In Stock Ready to Ship
GM Gen 5 LT1 & LT4 resleeved aluminum block. Sleeved right here at Mast Motorsports in our state of the art Haas VF4 CNC machine.
Mast Motorsports only uses premium USA made Darton Dry Sleeves. Darton sleeves are used in all premium high end forms of racing - NO compromises.
Blocks are machined with a step to mate with the Darton sleeve to maximize seating, and eliminate sleeve shifting. Sleeves are pressed in with loctite and aircraft sealer to maximize the mechanical bond of the sleeves.
Our manufacturing team vibratory stress relieves all blocks to ensure all negative residual stress is removed from the sleeving process.
All Blocks come STANDARD with Block Machining & "Blue Printing"- Line Hone, Decking, Rough Bore, Vibratory Stress Relief.
- Decked to 9.230"
- Standard (min) Sleeve Bore is 4.110"
- Max Bore Size Naturally Aspirated 4.187" Diameter
- Max Bore Size Boosted 4.130" Diameter
Choose your Options:
- Base Level Sleeved Block - ready for bore & hone - comes with 4.110 Rough Bore
- ARP Main Studs
- Final Bore & Hone to Your Supplied Spec
- Final Bore & Hone to match your pistons