Description:

GM's aluminum LT production block has proven itself to be a strong performer.  We see this block as being able to reliably handle over 1,000 hp.  That could not be said about its aluminum LS predecessor. 

This LT4 short block benefits from our state-of-the-art CNC machining which  provides a level of precision far beyond OE (see video below). All blocks are individually serialized on our 4-axis CNC for traceability. We install premium Dura-Bond cam bearings and replace the OE main bolts with P1 main studs.

The P1 studs are a major upgrade over the OE main bolts of unknown origin.  P1 manufactures all these studs from E190 steel alloy in their new Rogersville Missouri plant. The torque on a stud is all applied in a single direction whereas a bolt also twists.  Studs are not therefore susceptible to "unwinding" and provide greater clamping force.

The Callies Compstar crank we use is fully counterweighted. Having eight counterweights instead of six increases rigidity and reduces harmonics.  The net result is far less flexing of the crank which greatly enhances longevity. The forged Compstar Extreme I-beam rods with ARP rod fasteners are also a big jump up from the OE powdered metal rods. Another big jump up comes with the forged Diamond pistons. These have a 9cc dish and are intended to run either naturally aspirated or with light boost.

Part selection far from the whole story. Our all CNC shop and highly trained staff will machine the parts to perfection on our state-of the-art equipment. The rotating assembly is computer balanced to tight tolerances. The block is decked and milled on our 4-axis CNC followed by align honing of the mains. The last machining step is CNC cylinder honing where we achieve the exact surface finish for the ring package and achieve a bore diameter precise to 0.0001 inch.  Check out the honing video below to see exactly how this is done. 

We offer four variants of this short block as follows:

• Stock stroke for 376 cubic inches (revs faster and higher)
• 4.000 inch stroke for 417 cubic inches (more peak horsepower)
• Wet sump compatible crank snout
• Dry sump compatible crank snout

These short blocks are quick ship items.  We normally have them either on the floor fully assembled and ready to ship or machined and ready to assemble. Call us at 815-725-2727 with any questions or to place your order.

Shop Video

CNC Honing Video

Block Machining