KB Performance Hypereutectic Piston Set

Fits: Mopar Big Block B

Eng. Disp. In. 400

Eng. Disp Liters 6.6

Year Range 1971-1978

Bore (in) 4.342

Bore (mm) 110.3

Stroke (in) 3.38

Stroke (mm) 85.9

Oversized Yes

Ring Pack 5/64, 5/64, 3/16

Top Land .275

Pin Number 1.094x300KA

Pin Type Press or Floating

Pin Diameter (in) 1.094

Pin Diameter (mm) 27.8

Lock PRF116-3

Compression Height IN 1.908

Compression Height MM 48.5

Crown (cc) +8cc

Alloy 390

Compression Ratio 72-10.3, 80-9.5, 84-9.2, 88-8.9

KB Performance hypereutectic pistons are made from 390 aluminum alloy and heat-treated to T6 standards, which makes them 30 percent stronger than ordinary untreated hypereutectics. Their 100 percent CNC-machined crowns, high upper compression-ring location, gas-accumulator groove, drilled oil returns, and spiral-lock retainer grooves make these pistons outstanding for performance applications. They have a lightweight, rigid-rib skirt design that stabilizes the piston in the bore. All of this adds up to pistons that fit tighter than forged types, provide improved oil control, reduce blow-by, increase ring life, eliminate cold start-up knocking, and won't cost you an arm and a leg! Thousands of models are available—find the set and options designed for your vehicle and engine application.