8th ‘XV4′ 15.85mm Pistons for AE, Tekno, Sworkz

This is a pair (2) of patented VRP ‘XV4’ Pistons. Each set includes the Transition Valves (not installed). The rebound booster hole is precision-drilled to the exact size proven through extensive testing to deliver the best all-around performance. Whether you're driving on rough, blown-out outdoor tracks or smooth, high-grip indoor clay, the VRP Piston provides a noticeable advantage and more consistent handling.

Simple, Effective Performance

The XV4 Pistons are designed to increase rebound only. Compression remains the same as a standard 8-hole 1.2 piston, meaning no major setup changes or complicated tuning. Drivers consistently report immediate improvements the moment they pull the trigger—more stability, more grip, and more confidence.

You’ll feel the difference right away, thanks to the piston’s design that channels oil through the holes rather than around the perimeter. We recommend starting with your normal shock oil, since only the rebound characteristic changes.

Washer Installation Requirements

The VRP ‘XV4’ Pistons must be run with a washer above and below the piston.
Every set includes a Washer Hardware Pack to ensure proper installation.

Color-Coded Rebound Washers Included

Each piston set includes four upper washers, each providing a different rebound rate:

• Black – Most rebound

• Red – Slightly less rebound

• Gold – Moderate rebound

• Blue – Least rebound

Tuning guidance:

• Use more rebound (Black) on loose, low-grip, or blown-out tracks with large ruts.

• Use less rebound (Blue/Gold) on smooth or high-traction surfaces.

• Recommended baseline: Black washer in the rear pistons, Red washer in the front pistons.