Hasting 139

Hastings 139 is a piston ring set for 4.000” / 101.60 mm bore. The set is intended for engines using 5/64–5/64–3/16 ring grooves, so selection should be based on piston and cylinder dimensions rather than vehicle make alone.

Application / fitment

The rings are used in many classic American engines with a 4.000” / 101.60 mm bore when the piston has matching ring groove widths. This bore size appears in popular Small Block and selected other V8 configurations, but cylinder measurement, piston design and ring type determine final compatibility.

• bore: 4.000” / 101.60 mm
• top ring groove: 5/64”
• second ring groove: 5/64”
• oil ring groove: 3/16”
• V8 engine set — 8 cylinder sets

Before installation, check cylinder bore, taper, out-of-round, ring end gap, ring side clearance in the piston groove and cylinder finish. The number without an oversize suffix indicates STD size; oversize versions should be selected according to the actual cylinder size after machining.

Technical information

• Part type: piston rings
• Bore: 4.000” / 101.60 mm
• Ring layout: 5/64–5/64–3/16
• Size: STD
• Number of cylinders: 8
• Selection: by bore size, piston grooves and required ring end gap