PRODUCTION-BASED BLOCKS
When building a mild Small-Block performance engine or a replacement for a stock engine, production-based blocks from Chevrolet Performance give you strength, accuracy and peace of mind that can’t be assured in a rebuilt core. And unlike so many of the used cores, nearly all of ours feature four-bolt main caps for extra strength. Each cylinder block is machined to production-spec tolerances and is manufactured to the exact specifications of pre-1986 or 1986-later engines.

Production-Based Block Technical Notes:
• Standard 350 main journal sizes
• Non-siamese bores
• Production-spec cylinder wall thickness
• Lifter valleys machined for hydraulic-roller and flat-tappet valvetrains

350 Bare Block (1986 – Later Style), 1-Piece Rear Main Seal
• Cast-iron 4-bolt block
• 4.000" bore
• Machined for hydraulic roller or flat tappets

 Specs:
•Part Number: 10105123
•Casting Number: 14093638
•Deck Height: 9.025"
•Lifter Pattern: Standard
•Cylinder Wall: Open
•Bore Range: 4.000" - 4.030"
•Main Bolt: 4
•Main Bolt Degree: Straight
•Cap Material: Gray Iron
•Crank Journal Size: 350
•Oiling: Wet
•Seal Type: 1 Piece
•Max Stroke: 3.750"
•Weight (lbs): 181
•Max HP: 350
•Usage: Street