MRX-5 Rear Upright 7075-T6 Upgrade - MUGEN AM-MRX5-H2124 by Arrowmax  [AM-MRX5-H2124]

How the rear upright affects suspension feel

This Arrowmax rear upright is a scale replacement machined from 7075-T6 aluminium made for MUGEN MRX-5 platforms. The precision-machined uprights come with two sets of composite rings that sit against the pivot ball, sharpening suspension sensitivity and smoothing articulation through both compression and rebound.

Fitted as a direct swap for the stock plastic uprights, the aluminium parts alter chassis behaviour: they tend to increase on-power understeer slightly at corner exit compared with softer stock components. Knowing this helps when you adjust toe, anti-roll characteristics, or shock valving to recover rear traction.

Installation uses the standard wheel hub removal and pivot ball retention hardware and requires no extra modifications for MRX-5 fitment. When refining setup, change pivot compliance incrementally using the supplied composite rings rather than making large adjustments to shocks or anti-roll bars.

For MRX-5 racers wanting a tougher metal upright and a more tactile pivot-ball feel, this Arrowmax AM-MRX5-H2124 delivers measurable improvements in suspension response and a predictable shift in rear traction under power.