HYPER REV Books are more like tuning guides for specific vehicles. Each book is packed with hundreds of parts ranging from aero parts, engine performance, suspension, wheels, and more. The text is all in Japanese and there are no translated versions at this time, so you better brush up on your Japanese. Some volumns are currently out of print, so if you see one your interested in, it's best to pick it up NOW! HYPER REV sometimes publishes several books on a particular vehicle, but each edition is different, depending on the generation focus, say a S15 vs S13/14 of the Silvia. They even have tuning guides available for some SUVs like the 4Runner aka SURF in Japan.