Big Bore, Sleeved, Aluminum LS Engine Block

Boostline Performance proudly introduces our premium line of aluminum GM engine blocks - precision-engineered for serious performance builders who demand reliability under extreme conditions. Each block starts with a seasoned GM Gen 4 aluminum foundation, then undergoes our proprietary machining process on state-of-the-art Rottler CNC equipment.  These blocks get fully machined for Darton sleeves at our facility using seasoned GM Gen 4 aluminum blocks on our Rottler CNC machine. These sleeves have steps in them to alleviate the possibility of ever "dropping" a sleeve, which could be a problem with straight sleeves. 

Our blocks feature Darton dry sleeves - delivering the crucial performance edge when pushing boundaries with boost or nitrous:

• Superior Tensile Strength: Significantly stronger than factory GM sleeves
• Stepped Design Technology: Engineered to eliminate sleeve "drop" issues common with straight sleeves
• Precision Engineering: Machined to exacting tolerances for optimal performance
• Enhanced Thermal Stability: Maintains cylinder integrity under extreme heat and pressure
• 100% American Made: Uncompromising quality control from materials to manufacturing

Whether you're building a street monster or an all-out competition engine, our flexible sleeve options accommodate bore sizes from 4.00" all the way to 4.185", giving you maximum flexibility for your specific displacement goals.

Features:

• Allows 900+ HP Builds (NA and/or Power Adder)
• Uses Darton Dry Sleeves
• OEM GM Main Caps
• Bore Sizes Available from 4.000” to 4.185”
• All Blocks Are Seasoned and Inspected GM Cores
• Bored To Your Specified Bore Size And Torque Plate Honed
• Zero Decked
• Comes With New Cam Bearings Installed

Please note that if you do decide to supply your block for sleeving and you have had any type of engine failure, there is a chance that your block will not be usable for sleeving. We will to inspect your block once it arrives at our facility to determine if it can be used. We will only be able to resleeve Gen 4 LS and Gen 5 LT aluminum blocks. Gen 3 aluminum blocks cannot be resleeved. We do not recommend larger than a 4.125" bore size for any power-adder use.