SDPC Raceshop Builds 830HP Naturally Aspirated Gen V LT1

When it comes to making big horsepower numbers with the LS and LT platforms forced induction seems to get the most attention. However, most enthusiasts would likely agree there is something special about a big cubic-inch naturally aspirated engine making almost 2 horsepower per cubic inch (1.89 to be exact). Scoggin Dickey’s engine building department, known as the SDPC Raceshop, recently shared video of its latest test mule that is a beast of a power plant.

Images and video courtesy of Scoggin Dickey Parts Center

For the past ten years, the SDPC Raceshop has produced high-horsepower engine combinations known for their reliability and proven performance. Although LS engine builds are still the most popular, the Raceshop has been busy developing and testing various Gen V LT engine combinations for several years now. They have even shown the Gen V LT platform is capable of 2,000-plus horsepower by combining the L8T iron-block and forged factory crankshaft with a pair of turbochargers. As much fun as boost is, the Raceshop team changed things up for this engine build and assembled a naturally aspirated combination.

Starting with an aluminum Gen V LT block, the factory sleeves were removed to make way for longer cast-iron sleeves in preparation for the 4.125-inch stroke crankshaft. The longer sleeves offer better support of the piston at bottom-dead-center in an application such as this that has a long stroke. While they were at it, the Raceshop machinists bored the new sleeves to a 4.125-inch diameter. Filling the cylinders are Wiseco pistons made specifically for this engine project. They feature a custom dome design developed by the Raceshop team along with vertical gas ports to help push the Wiseco GFX rings against the cylinder walls for a better seal. The custom pistons result in a compression ratio of 15:1. Completing the short-block assembly are 6.125-inch long Molnar forged-steel connecting rods. This combination results in an impressive 440 cubic inches.

When trying to make a lot of naturally aspirated horsepower the cylinder heads and camshaft are vital to success. For this LT engine, a pair of Chevrolet Performance COPO Camaro cylinder heads were put to work. The COPO heads were developed by the Performance Racing Center at GM Racing and are LT1 units that have been given a proprietary CNC porting treatment. The Raceshop team assembled the COPO heads with an SDPC dual-spring kit…