Alex Wellerstein is a historian focusing on nuclear weapons and the government structures surrounding them. He mentioned this book in his newsletter Doomsday Machines (which is outstanding if you're interested in nuclear history) so I tracked it down on the Internet Archive and...yeah. Oh boy.
The foreword by Spider Robinson extols Dean Ing as a veritable combination of Howard Hughes and Doc Savage: engineer, race car driver, backpacker, polymath, and survivalist. There's more than a fair whiff of bullshit about it (do I really believe the guy built from commercial parts a car capable of 50+ miles to the gallon?), but it sets expectations appropriately. We're told Ing is a guy who writes entertaining science fiction mainly as a vehicle to promulgate valuable information to help people survive the inevitable nuclear war, and that this won't just be an entertaining novel, but also a lifesaving manual of important tricks for surviving doomsday. Unfortunately the most important survival tips seem to be "have a flying car so you can dodge traffic on your way home from the apocalypse" and "having a highly-skilled NASA engineer brother-in-law who can figure out how to solve all of your problems."
Wellerstein makes this point in his newsletter, but it's something any fan of the post-apocalyptic genre has probably noticed: for the story to be exciting, survival has to be in doubt and the heroes have to overcome problems, but this is at odds with the idea that the heroes are preppers. Main character Harve Rackham has dug a fallout shelter tunnel beneath his house because he knows World War III could come any day, but he hasn't bothered to install filtered pump to provide air, or a basic toilet, or any kind of water storage or even much in the way of food. His sister's family plan to use their bicycles to escape danger if roads are blocked, but they let their son's bike fall into disrepair to the point it's unusable when they need it. This creates more drama in the story, but also makes the characters less believable as serious people planning to "pull through."
Ing's politics are also a bit unpleasant to my eye. It's taken for granted in most post-apocalyptic survival stories that cities will be deathtraps and one's best bet is to have some kind of rural redoubt. Harve Rackham doesn't spare much energy caring about the people dying in the Bay Area who didn't have the good sense to buy a home in the country like he did. He also worries that the softness of modern living (including features such as not beating your kids) has made the younger generation soft, maybe too soft to survive. It's not as bad as it could be, but there's an element of moral scold about it that wearied me, especially since so much of the narrative depends on Rackham and his gang being lucky or otherwise having plot armor to survive.
The book is half novel and half a collection of how-to essays on nuclear survival. Some of those go in weird directions, like explaining how damming up sea water and letting it evaporate off repeatedly can be used as a source of salt, ignoring the fact that this would almost certainly be enormously contaminated by fallout and that in an all-out nuclear exchange there might be plenty of surplus salt available owing to everyone being dead. It's a bit of perverse fantasizing that probably qualifies as whistling past the graveyard.
Interesting to read as a historical piece, but its present obscurity is perfectly understandable.