Wiseco PTS533A6 Pro Tru Street Piston Kit Chevy Small Block 350 23° -20cc 4.060 Bore

The Wiseco PTS533A6 is a Pro Tru Street forged piston kit designed for the Chevrolet Small Block 350 with 23-degree cylinder heads, including marine 6.2L applications. This reverse-dome (dish) piston kit is built to deliver reliable performance at a competitive price point, making it an ideal choice for stock rebuilds, street builds, and marine engine restorations.

Wiseco's Pro Tru Street series pistons are forged from 4032 alloy aluminum in Mentor, Ohio, offering superior strength and durability over cast alternatives. Each piston features an ArmorGlide skirt coating for seizure resistance, reduced friction, and quieter operation—critical for the sustained high-load demands of marine environments.

Key Specifications:

• Bore: 4.060 in.
• Compression Height: 1.425 in.
• Stroke: 3.750 in.
• Rod Length: 5.700 in.
• Dish Volume: -20cc
• Compression Ratio: 9.4:1 (64cc chamber) / 9.2:1 (67cc chamber)
• Pin Diameter: 0.927 in.
• Displacement: 388 ci
• Replacement Piston P/N: 5533A6
• Ringset Included: S100S8-4060-5

Kit Includes:

• Plasma moly piston rings
• Chromium alloy steel wrist pins
• Spirolox retaining clips

The PTS533A6 is specifically suited for Chevy Small Block 350 builds using 23-degree cylinder heads, with compatibility noted for 6.2L marine (build-to-stock) configurations. This kit provides everything needed for a complete piston assembly, simplifying the rebuild process for both professional engine builders and experienced DIYers.