Technical Information

Before buying a set of alloy wheels,it will be helpful to read some technical information about alloy wheels.There are many buyers who end up buying wrong set of wheels due to lack of knowledge. Therefore some basic information can come very handy before the purchase.

To have a proper stance, you need to know a few technical details about alloy wheels. First one is PCD which is one of the most important details of an alloy wheel.

WHAT IS PCD?

PCD stands for "Pitch Circle Diameter" which is the diameter of circle that goes through the center of the bolt holes.

As you can see above in the picture,we draw a red imaginary circle to indicate PCD.PCD value also gives us the number of bolts which is also essential for the correct fitment.For a wheel to fit properly on to a hub,the PCDs have to match exactly.

Every car brand and model have different PCD values,Before the purchase make sure your new alloy wheels have the correct PCD value for the perfect fitment.

As an example: If you have a Volkswagen Golf,your original PCD would be 4x100. "4" gives us the number of studs,"100" gives us the diameter of the studs from the centre of the wheel.In this case, your new volkswagen alloy wheels must be 4x100.

Common PCDs are 4x108(Ford), 4x100 (Honda/VW/Mazda/Rover), 4x98 (Fiat,Alfa),4x114.3 (Toyota/Rover/Honda),5x100 (VW/Audi), 5x112 (Audi/Mercedes),5x114.3 (Honda,Nissan).

You may not know the specs of your car but we know.So if you want to know the correct fitment for your car,you can either see our fitment guide or contact us and we will tell what specs you will need.

See the specs of your vehicle in our fitment guide!


OFFSET (ET):

Offset is the second important detail you have to be aware of before you buy new alloy wheels.ET is the distance between the imaginary centreline of the wheel(measured in mmm.) and the hub mounting face at the back of the wheel.Please examine the below picture to understand better.

Keeping the existing offset on your vehicle is ideal for preventing problems with loading on the bearings, and suspension effects.To fit alloys with smaller or bigger ET values may cause problems handling problems.The steering may become to light so it would be hard to control the car or it may be too heavy to turn the car.However there is a tolerance value in ET value.

Realistically you can go 5 mm outside these recommendations.We will not recommend going beyond these limits.Fitting wheels with beyond the limits will cause vibrations on the wheels which will also affect the handling,performance and more importantly the safety of the car.

To provide the perfect fitting,we supply spigot rings with our alloy wheels.


SPIGOT RINGS:

Spigot rings are special rings that are fitted to the centre of the hub in order to decrease the size of the bore.These rings are commonly used when buying a new set of aftermarket alloy wheels.

Aftermarket alloy wheels are manufactured with standart specifications including the bore size.So if you are buying a new set of alloy wheels,you better make sure that the bore size of your new wheels is correct size for the vehicle.

Click here to see our store for spigot rings!

In some cases buyers fit the wheels on cars without checking if the fitment is correct or not.This is a very big mistake!

If wheels do not locate on the centre hub then all the pressure is put on the bolts which in some cases you can get the bolts broken and your wheels come off.

Therefore it is extremely important to ensure the alloy wheel is centred correctly on a hub of a vehicle.

We can provide spigot rings with your new alloy wheels if you require.If you are not sure whether you need them or not,please contact us via e-mail and we can provide you more technical information.

A DEMONSTRATION ON HOW TO FIT SPIGOT RINGS ON AN AFTERMARKET ALLOY WHEELS

In this application, we have a 4x98 alloy wheel to fit a Fiat Punto. Most aftermarket wheels are made with a large centre bore so that they can be fitted on various makes and models. Our aftermarket wheels generally have a centre bore size of 67.1 mm. This is the diameter of the center hole where the wheel sits on the hub.

Now, since we are fitting these wheels onto a Fiat Punto. We need to get the center bore size down to 58.1 mm as the hub size of Punto is 58.1 mm.

For this reason, we will use spigot rings. Outer size of the rings we are using has to be 67.1 mm and inner size has to be 58.1 mm. Once we fit the rings on the wheel, the alloy is ready to go on the car. As we now have taken the bore size down to 58.1 mm, alloys will fit perfectly on the hub and provides an excellent ride without any kind of vibrations.

spigot rings

fitting spigot rings

hub rings

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