VWW Official MKIV Wheel Q&A

**dylan8** · 05-09-2012, 02:09 PM

Basically I thought I would make a thread that assists in fitting wheels to a mk4.
We have a few random threads floating around but some of the info is misleading/missing.
I currently contribute to a few over seas ones and they work well most of the time if people take a step back and learn the basics, it makes it very easy for others to help out and answer any questions.

I want to include guide to wheels, index of other fitments done in AUS, and then allow for people to ask questions or post up there own so I can add them to the library/index.
This is not just for 'fitted/stanced' cars, it needs everything from stock wheels and stock heights

I will be taking some information from other sites, but if we can keep the library to Aussie mk4s itll be very helpful.

In typical 'tex fashion. VWW, myself, and anyone else who posted in this thread are not responsible for anything (broken arches, defects, loss of income etc). While I hope none of this happens, this is a guide to be used at your own discretion and common sense.

**dylan8** · 05-09-2012, 02:10 PM

Thanks to Pat at uk-mkivs.net

If you do have a question, please give the following information:

Wheel width (front and rear)
Wheel offset (front and rear)

Without these 2 figures, it's impossible to say how the wheel will sit in relation to the arches.

Desired ride height's also useful to know.
On a mk4, at the front up until ~70mm lower than standard the amount of poke stays the same.
After this point the front sucks in at the top, (kind of cambers in) and will affect the final amount of poke.
The rear, being a single beam, stays the same no matter what the final height.
4wd mk4's are different again, as they have independent rear suspension (IRS). Lowering can be likened to lowering the front (ie, the wheel will start to camber in, the lower the car is)
I'll post pictures to demonstrate this.

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Another thing to remember. On a mk4, the rear track is around 8-10mm less per side than the front. Therefore, if you fit some 10mm spacers at the rear, it will sit in line with the arch exactly the same as the front. So if you're running standard wheels and want a reasonable cheap aesthetic fix, get some 8-10mm spacers on the back. It'll improve the look without costing a bomb.

If you're wanting to run staggered wheels, this can work to your advantage. If your front wheel is 8j et25, and the rear is 9j et25, then the rear will sit just 3mm further out than the front (10mm less, but 1/2" (12.7mm) wider each side of the centre)

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Measuring a wheel:

It's amazing how many people do not know that a wheel measures an inch larger, both in diameter and in width than it's specified. For example, when you put a measuring stick on a 15x7j wheel, it'll actually measure 16" in diameter and 8" in width. This is because the bead is not included in the measurement and is 1/2" top and bottom, and 1/2" at each rim = 1" extra all round

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How to measure a wheel's offset:

Although most wheels will have stamps on them somewhere (rear of spokes for example), some won't. The offset is described by the term ET, which is from the German word 'Einpresstiefe' translated as 'insertion depth'. You'll see it stamped, ET** or **ET (** = number)

Anyway, this is made a lot easier if you have the wheel in front of you without a tyre fitted, but is possible if the tyre's still on it.

Get a straight edge, ie a steel ruler or strip of straight cut wood and a measuring tape.

1) Measure the entire width of the wheel. If it's an 8j wheel, it'll measure 9" across from outside of the bead to outside of the bead (A in the diagram above) I'll use this as an example here. The example wheel will have an positive offset (et) of 35mm.

and inside bead to inside bead, it's 8"

2) Place the steel ruler flat across the rear of the wheel

3) Using the tape, measure from the mounting face where the wheel sits on the hub to the edge of your steel rule. Make a note of it. This measurement is the backspace (B). In this example it's 149mm

4) Convert the measurement of the total wheel width (A) to millimetres. In this case it'd be 9 x 25.4 = 228.6mm
5) Divide it by 2, = 114.3mm
6) Take the backspace measurement (B) that you got in point 3, and deduct the measurement you got in point 5, eg: 149mm - 114.3mm = 34.7mm This is the offset of the wheel. In this example this makes ~35mm
7) If the tyre's still fitted to the wheel and has stretch, it's likely you'll still be able to do this with no problem. However, if the tyre's not stretched and protrudes out further than the rim then you'll need to make your straight edge in point 1 the same length as the diameter of the wheel, so that it sits on the rim, to get an accurate measurement. A strip of wood cut to length would do nicely

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Some links containing very good information

Clicky: Wheel Offset Calculator
Clicky: How to measure multi-piece wheels, lips, barrels etc
Clicky: Final calculations after lip and / or barrel change
Clicky: Tyre stretch thread with quite a few example pictures
Clicky: vwvortex mk4 wheel offset and stance picture index
Clicky: vwvortex Tyre stretch master thread with examples

**dylan8** · 05-09-2012, 02:10 PM

Differences between MKIV models affecting fitment

Track difference
Brake sizes
Driveshaft sizes and lows
Sway bars

**dylan8** · 05-09-2012, 02:11 PM

List of standard wheels and tyre sizes from factory for MKIV

1.6lt:
14"

My 2lt had:
195/65/15 on 15x6et38
205/55/16 on 16x6.5et42
225/45/17 on 17x7et38

R32:
225/40/18 on 18x7.5et38

**dylan8** · 05-09-2012, 02:11 PM

AWD and staggered tyres/widths

Originally Posted by kapowww

Had no problems at all with a staggered setup.

Have a read of this thread: http://www.vwwatercooled.org.au/foru...ion-60616.html

Basically widths and offsets don't affect the Haldex in the 4motion as the Haldex just cares about wheel slippage. Rolling circumference of the tyre is what can throw it off, although the Haldex controller is programmed to accept variable rolling circumferences and deal with it. On one forum someone said (don't quote me on this) that the maximum difference is 4% which is a pretty huge difference anyway.

In terms of increasing the rear track more than the front I honestly didn't pay attention so can't answer that.

**dylan8** · 05-09-2012, 02:11 PM

if people layed it out like below, i think it would be helpful, as there are too many variables.
and if not all info is supplied its a pointless exercise.

Example:
Car: FWD or AWD
Front: 18x8.5 et30 215/40/18
Rear: 18x9 et30 225/40/18
Arch height to ground Front: 24"
Arch height to ground Rear: 24"
Fenders Rolled: Yes
Fenders Pulled: No
Camber: Front No / 1deg extra in rear
Photo 1: showing height of car
Photo 2: showing poke/fitment in relation to the guards

**dylan8** · 05-09-2012, 02:12 PM

The VWW MKIV Library

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** 15" Wheels **
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15x6

15x6.5

15x7

15x7.5

15x8

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** 16" Wheels **
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16x6.5
Front et43 dylan8
Rear et43 dylan8

16x7

16x7.5

16x8

16x8.5

16x9