TRF421X Upper Arm Mount A 3451580 - Setup Replacement by Tamiya  [3451580]

Arm Mount A: Baseline Geometry for TRF421X

Item 3451580 serves as the replacement upper arm mount A for the 42391 TRF421X assembly. It forms the fixed connection for the upper suspension arm on the TRF421X and is intended as a direct service part for setup restoration.

Fit and function: the mount reinstates the intended factory geometry so suspension kinematics stay consistent. Confirm correct orientation and tighten fasteners to the TRF421X recommended specs during fitting to avoid binding or excess movement.

Tuning role: fitting a new mount reestablishes the baseline arm position, allowing tuning changes—camber tweaks, roll center shims, and arm length adjustments—to be applied from a consistent starting point.