SCORE Journal - The Official Publication of SCORE Off-Road Racing
Issue link: https://read.uberflip.com/i/485293
advantage. Simply put, engines are air pumps at their most basic, and like the original small block V-8, the LS architecture offers comparable displacements and the same number of cylinders opposed by a 90-degree angle configuration. But when it comes to pumping air in and out, the LS heads offer a tremendous advantage over the older-style Chevy engine cylinder heads. The design enables the LS engine to rev higher and process more air, which results in big horsepower gains. Consequently, LS engines typically respond very well to comparatively basic enhancements, such as camshaft changes that hold the valves in the heads open longer. In fact, the basic 6.2L (376 cubic inch) LS3 crate engine from Chevrolet Performance, is rated at 430 horsepower. This is more than any production version of a Gen 1 Chevy small block that has ever been produced. That basic camshaft upgrade, along with a few additional changes, results in a 525-hp version of the LS3 platform, dubbed the LS376. This gives racing vehicles a tremendous power-to-weight advantage from an engine that simply is lifted out of the crate it was delivered in and installed in the chassis. “It’s pretty common to get 800 or more horsepower from a naturally aspirated LS racing engine,” says Turn Key’s Enger. “That was unheard of years ago with old-school small-block Chevys and other engines.” The LS Family Tree The LS engine family debuted in 1997. General Motors called it the Gen III small block, with iron-block versions in trucks and the all-aluminum LS1 version introduced in the then-new C5 Corvette. A year later, the LS1 replaced the LT1 small-block in Camaros and Firebirds. The LS1 displaced 5.7 liters, similar to the previous-generation small-block, but the cubic-inch measurement differed slightly. Displacements totaled 346 cubic inches for the LS1 versus the traditional 350 cubic inches. In 2005, the Gen IV branch of the LS family was born, with performance versions including the LS2, LS3, LS9 supercharged, and LS7 engines.The most distinguishing differences between Gen II and Gen IV cylinder blocks are larger bores (on some engines), different camshaft position sensor locations. The front timing cover area on Gen IV blocks and top-rear position on Gen III blocks were also different, and on most Gen IV blocks,