Toe alignment using straight edges

A simple method for checking front and rear toe alignment

To enjoy the benefit of a Lotus' suspension and its cornering ability it is important that the wheels actually point in the direction that Lotus intended.

The "string method" for checking toe settings is well known and described in this forum.

However I have found that using straight edges can be a little easier to set up and handle if you add a few easy measurements and calculations.

What you will need are these simple tools:

 1. Two 4 meter long builders straight edges

 2. Four 5 liter sprinkler fluid bottles

And the setup is simple too, like this:

The sprinkler bottles are placed up against each wheel. The straight edges are placed lying down on top of the sprinkler bottles and the straight edges touches the sidewall of the tyres. The ends of the straight edges should overhang the front and the rear of the car.

Common 5 liter sprinkler fluid bottles are ideal as they are suitably heavy when filled with fluid, they are level on top and their height conveniently matches the center height of the wheels.

Any material for the straight edges can be used as long as they are straight and don’t bend. It is easy to check edges against one another; turn them round and recheck, they should not show any gaps or twists. Builders straight edges can be bought from builder’s material markets and there are lots to pick from on the internet. I used SVALK aluminum extrusions of 18 x 100 mm, but any sensible straight and stiff ones will do.

Placed against the tyre sidewalls the straight edges are not parallel and do actually toe-in a little. So we will have to quantify the amount of toe-in of the straight edges which of course will be our references.

The distance between the straight edges front and rear is measured as well as the length of the straight edges. From the drawing below you can see the measurements obtained from a car with standard rims and standard tyre dimensions.