Wheels: Track Width and Spacing and its Effect on Handling

This blog post is the second in a two-part series on wheels. In this post, we explain tracking/spacing, and the effects on handling.

What is wheel spacing/tracking?

Wheel spacing (or tracking) is a very effective chassis tuning tool. Spacing is the process of moving the wheel in or out in relation to the centreline of the race car.

Front End Spacing

Generally, the front spacing is left alone as it is not really adjustable as there are no spacers on the axle. You must change the whole axle width. Only sometimes, when the handling really needs some help, the right front wheel offset is changed, and this pushes the front wheel either towards or away from the chassis.

Which axle size should I use and why? Generally, a winged sprintcar uses a 50" axle, and a non-wing a 52" or 53". Wider trackwidth with a 53" for a non-winged racecar at the front end will help keep the car from tripping over the right front and will help keep the left rear from lifting off the ground. You do not need this width on a winged car as they are buried over on the left rear due to the wing and trying to pull the right front off the ground, so the closer it is to the chassis, the less likely it is to unload.

Rear End Spacing

The rear-end spacing is what is adjusted the most on a sprintcar. The rear wheels can easily be moved with axle spacers. This then changes how the racecar will track. A tip to remember is the right rear turns your racecar, and the left rear drives you.

We have, in our opinion, one of the best spacer kits on the market. It allows you to move the wheel in or out without having to keep additional spacers. Once the spacing is correct, move the existing spacers from the inside to the outside of the wheel centre. View our kit by clicking here

Right Rear Spacing

The right rear is the most important tyre to adjust with spacing. Widening or narrowing the rear track width of the car by moving the right rear in or out changes weight loading on the right rear tyre during cornering, and also adjusts the arc of your turn (see diagram below). If you space the right rear out further, it travels a wider arc, which makes the car turn easier.

Also, moving the right rear wheel outward from the chassis centerline decreases weight loading, while moving it inward closer to the chassis increases weight loading during cornering.

Rule of Thumb

Moving the right rear out frees up the chassis when the track is rough and sticky. Moving the right rear in when the track gets slick tightens up the car.

Left Rear Spacing

Spacing is used at the left rear as well. In most cases, the left rear wheel is positioned as close to the chassis as possible without rubbing on the suspension. But if the track gets slick or has long momentum-type corners, then the left rear wheel can be moved away from the chassis to increase the weight percentage on the right rear. This will stick the car better at the corner entry and increase the right rear side bite. It will increase forward traction at the right rear as well.

What should I place my right rear wheel spacing at?

In general, the centreline of the right front tire is set in line with the centreline of the right rear tire patch as a starting alignment. However, this is part of an overall setup, so one recommendation is hard to suggest as there are so many other factors. What we do suggest is first try what your chassis manufacturer recommends and then adjust based on your desired preference and how you would like the car to feel.

How do I measure my rear spacing?

Generally, to measure your spacing, you measure the distance from the frame upright on the chassis to the centre of the rear tyre (see image below).

It's crucial to emphasise that changing the tracking/spacing of your wheels represents only a single element within sprintcar setup. Teams also take into account various other factors like suspension configurations, tyre pressures, wing adjustments, and additional aspects to enhance the car's performance according to distinct tracks and racing conditions.