Reddit mentions of Listening to My Body: A guide to helping kids understand the connection between their sensations (what the heck are those?) and feelings so that they can get better at figuring out what they need.

I Can Handle It by Laurie Wright

Listening to My Body: A guide to helping kids understand the connection between their sensations (what the heck are those?) and feelings so that they can get better at figuring out what they need. by Gabi Garcia

Breathe Like a Bear: 30 Mindful Moments for Kids to Feel Calm and Focused Anytime, Anywhere by Kira Willey

Edit to add a French book: Léon et les émotions by Annie Groovie!

This might be a completely crazy idea, but...since he's clearly smart and enjoys learning, maybe teach him some basic neuroscience? Explain that there are parts of his brain that make him feel his feelings (limbic system), and other parts of his brain that help him stay in control (prefrontal cortex). Explain that as kids grow up, their prefontal cortex gets bigger and stronger so they get better at managing big feelings. Explain that he can help his prefrontal cortex get bigger and stronger by practicing calming himself down when he feels big feelings. He's actually growing his brain every time he practices! (This is more or less true, though it's more about neural connections than brain volume, and obviously there are some developmental limits on what a 4-year-old brain is capable of). Anyway, just thinking this might help motivate him to try a bit more self-regulation, and help him feel less out of control if he understands a bit better what's going on in his own brain. There are some great neuroscience books for kids out there (aimed at slightly older kids, but shouldn't be a problem for your kiddo) such as The Adventures of Your Brain and Your Fantastic Elastic Brain. My First Book about the Brain is another good one in coloring book form.

Helping him become more in tune with his body so he can recognize when he's starting to ramp up might also be helpful. Listening to My Body or Visiting Feelings might help with this. He might also really relate to the story Sometimes I'm Bombaloo. Once he's able to recognize when he's getting wound up, help him redirect that energy/emotion into more appropriate outlets. Maybe encourage him to run around outside, or do jumping jacks, or stomp his feet. You might look into sensory-based activities; this book looks like it might be helpful. Ask him what his body feels like it wants to do, and help him find a way to do that safety/appropriately (e.g. if he wants to destroy something, have him knock down block towers or rip up paper). You could also try calming strategies like deep breathing, yoga, or other mindfulness activities - there are some great apps for that such as Stop Breathe & Think Kids and Super Stretch Yoga, or books such as Breathe Like a Bear and My Magic Breath. He might especially relate to The Lemonade Hurricane. The Mindful Kids activity cards are great too.

Hope something in there is helpful - best of luck to you and your son!