Description:
GM's LT iron (L8T) and aluminum (LT4) blocks have proven to be strong performers. We have found these blocks able to reliably handle far more power than their LS predecessors.
These short blocks benefit from our state-of-the-art CNC machining which provides a level of precision far beyond OE. 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.
LT4 Aluminum Short Blocks
The Callies Compstar cranks we use are forged and 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. These cranks are available for both wet and dry sump applications in both stock and 4.000” stroke lengths yielding 366 and 416 cubic inches respectively. 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 Competition Series pistons. These have a 9cc dish and are intended to run either naturally aspirated or up to about 10 pounds boost. Want more boost and a cast aluminum block? We can upgrade you to a 6-bolt, HIP-treated LTR block with the high-boost internals of the L8T.
L8T Iron Short Blocks
The forged factory L8T crank has 8 counterweights and is budget friendly relative to aftermarket. Its 3.858” stroke with a 4.070” bore yields 402 cubic inches. The L8T crank is only available in a wet sump design. We switch to a 4.000” stroke Callies Apex cranks for dry sumps. The Apex cranks (wet or dry sump) are recommended for boost over 15 psi. Our L8T short block is equipped with Callies Ultra-Enforcer I-beam rods and Diamond LT2K pistons which are rated to 2,000 hp as the name implies.
Part selection is 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.
These short blocks are quick ship items. We normally have them either on the floor fully assembled or machined and ready to assemble. Call us at 815-725-2727 with any questions or to place your order.
In the meanwhile, check out the videos below to see some of our LTs at work.
