Setup Rationalization for High Downforce Cars (SFL)

Setup Rationalization for High Downforce Cars (SFL)

Optimizing setups for best lap times or "best/safe" racing is both an art and a science. There are many variables and the potential combinations are almost infinite.  So having a "rationale" and an "informed starting point" is important.

The Super Formula Light (Dallara 324) is a near perfect example of a high downforce car. This relatively high downforce makes an understanding of mechanical grip as well as aero downforce important.

While it is possible to use the iRacing setups as a starting point, I discovered that a much better way was to subscribe to RRSetups (RidgwayRacing). Robert provides a highly developed setup for each track. He accomplishes his optimization thru a series of intense testing iterations and telemetry analysis. For most, his setup is optimum, but for some, some modifications are helpful--sort of like tailoring a suit for a perfect or just more comfortable fit. To help in this area of learning, I engaged Scott Haddock (CoachHaddock) to run a bunch of laps together in a two hour coaching session at Imola.

Through a trial and error process of testing at Road Atlanta, Interlagos, VIR and Watkins Glen, along with a close examination of Ridgeway setups and testing with Haddock at Imola, I developed a setup that worked quite well for me. I am 75 years old with a physical handicap due to having two broken legs in an airplane crash.  I seem unable to take full advantage of the maximum cornering speed the SFL is capable of, so my "tailoring" was to reduce aero drag and downforce in exchange for higher straight line speed. I tested this in a race at Watkins Glen and called this starting point my "Base" setup. 

This "Base " setup worked satisfactorily at Imola, but I was sure I needed some setups with higher downforce-for Hungaroring as an example. 

My approach was straightforward. The "Base" setup provided what I found to be the optimum level of "mechanical" grip so my settings for springs and dampers remained almost unchanged. My changes focused on aero drag and downforce with attention to any needed ride height adjustments due to higher downforce. 

The aero options of the SFL are sophisticated and advanced: The "Aero Package" of High or Medium Downforce configuration; Front wing/flap angle; Front flap gurney; Rear wing/flap angle; and Rear beam wing of the undercar diffuser. iRacing provides an "Aero Calculator" which is useful to a point, but it requires telemetry data to determine the front and rear ride height at speed. 

The two most obvious data points provided by the calculator is "Downforce to Drag" and "Aero Balance".   Thru experimentation I determined that my best performance on most tracks called for an Aero balance around 43.5% - 44% for dry tracks and 40.1% for a wet track. This % is the percentage of total downforce on the front tires. A 43.5% Aero balance provides 56.5% of the downforce to the rear tires. 

To verify the accuracy of my "feel" during testing, an examination of tire wear and temps confirms the Aero balance and general setup is close to ideal. The figure above indicates tire temps confirming a slight understeery balance