If you are looking for the official game client itself, the LFS Patch Z28 was a significant update that introduced:

The fluorescent hum of the internet café was the only sound Alex needed on a Tuesday night. It was 2008, the golden age of simulated racing, and for Alex, there was only one king: Live for Speed. But he didn’t want the stock experience. He didn’t want the careful, gradual progression of the GTi or the predictable slide of the XRT.

LFS 0.5z28 Tweak is a community-created modification for Live for Speed (LFS), the lightweight, physics-focused online racing sim. It bundles a set of carefully chosen tweaks and enhancements intended to refine vehicle behavior, visuals, and usability while keeping LFS’s core lightweight, simulator-first philosophy intact.

: Change cars from Front-Wheel Drive (FWD) to Rear-Wheel Drive (RWD) or All-Wheel Drive (AWD). Suspension & Braking

Modify spring rates and damping beyond factory limits for drift or drag builds. Weight Distribution: Shift the center of gravity or overall mass of the vehicle. Wheelbase & Track Width: