The majority of the book is a near verbatim novelization of the as-filmed movie "American Graffiti". The prologue and post-"Graffiti" story-telling is entertaining and faithfully continues with the characters' personalities. But, it suffers from some story discontinuities (i.e., re John Milner's last race) and mysterious spelling inconsistencies with a character's name ("Vikki" vs "Vikkie").
Bare bones novelization, makes you realize its all in the delivery of the actors. Not much detail of the night and in the second half day, just dialogue. Makes me appreciate the films even more. Except for a questionable ending, that has a surprise "really?" ending not much to this