Tracking and Camber are shrouded in mystery by some, yet are can be very simple to measure at home. Nic Bowman Shares with us his document which shows you how to measure both using only simple readily available tools.
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You will need :-- A good quality spirit level, 1 metre long
- A tape measure, in good condition with all numbers readable
- A piece of 4”x2” wood, approximately 7 foot long
- Two pieces of 2” by 1”, approximately 7.5” long
You will need a level surface to stand the car on. If your garage is not level, you can use pieces of hardboard as shown in the picture to the right ( please click for enlarged picture). The hardboard is simply placed on the floor to correct the height difference between the two sides of the garage. Use the spirit level to measure the garage floor before proceeding. Place a spirit level against the wheel, usually resting on the tyre as it touches the floor, this helps for stability. Using the wing for an upper rest, hold the spirit level upright. | |
| Measure from the wheel rim to the spirit level, at the top and bottom of the wheel.
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| | Measure to the flat part just inside the rim, to ensure a good repeatable measurement.
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Distance to top of rim | 23mm | Distance to bottom of rim | 18mm | Difference (top minus bottom)
| 7mm (example) |
The table above shows an example measurement, where the difference between the top and bottom is 7mm. The top of the wheel should be further from the spirit level than the bottom, i.e. negative camber. The specified camber for a Griffith is 0.5 to 0.75 degrees negative (but it is common to run up to 1.5 degrees negative). The angle converts to a measurement using the following formula :- Sin (camber angle) = Measured difference / Wheel diameter For a 15 wheel, the diameter is 400mm, this is the distance between the two measuring points just inside the wheel rim. Thus for 0.5 degree camber :- Sin (0.5 degrees) = Measured difference / 400mmTherefore :- Measured difference = Sin (0.5 degrees) x 400mm = 3.5mmThe measured difference for a 15 inch wheel is 7mm per degree, as an approximation. To set at 0.75 degrees negative camber the measured difference should be 5mm. TRACKINGMeasuring tracking is no more difficult than camber, but does require a ‘special tool’. The tool is constructed from a 7 foot piece of 4x2 timber and two pieces of 2x1. The 2x1’s are screwed and glued to the end of the 4x2 to make a measurement frame. The upright pieces should be half your wheel height, and securely attached so they cannot wobble. The length of the 4x2 is not important, as long as it is greater than the overall track of the car. | |
Place the tracking frame under the front of the wheels, with the 2x1’s nearest the wheel, ensure it is firmly pushed against the front of both tyres. Measure the distance from the inner edge of the upright to the wheel rim, (the same place as previously used for the camber). |
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Measure to the front of the wheels, offside (as shown on the right) and nearside. For consistency, always measure to the same edge of the uprights. Repeat for the rear of the front wheels, slide the tracking frame (laid sideways) under the car, with the 2x1’s uppermost, to avoid accidental damage. Be careful not to catch the uprights on anything, if in doubt remove and recheck. | Measuring to Front of wheels |
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| It is not important where the tracking frame is placed across the car, as long as it is pushed firmly against the tyre | Measuring to rear of Wheels |
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The following table can be used for the results :- | | OFFSIDE | NEARSIDE
| TOTAL
| | FRONT OF WHEEL | 119mm | 107mm
| 226mm
| | REAR OF WHEEL | 134mm | 87mm
| 221mm
| | | | Difference | 5mm
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An example is shown in the table above, indicating that the overall distance to the front of the wheels is 5mm bigger than to the rear, this indicates that the front is further in than the rear, thus toe-ing in. As with camber, the angle can be calculated from the wheel diameter, and the same numbers apply. 5mm of toe-in is equivalent to 5/7 degrees, this is equal to 0.71 degrees or 43 minutes (there are 60 minutes in a degree). The number measured is for both wheels, therefore half for each wheel. This car is set at 21.5 minutes.
The normal setting for a Griffith is between Zero and 20 minutes toe-in (per wheel, which equates to 5mm total). AccuracyThe accuracy of these measurements will depend on how accurate you can read a tape measure, but should be as good as +/-0.5mm per reading. Thus for camber it will be overall +/-1mm. Arguably for tracking it will be as high as +/-2mm, but I have found that I can repeat measurements within 1mm total.
This level of accuracy is perfectly adequate for camber and tracking. Adjustments Adjustments to camber and tracking are nearly as simple as measurements, but do not make any adjustments unless you are fully confident that you are capable and have the right tools. Nic Bowman The author of this document takes no responsibility for how the information contained within is used, or for any consequences thereof.
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