M AXIMUM E FFORT™ R ACE P ISTONS
All HRC pistons are machined on the most modern CNC equipment in the industry. They are forged from 2618-T61 aluminum for ultimate strength and fatigue resistance. The design of the CNC turned skirts allows these pistons to work properly under intense heat and severe side loads without scuffing or splitting the cylinder walls. Skirt to wall clearance on most HRC pistons is designed to operate at .004” clearance. Dome pistons are designed with radiused domes, eliminating sharp edges and “hot spots”. The valve pockets are built to handle large cam profiles and oversized valves. Pocket angles are designed to work with most angle-milled heads. Forced pin oiliers are standard, as are the aircraft quality pins that are heat-treated and end ground to work in floated or press fit applications. Double spiro lox are included. Replacements are available as needed. Rings are available for all stocking pistons.

Application	Part Number	Bore Size	Stroke	Rod Length	Dome Volume	Comp. Ratio w/64cc chambers	Comp. Distance	Average Weight
SBC 350	HOW HRC4557	4.000	3.480	6.000	-4.0cc FT	10.7	1.268	389
SBC 355	HOW HRC4572	4.030	3.480	6.000	12.7cc DOME	13.6	1.268	455
SBC 355	HOW HRC4579	4.030	3.480	6.125	-4.0cc FT	10.6	1.133	382
SBC 357	HOW HRC4585	4.040	3.480	6.000	12.4cc DOME	13.6	1.268	466
SBC 383	HOW HRC4584*	4.030	3.750	6.000	7.8cc DOME	13.1	1.133	485
SBC 377	HOW HRC4569	4.155	3.480	6.250	-6.0cc FT	10.6	1.000	371
SBC 400	HOW HRC4566*	4.155	3.750	6.000	-4.0cc FT	11.8	1.133	402
SBC 400	HOW HRC4561*	4.155	3.750	6.000	6.7cc DOME	13.6	1.133	433
SBC 400	HOW HRC4582*	4.155	3.750	6.000	6.7cc DOME	13.1	1.120	433
SBC 420	HOW HRC4568	4.155	3.875	6.000	-4.0cc FT	11.9	1.063	379
SBC 420	HOW HRC4581	4.155	3.875	6.000	1cc DOME	13.0	10.71	406
SBC 434	HOW HRC4562	4.155	4.000	6.000	5.6cc DOME	13.9	1.000	411
SBC 434	HOW HRC4580	4.155	4.000	6.000	1cc DOME	13.4	1.008	395

*1/16, 1/16, 1/8 Ring Grooves