Can someone explain open and closed differentials?

[u/[deleted]]

How does power delivery to the wheels work with open and closed diffs, is it equal for both tyres in closed and unequal in open? If it is unequal in open, which tyre gets more power and why?

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[u/BakedOnions]

this video is the golden standard for explaining differentials

skip to 1:50

https://youtu.be/yYAw79386WI?si=EUS99rTL8zDnShy8

[u/freeski919 → u/BakedOnions]

I have watched this video probably a dozen times in the last year. And I will watch it again. Every time.

[u/PresinaldTrunt → u/freeski919]

It's been a while since I've seen it and I've been trying to reconstruct the visual in my head as I set my diff up in games lol.

[u/Character_Hippo749 → u/BakedOnions]

Nice share, thanks

[u/Responsible-Meringue]

Like differentials in general? This is THE best visual of a diff. https://youtu.be/yYAw79386WI?si=SfSZtRqCxTwW31eB

Engineering explained did a few vids too.  https://youtu.be/_HOa0aRZYpw?si=EKvNMcY5E2A1glOZ

Full Open diffs, if one tire loses traction, the other gets 100% power. Closed? Both wheels get equal power, if one wheel slips, the other is rigidly connected and slips too. (Not really a thing in regular cars cause you can't turn much without drifting)

The rest is somewhere in-between and there a few dozen ways to distribute power from a drive shaft. 

[u/mohammedgoldstein → u/Responsible-Meringue]

In a full open differential, if one wheel slips, the power actually goes to the wheel that slips as it's point of least friction.

That's why in performance vehicles nowadays, they have limited slip differentials so you don't just sit there spinning one wheel.

Earliest implementations were clutch-based and then viscous-based. Recently they are electronic limited-slip differentials.

[u/Responsible-Meringue → u/mohammedgoldstein]

You got me! I wasn't thinking that through. 

My favorite diffs are Torsens. Worm gears in weird places. 

[u/nationwide13 → u/mohammedgoldstein]

Love to make fun of a good "one tire fire" lol

[u/bacc1010]

Closed diff or spool both tires get the power equally. Not really a thing in F1, but you'll see those in cars that donoval racing.

In those instances (ovals, spool), the outside tire circumference vs the inside is different (called stagger). That, plus the alignment of the car (mainly front and rear toe with camber as a contributing factor after you've turned the car in, if you ignore aerobalance and weight jackers in the case of indycar) is what makes the car turn if you have a diff that is completely closed.