The BMW 3 Series Performance Guide discusses modifications one can make to any production model E-30 BMW. That's the 3 series from 1982-1994, or "the last of the beautiful boxy body style" as I like to think of it. I heard about the book after Lance Richert gave a glowing review of an advance copy. [Lance puts on a gathering each year called the E-30 picnic, which I have attended several times. It started as a small gathering of three dozen cars at a park in Bellevue and is now a national gathering with over 200 cars.] The Performance Guide is broken up by topic: suspension, engine, transmission, etc. Then it goes into detail for all of the different variations of the series [e.g. 325e, 318is]. Lots of good details. Some of the purchasing advice seemed a little generic [could have been about Nissan 240's]. The engine swap information was very useful to me as I plan for the day when I finally blow mine at redline. One error I did consider annoying is that they talked about Downing Atlanta making a super-charging kit for the M42 engine (which I have). Ten years ago the Downing website talked about M42's in later body styles (the Z3 as I recall). Then the supercharger they used became NLA. While I found some rumors it might have come back for a bit, an M42 supercharger is the unicorn of the 318is world. Stop getting my hopes up! That said, I found the book useful, inspiring, and well worth my time.