Salt, I have been a backyard mechanic/ala race car "guru" for over forty years, and I have never seen or had anyone explain what this short video has.
Not only do I thank you, but your sharing it shows that whether it is high tech or basic tech, we can always learn something new!
Let me add, topics like this are one more reason to SUPPORT THIS SITE with a Cash Donation to keep it happening.
If you don't, chances are that Nancy (Mrs. Slim) will be unable to buy new summer wear, and may show up with tattered (or holey) clothes........... wait a minute, cancel my suggestion.................. Bob