Nelson Engineered Performance LLC

Dominant Inputs: The Pillars of Chassis Setup.

The first step in creating quality setups and adjustment plans is knowing which inputs on your car are dominant. There are an almost endless number of inputs/changes that can be made on your race car. Dominant inputs are the inputs and adjustments that overpower everything else. At Nelson Engineered Performance, our main focus revolves primarily around the dominant inputs listed below. We do not claim this to be the only way to approach chassis setup, it is simply the approach that works best for us and our customers.

While we certainly look at the following inputs in a static state and use static measurements as reference points, it is studying them in a dynamic state that provides the most value to race teams. Our pull-down service allows teams to do just that! Observing how your car’s balance, wheel positions, and platform change while under race load will change the way you approach your car’s setup and race strategy.

Additionally, there are a ton of adjustments available to manipulate and optimize these inputs. Bar changes, air pressure changes, moving ballast, birdcage adjustments, and spring load changes are just a few of the changes that can impact your dominant inputs. It isn’t always the adjustment that’s important, it’s the impact on your dominant inputs that’s important. For example, the driver doesn’t feel the bar angles of the car, what they feel is the impact the bar angles have on the dynamic bite within the car. Our pull-down rig service will allow you to view the dominant inputs within your car’s setup. From there, we can use software to help adjust any inputs that might be out of range.

Dominant Balance Inputs

Dynamic Cross %

Dynamic Front/Rear %

Dynamic Left/Right %

Dynamic Bite

Dominant Wheel Position Inputs

Dynamic Rear Steer

Dynamic Toe

Dynamic Camber

Dynamic Platform

Platform is the final dominant input. It’s the overall pitch and roll of the chassis and is the glue that holds the setup together. Platform is primarily adjusted through spring setups and load changes. Once we have your balance and wheel positions set at a platform we like, your main goal is to simply maintain that platform throughout the night. As lap times slow down throughout the night, teams need to be able to anticipate how their platform might change and determine the proper adjustment(s) to bring it back within range. With our pull-down and spring setup services, we can view how your dynamic platform and simulate the impact of changing track conditions. By putting in work on the pull-down beforehand, teams will know what adjustments to make before they even head to the track.