Book excerpt: After nearly 20 years of production, the GM LS series engine is wildly popular today. Not only have these engines proven to be durable and reliable but they are also a fantastic platform for modification and for swapping in older chassis. With millions of used engines in salvage yards, the available number of cores or assembled engines for a reasonable price has never been higher. While General Motors has updated the platform repeatedly over the last two decades, usually a good thing, the sheer number of changes has created an environment that it is really confusing to the average hobbyist. With these engines being very modern, the concept of what fits with what is beyond the scope for most without some serious help. In LS Engine Parts Interchange: 1997-Present, LS author and expert Joseph Potak talks you through the myriad of options when looking at this complex platform. Text covers engine blocks, crankshafts and rotating assemblies, cylinder heads and valvetrain for both cathedral port and rectangular port heads, camshafts and componentry including VVT technology, oiling systems, induction and injection, electronics and engine controls, superchargers, external engine accessories, and more. Before jumping into a swap, selecting a salvage yard motor, choosing a crate motor, converting Gen III heads to Gen IV, or swapping any components for performance improvements, make sure you have this book handy. It will prove to be a valuable resource for years to come.