These Darton "DRY" sleeves are designed to replace your factory cylinder liners with a stronger, more durable, and longer lasting ductile iron surface that can hold more power, and be bored further than stock. Many engine blocks cannot take excessive boring, or high boost circumstances without failing. Switching to a Darton Dry sleeve will solve this problem.----------------------- These sleeves are designed to be pressed into your block, providing a strengthened ductile iron cylinder wall surface preventing cracked cylinder walls at higher power. Upgrading to Darton Dry Sleeves is a good idea for anyone who either needs to bore more than 1mm over on their factory cylinder wall to get a smooth finish, or is looking to hold more power than they are comfortable trusting the factory sleeves with. As a general rule of thumb with these sleeves, we recommend that you not bore any more than 1mm over standard. ----------------------- DRY SLEEVE, means that the sleeve does not contain water/coolant passges bored through the top flange. This solid design provides a more rigid structure to prevent warping and sleeve expansion. ALL Darton Sleeves come from the factory slightly smaller than stock bore. ALL Darton sleeves must be finish bored and honed to the specs of the pistons going into them. You CAN NOT install a piston into ANY Darton sleeve the way it arrives from the factory. This ensures that you will get the exact proper piston-wall clearance to provide a tight seal in your engine. Your machine shop already knows this, and now so do you. Dry sleeves are named so because the sleeve body is not exposed to any cooling liquid within the block and is always installed in a block with an interference fit. ----------------------- Darton manufactures ductile iron sleeves for dry installation in aluminum blocks with special surface finishes and recommends that aluminum block cylinder walls be lightly honed with "Brush Research" bumble hones prior to sleeve installation. The combination of male and female surface preparation greatly enhances heat transfer when the sleeves are installed and fit properly. Bore: 4.110 O.D.: 4.325 O.D. 2: 4.314 Wall: 0.108 Length: 5.800 Flange Thickness: 0.215 Flange Diameter: 4.575 Flats: 4.398 Application: LS2 LS3 LS4 LS7 4.125 BORE