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16mm Pro-Built 5 Hole Fat Boys [2.7mm] Piston Set

16mm Pro-Built 5 Hole Fat Boys [2.7mm] Piston Set

Product Code:SCH1506
Price: $20.00
Qty:     - OR -   Add to Wish List Add to Compare

**Jan 2024: This RC8B4.1 package includes 4 pistons, the rear bevel pistons are pre-drilled (3x1.5, 2x1.7), Fronts flats are drilled (4x1.4, 1x1.5) unless otherwise requested.**

The Schelle Fat Boys piston lineup is built around the concept that a thicker piston will limit flow around the outside forcing oil through the valving holes.  For smooth and hot weather conditions, the 2.7mm versions are ultra thick, so the valving path is only 2.7mm tall, adding pack for hot weather and high grip.  Keeping the outside height 2.7mm makes the car that the suspension won't flutter, and can pack properly without using extremely thick oils.   The ultimate high grip and hot weather weapons, these are made to make the shock more consistent by using a thinner oil and creating more drag via the extended height.   The bottom side of the piston is pocketed to fit standard shock shafts.

*for lower grip you may want to drill a 2nd larger 1.6mm hole in the rear pistons.

Hot Weather (emulsion):
Front: 40 wt AE 4x1.4 & 1 x 1.5mm
Rear: 32.5 wt AE   3 x 1.5 & 2 x 1.7mm  (for 3rd hole rear arm, use 35 for middle arm hole)

Cold Weather (below 70F):
Front: 37.5wt AE  4x1.4 & 1 x 1.5
Rear: 30 wt AE  3 x 1.5 & 2 x 1.7mm (for 3rd hole rear arm, use 32.5 for middle arm hole)


  1. Precision CNC Routed Delrin (TM) pistons, sold in Pro-Built set of 4.
  2. Hand marked on the top side with valving size
  3. Bevel edge rear for faster rebound.
  4. Reduced clearance and 2.7mm Fat Boy thickness for less blow-by on landings, the result is less "flutter" in the suspension.
  5. Fits electric and nitro Associated RC8B4 and RC8T4 (and older versions) and Mugen MBX8 and MBX8T series, XRAY XB9 buggy series.


"I used the pistons today at the track with your recommended oils and my car was about 1/2 second faster around the track. The car was more plush with more traction. Thanks for the awesome product."    -Tim F.   (MakinTraxx RC, New York)   Conditions:  Track was dry and bumpy with a loamy outside.