Keith Black Hypereutectic pistons are favored for their improved power and reduced scuffing. The unique design & manufacturing processes combine to produce a rigid piston, which will rock less in the bore improving ring seal. These T-5 heat treated pistons also offer reduced thermal expansion, which allows you to run tighter clearances and allows the piston rings to seal better and minimize blow-by.

390 Hypereutectic alloy
Fully machined crowns and valve reliefs
Drilled oil drain backs
Full floating wrist pins
Triple wound spiral locks
Reflective alloy allows 2% power increase
Quench dome technology minimizes deterioration
Zero deck quench designs
Lightweight wrist pins

For S/B Chevy 383 c.i. (4.000" bore x 3.75" stroke).

Item Details

C/R 58cc=13.8, 64cc=12.6, 76cc=10.9
Piston/Pin Weight: 535 g
Rod Length: 5.7", Ring Style: C

Charts

474-111 Instructions (PDF)

Ring Style Chart (GIF)

Specs

Comp Height 5.7" Rod - 1.433
Comp Height 6.0" Rod - 1.13
Pin Diameter - 0.9272

CA Prop 65

CARB warning

Specifications

KEY SPECS
MFG. Part #	Select Oversize to see
Brand	Keith Black
Piston Style	Dome
Piston Material	Hypereutectic Aluminum

GENERAL
Piston Diameter	Select Oversize to see
Dome Height	Select Oversize to see
Stroke	3.750"
Connecting Rod Length	5.700"
Piston Weight	535 grams
Piston Ring Style	C
Wrist Pin Diameter	0.9272"
Wrist Pin Weight	145 grams
Compression 58cc =	13.8 : 1
Compression 64cc =	12.6 : 1
Compression 76cc =	10.9 : 1
GTIN Code	Select Oversize to see
Sold in Quantity	Set