Cyl MID Sleeve GM LS (Set 8) 4.110in ID Bore

The Darton Sleeves Cyl MID Sleeve GM LS (Set of 8) with 4.110-inch ID bore represents the gold standard for serious LS engine builders and high-performance machine shops. These cylinder sleeves are engineered for builders who demand precision overbore capability, enhanced durability, and the ability to refresh tired or damaged blocks without a complete replacement. Whether you're restoring a worn original block or preparing a platform for extreme boost, stroker builds, or endurance racing, these mid-wall sleeves deliver the structural integrity required for forced induction and high-RPM applications.

Darton's MID-wall design positions the sleeve wall thickness optimally between the block deck and pan rails, maximizing cooling jacket efficiency while maintaining superior hoop strength to resist combustion pressures and thermal cycling stress. The 4.110-inch bore specification accommodates aggressive overbore applications beyond stock 4.000-inch limits, allowing displacement increases and larger piston packages essential for turbo and supercharger builds. Each of the eight sleeves features precision-honed finishing and premium ductile iron or steel construction, ensuring consistent bore geometry, minimal taper, and extended ring life under boost and nitrous oxide applications.

LS platform enthusiasts—from bracket racers and street performance builders to serious competitors—rely on Darton sleeves to unlock additional cubic inches and structural reliability when pushing beyond factory tolerances. Installation requires professional machining and honing to achieve proper interference fit and concentricity; TacticalSurplusUSA recommends working with an experienced engine builder or machine shop familiar with LS architecture. This complete set of eight sleeves provides everything needed for a full-block refresh, ensuring uniform bore consistency across all cylinders for optimal ring seal and long-term durability under sustained high-horsepower conditions.