Running a very low, dynamically-loaded chassis requires precise spring and damping rates. However, the Traxxas chassis is optimized for off-road use with provisions for very long-travel suspension. Unfortunately this bias is exactly the opposite from what would be ideal for road use. In stock configuration, the front wheel rate to shock rate ratio is nearly 2:1, allowing a compact shock to take up a very long-travel load from the wheel.

Our road car is using about a quarter of the available travel, which in turn utilizes a minuscule amount of the available shock travel. The problem this creates is that spring rate has to be very stiff to control the input leverage, and the damper has to be stiff to control the spring... all of which negatively impacts the suspension's capacity to stabilize the car on pavement.

Moving the pushrod pickup point closer to the rocker's center by 3/16 of an inch nets a 50% increase in wheel travel rate. After this mod, the ratio is improved to 1.4:1 and is able to engage nearly all of the shock's damping travel. We can run a dramatically softer spring (since we're spreading the same load force over a longer distance) and thereby allow for a much more responsive and supple suspension. (Incidentally, this rate is nearly identical to the standard rear-rocker's rate so grab a rear set of those custom modular rocker plates)