Information: A rough guide to wheels

[nfbr]

Here's my guide to wheels and tyres. Basically just gonna let you all know whats what in the world of wheels... If theirs anything missing, let me know and I'll add it on!

Right, So lets start with OFFSET, I'm sure you've all heard of it. But what the hell is it?

Image1


This picture shows a wheel cut up. Basically, The offset, is the distance from the Center line of the wheel itself, to where the hub of your car is in contact to the wheel.
For example if the distance from the center line of the wheel to the hub contact surface is 18mm, it would be Offset ET18, On the other hand if it was 52mm, it would be ET52.

So basically the higher the number, the further away from the closer the spokes will be to the caliper


Next, I'll explain about PCD. PCD(pitch circle diameter) is the spacing of the stud/bolt holes on the wheels, and also denotes the number of studs/bolts per wheel.

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The first one in the picture shows a four stud, with these the PCD is measured between the center of one wheel nut hole, and the center of the one next to it. for example if in the picture above, the four wheel nuts were 100mm apart, This would be ETA 4x100
The second one in the picture shows a five stud, with these the PCD is measured between the center of one nut, and to the direct opposite of the pitch circle, its not to easy to explain but the picture makes things a bit more clear. If this distance was 110mm, then it would be ETA 5x110

Last part for wheels, is The Center Bore
The center bore is the bit of the wheel that the entire weight of the car is rested on. I'm sure if you've ever taken a wheel off you'll have seen the bit which sticks out of the hub making contact with the hole in a steel wheel, or the recess in an alloy wheel.

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The centre bore is pretty easily measured, between the two furthest points of the hole/recess. If this measures 60.1mm, then the Centre bore would quite simply be 60.1mm!

Stud Paterns that i know - (Any others you would like to know just ask)

4 Stud VW - 4x100
Some 4 Stud Audi - 4x100
Some 4 Stud Audi - 4x108

Early 5 Stud VW - 5x100 (Excl Mk5 Golf)
Later 5 Stud VW - 5x112
5 Stud Audi - 5x112 (Excl A2 and mk1 A3/TT)
5 Stud Mercedes - 5x112
5 Stud Porsche - 5x130

Center bores that I know - (same applies, shout me if there's any you want to know)

VW - 57.1mm
Porsche - 71.6mm
Fiat - 56.1mm
Vauxhall - 56.6mm
Renault - 60.1mm
Mercedes - 66.6mm

Edited December 29, 2016 by nfbr
Cleaned by: nfbr.