Yeah, sometimes finding the exact book is quite a challenge, and even finding one that is close can be hard. Sometimes you have to look for ones that you hope will be related; books about Honda engines will likely be more beneficial than the Ford FE series but I have yet to buy a book that I didn't get something out of, even though it was only a sentence or two. A synthesis of all the books you read is going to form the basis for your understanding of engines. That's why I have so many (about 100)!
I also have Heywood's book and find myself referring to it more often than I initially thought I would; great on theory but not very specific about the how-to. For that I dig out the S-A Design (Cartech books), HP Books, and sometimes the Motorbook Powertech Series books and reread the pertinent sections. Look up the book lists for each of those and you should be able to find books that will fill in the gaps.
Two EFI books to start with might be SA 135, "Engine Management - Advanced Tuning", and SA 161, "Designing and Tuning High-Performance Fuel Injection Systems", both by Greg Banish. Be aware that most books will contain a lot of the same material and by the same author but is presented slightly differently depending on the focus of the book. I find a good author that presents things the way I like and purposely buy more, even on the same subject because one usually leads into the next. These two books are an example of that, with his first book being more of an intro and the second leading into the application.
I also try to find another author on the same subject, to compare and verify what is being stated and also to fill in some gaps that might have been left by the other author. Again, that's why I have so many books and have found every one of them to be well worth the $20 (or so) purchase price. I go to swap meets and look for old engine books too; sometimes $1 will buy you a priceless blast from the past, like "Hot Rod Carburetion and Fuel Systems", circa 1964 with the exotic period-correct induction systems described in detail, ideal for someone like me who in addition to building engines for current national series builds hot rods and such during the winter months. You never know what someone is going to insist on having!
Airflow is (almost) everything, and figuring out how to pack the air in is a life-long pursuit. The interaction between cam timing and intake/exhaust resonance will likely be of most importance to you re: the motorcycle engines, and that still seems to be as much art as science although it's much better understood these days. There are some older books on the theory; "Scientific Design of Exhaust and Intake Systems" by Philip Smith, 1971, somewhat dated but a good primer.
You're very fortunate that there are so many books out there now; when I started thirty years ago most of the info was scattered through the various car magazines, and I had maybe ten actual books to choose from.