Pontiac 400ci Hypereutectic PistonsSolid Dome 10cc4.160" Bore (+.040'')Use w/6.630'' Connecting Rod & 3.750'' Crank StrokeComp. Ratio: 9.4:1/100cc8/pkg Note: Designed to work with 1967 and later 14-degree heads. Piston is .025" below a 10.250" deck. Check small end of rod to piston before assembly / .045" clearance per side minimum.Technical Specs:Alloy: Hypereutectic 390 AlloyBore: 4.160''Crankshaft Stroke: 3.750''Connecting Rod Length: 6.630''Deck Height: 10.250''Compression Height: 1.710''Pin Size: 0.980'' x 3.000''Pin Location: CenteredSolid Dome Top: 10.0cc 2 Valve ReliefsIntake Valve Relief: 0.239" Depth / 2.140" Diameter Exhaust Valve Relief: 0.239" Depth / 2.140" DiameterTop Landing Height: 0.300''Ring Grooves: 5/64'' Top; 5/64'' Middle; 3/16'' Bottom Gram Weight: 582/163Compression Ratio: 9.4:1 w/100cc Combustion Chamber Heads