Higher Downforce Tuning Theory

With higher downforce vehicles, there are more ways you can exploit the physics to find speed. The first one to abide by is to maximise vehicle response. This is on the basis of the tyres have more grip and less slip angle, more about this has been discussed in Tyres Overview.

For majority of higher downforce vehicles, there are 2 specific base setups that are near universal across all Gr. groups apart from Gr.B. The setups are to maximise corning speeds and to maximise top speeds. The only real big alterations you may make from track to track will probably be differential, natural frequency and downforce settings. All other settings are fairly universal when comparing setups from track to track.

With higher downforce vehicles, you can start to incorporate the elements of a top speed setup within the base setup. For instance, downforce is generated at the square of speed. This means that the faster you go, the downforce generated increases exponentially. With this knowledge we can further increase our setup potential.

The higher the Downforce Lv created, the even more crucial aero efficiency will become. This is where the tuning of Gr. and Super Formula differ to road vehicles. In all cases for Gr. and Super Formula, the easiest way of increasing aero efficiency is to use minimum body height.  This may force you to drive a little more refined as it will result in a more nimble car. Unless you are experiencing lots of handling imbalances in either oversteer, understeer or erratic bottoming out resulting in crashes, there will be no benefit to raising the vehicle's body height. Resulting in so will greatly decrease it's aero efficiency. Raising the car by even 1mm will increase drag and reduce overall downforce.

In most cases for Gr.4 and Gr.3, maximum downforce is usually the best starting point. This is because the benefit of more downforce in medium to high speed turns and a higher braking force potential, can greatly out weigh the ~2 mph decease you may experience on the longest straight. For Gr.2, Gr.1 and Super Formula you can start to utilise the effect as shown above, more than Gr.4 and Gr.3 in comparison. This is because natural frequency ranges are quite low and the maximum downforce ranges are quite high. Both of these reasons is why more fine tuning is needed when adjusting natural frequency and downforce settings.

As previously commented on Natural Frequency, you will normally want higher rear frequency than front frequency, this will be even more relevant to higher downforce vehicles. As speed increases, the more downforce will be produced, compressing the vehicle into the ground. As the rear wing can produce more downforce compared to the front, the rear ride height has a higher potential to decrease when at speed.

When at speed, if the rear natural frequency is not high enough you will experience high amounts of understeer during high speed turning. This is because the rear ride height will be lower under the compression of rear downforce.