Kyosho IF347-138 Big Shock Piston 1.3x8 Hole

Shock pistons for Kyosho's Big Bore dampers, drilled with eight holes of 1.3mm diameter, supplied two to a pack.

The piston is the disc that moves through the oil inside the shock body, and the combined open area of its holes determines how fast that oil can pass. That flow rate is what damping actually is. More holes at a larger diameter means freer flow and faster, softer damping; fewer or smaller holes restrict it and slow the suspension down.

Eight holes at 1.3mm is the most open combination in Kyosho's IF347 range, giving the largest total flow area of the group. That makes it the choice for rough, rutted and bumpy tracks where you want the suspension moving freely and absorbing square edges rather than packing down over successive hits. It is typically run with heavier oil, since an open piston with thick fluid often gives better big-hit control than a restrictive piston with light oil.

Kyosho positions these as setup parts to change with track and seasonal conditions. Fitment covers the Inferno MP10, MP10 TKI3, MP10T, MP10e, MP9 TKI4 V2 and Inferno NEO 3.0 and 4.0 VE.