of wheel manufacture is the bolt pattern or ‘PCD’ (pitch circle diameter) of the wheel. The bolt pattern of the wheel must mirror the bolt pattern of the vehicle to ensure the wheel nut or bolt seats align and mate across the seating surface of the nut or bolt seats in the wheel. – See more at: http://www.speedywheels.com.au/accessories/what-is-wheel-pcd/#sthash.cpZ8Ecmz.dpuf
Correct mating seats and correct torque settings ensure that wheel nuts and bolts remain tight during service. You will normally see a PCD measurement as number of bolts x diameter in millimetres. Common sizes between vehicle makes include: 4x100mm, 5x100mm, 5×114.3mm and 5/120. In the case of 4WDs, 5/150, 6/114.3 and 6/139.7.
It can also be common to see multi hole PCD configurations, mostly for light passenger cars, such as 4/100-114.3mm (8 hole) or 5/100-114.3mm (10 hole).
Some distributors carry multi hole wheels to reduce stock inventory levels.
With so many vehicle manufacturers and model ranges, knowing what car has what PCD can get confusing and be difficult to confirm. In fact, one vehicle model can have two different PCD configurations, dependant upon engine size or type. Simplest way to check is to search online using our Wheel Magician database tool.
There are many different PCD configurations, so it is important to know how the PCD measurement is determined. To measure the PCD of a wheel or hub with an even number of bolts or bolt holes, simply measure the distance between the centre of two wheel studs or bolt holes which are directly opposing each other (not next to each other). On a wheel with five bolt holes, take the distance between the centre of two adjacent bolts or bolt holes, then multiply it by 1.701.
This resulting measurement is the diameter of the arc which encircles the centre of the five wheel studs or nut holes. To coincide with our next new product release for 2016, Speedy will offer an affordable PCD measuring tool as part of our accessory range. This very useful tool will be able to be purchased directly off the Speedy website from within the accessories page.
In the past, some wheel distributors and retailers have used either multi-fit (wobbly) nuts and or hub adaptors to enable a wheel PCD to be altered in order to adapt to a vehicle for which the wheel PCD drilling was not originally intended for.
Under the National Code of Practice (NCOP) guidelines, this process is now considered illegal throughout Australia and as such, should not be undertaken.
Wheel centre bore specifications should also not be overlooked when purchasing aftermarket wheels if the wheel centre bore diameter is less than your hub spigot diameter, then the wheel won’t fit onto your vehicle. If the wheel centre bore diameter is larger than the vehicle’s hub diameter, then it may be possible to source centre bore locating rings to centralise the wheel onto the hub and eliminate potential steering vibration at speed. Speedy supplies a range of these CBL rings in various external and internal diameters for use with alloy wheels as part of our accessory products range.
The bore hole diameter on some wheels can be safely altered or enlarged by machining – though this will need to be carried out by a qualified wheel specialist.
Speedy undertakes this special work in our Sydney machining facility, but only to those alloy wheel products marketed and underwritten by the company.
– See more at: http://www.speedywheels.com.au/accessories/what-is-wheel-pcd/#sthash.cpZ8Ecmz.dpuf