2JR QR25DE Sleeved Block B15/B16

Finally! 2JR QR25 Blocks with Darton MID Sleeves, installed. The stock block tends to crack the liner after 400whp. These blocks are good to over 700whp while the Darton MID Sleeves are made of ductile iron and are able to hold over 1000hp. The sleeves are unfinished and will need to be honed to match your piston size.

Benefits:
Cast iron performance in an aluminum block
Improved block integral strength
Improved cooling

NOTE: WHEN CHECKING OUT, SELECT FREE SHIPPING - SINCE YOU ALREADY CHOSE A SHIPPING OPTION ON THIS PAGE.
YOU WILL RECEIVE A $250 CORE CHARGE WHEN A GOOD USABLE BLOCK IS RETURNED TO 2JR, THAT MEANS NO HOLES, ETC.

Sleeving Process:
includes the removal of the old sleeves, machining the block for the new sleeves, installation, and step decking. The process is done on a 3-axis CNC machine. Next the block is honed using a torque plate to simulates the QR cylinder head being bolted on and ensure the cylinder is as true as it was while in the honing machine. The QR is then line bored (where the crank sits) and honed to ensure its perfect.

Each block is:

- Hot tank cleaning
- Darton MID Sleeves Installed
- Bore & Hone w/ Torque Plate
- Line Bore