Repl Cyl Sleeve Dart SBC 4.115 Bore 4300 OD

The Repl Cyl Sleeve Dart SBC 4.115 Bore 4300 OD by Darton Sleeves is a precision-engineered cylinder sleeve designed for small-block Chevrolet engine builders seeking to restore or upgrade bore diameter capabilities. This replacement sleeve allows engine rebuilders to reclaim oversized or worn cylinder walls by sleeving the block back to a standard 4.115-inch bore specification. Whether you're restoring a classic performance engine, repairing cylinder damage, or preparing a block for stroker or boosted applications, this Darton sleeve delivers the dimensional accuracy and material quality that serious mechanics demand.

Darton Sleeves manufactures cylinder sleeves using premium cast iron or ductile iron construction, depending on application requirements, ensuring excellent heat transfer and minimal distortion during thermal cycling. The 4300 outer diameter (OD) specification provides the proper interference fit for SBC block architecture, while the 4.115-inch bore diameter maintains compatibility with standard small-block piston and ring packages. Precision honing and straightness tolerances ensure repeatable bore geometry, critical for ring seal, oil control, and long-term cylinder wall durability in both naturally aspirated and forced-induction builds.

This sleeve suits engine builders restoring Chevrolet small-block platforms—283, 305, 327, 350, 400—where original bores have worn to +.030 or larger or sustained localized damage. Installation requires professional boring and honing equipment to achieve proper interference fit and final bore sizing; most machine shops will press-fit the sleeve and finish-hone to final specification. Pair this component with quality piston and ring sets to maximize compression and ring seal performance for street, competition, or high-horsepower applications.