Piston Set by JE - 77.25mm +.25mm Oversize Bore | 8.3:1 CR | Stroke 85.8mm - MINI Cooper S 2002-2008 | 312424

NOTE: Image shown not actual parts.


JE Pistons is the leader in forged racing pistons. With 70-plus years of experience, in-house forging, and industry-leading technology, JE Pistons are designed to perform at the top levels of all forms of motorsports.


Bore (in) 3.041
Bore (mm) 77.249
Top Compression Ring Thickness 0.0480
Second Compression Ring Thickness 0.0480
Oil Ring Thickness 0.141
Forging Type Round
Volume (cc) -1.00
Series JE Pistons
Piston Head Type Inv Dome/Dish
Pin Diameter (IN) 0.827
Compression Height 1.043
Make MINI
Wrist Pin Style - floating or press fit Floating
Wall Type CHAMFERED
Wall Thickness (IN) 0.150
Ringset Part Number JG0004-3051
Ring Brand ProSeal
Ringset Included Yes
Retainer Thickness 0.063
Retainer Lock Style Wire Lock
Retainer Lock Part Number 827-063-MW
Retainer Diameter (IN) 0.827
Replacement Single Piston 312424S
Piston Pin Inside Diameter 0.527
Piston Pin Material 5115 LOW CARBON STEEL, CASE HARDENED
Piston Material 2618
Piston Pin Length (IN) 2.250
Piston Avg Wt 241
Pin Offset No
Pin Brand JE Pistons
Pin Part Number 827-2250-15-51C
Pin Included Yes
Pin Diameter (mm) 21.00
Oil Rail Support Part Number (If Required) 3040-122
Oil Rail Support Included Yes
Oil Rail Radial Wall 0.122
Deck Clearance -0.110
Brand JE Pistons


OE Part # for standard sized piston:

11-25-7-520-131 / 11 25 7 520 131 / 11257520131

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