The Porsche 917 celebrated its 30th birthday a few years ago, is marching relentlessly toward the big 4-0, and there has still been no other car that has come so close to embodying the pure spirit of racing. Initial tests were somewhat hair-raising - driver Rolf Stommelen would get out of the car, smile for the cameras, say all the right things, and then be led off, shaking, to lie down in a darkened room and recover. Even after some of the more chronic stability problems were smoothed out (to a degree), the car was a handful.

"It was grossly over-powered for its diddly little 10-inch rims," Australian Frank Gardner was quoted as saying on page 55. "The computer said that they would be man enough to do the job, but the computer wasn't strapped into the hot seat guiding the thing around the Eifel Mountains."

From such a beginning, the endeavour, ingenuity and politics that conspired to turn an unstable, horrendously over-powered rocket into something sufficiently driveable that you could nurse it through the corners and then blow everybody into the weeds down the straight make for a great story. It's even more of a credit, both to the 917's original design team and to those who adapted them later on, that it went on to have a comparatively long career under some very different regulations. From its Sports Car origins to its final incarnation as a Can-Am juggernaut, it's almost as if the designation 917 marks an era, rather than a mere race car.

Morgan's account of the 917 story is extremely well-written, with its only flaw being an occasional leaning towards the romantic. Balance this out against everything that is good about the book, though, and there is no contest.

"It was never my intention to produce a book which was a dry reference of specifications, race victories and so on," says the author in his acknowledgements, and this is yet another aspect of the book that distinguishes it from many others of the genre.

Nobody, as far as I can tell, sets out to write a boring book, and of course it has to be taken into account that the question of what is and is not boring is highly subjective. But in past Bookworm Critique columns, other titles have been criticised for being little more than annotated race results interspersed with a few photo panels, and I think that this book justifies those criticisms by showing just what can be done if the subject is approached a little differently.

Through the various people that Morgan spoke to during his research, one gets the impression that the author developed a strong 'insider' perspective of the various mechanisms that helped get the 917 program up and running, and this is conveyed to the reader. Chances are that you weren't there when the 917 was conceived, designed, built and raced, but this book seems to offer a pretty solid impression of what was really going on behind the walls of the Porsche headquarters.

For added perspective, Morgan's focus is sufficiently wide to encompass the other racing models that were contemporary to the 917 at Porsche, which offers a clear look at how the marque was operating during one of its true glory eras.

The other standout are the photographs, which are numerous, diverse, and astonishingly comprehensive. No matter what small variation was made to any given 917, Morgan seems to have been able to source shots of it. It's probably safe to assume that a lot of these images had not been published prior to this book hitting the shelves, adding yet another gold star to an already mightily impressive effort.

Is this the definitive 917 book? I'm no Porsche expert, but I can't imagine how this book could be topped. For my money, it is in the running as one of the all-time great accounts of one particular car. Anybody with even the remotest interest in Sports Car racing needs to own this, and F1 fans who have ever shown even a fleeting interest in Le Mans - and even those that haven't - should probably track a copy down.