Differential Differences?

[MA70witBoost]

Ok, I would like to open up a discussion on differentials... Im looking to replace the differential i have. My Pumpkins Oil Seal is leaking gear oil and who know's what damage the diffs gotten in its 20 years in existance. What are the differences between the differentials bellow? I know about the 1 way, 1.5 way, and 2 way LSD stuff... But Selective, Mechanical, and Helical LSD?? Heard the terms befor just not familiar with them. I plan on getting the MA70's known in the drift scene... Just trying to see what helps me out with that. :thefinger

 

[hawk]

well i know for a fact that the selective lsd uses clutch discs stacked in different arrangments to create different settings. ie. higher or lower initial torque. i also hear that they need to be rebuilt qutie often from what i under stand and my whatings of best motoring videos and the like.

 

[Red Dragon]

someone real smart explain the differences between them for everyone first

 

[IJ.]

No idea about Drifting but the Torsen is the diff of choice for me as it doesn't induce understeer and has made the biggest single change in my cars handling!

 

[3p141592654]

You can start with this paper that explains the Torsen in great detail and compares to conventional differentials. It is by no means the nice tight summary you are asking for, but if you put in the effort you will come out knowing a great deal more about what a Torsen diff is all about.

http://www.torsen.com/files/Traction_Control_Article.pdf

 

[garagefujimoto]

The torsen diff indeed reduces understeer, but does not lock up hard on braking. If you like to turn in sharp and then power out, it does a good job of reducing front understeer and the putting the power down evenly. I like to slide all 4 wheels and lock the rear end on braking so it doesn't work as well for these high-speed dynamic moves.

Selective diffs allow for a change from open to lock, 1.5 way to 2 way or differing hardness.

Torsen is helical.

I'm not sure what you mean by mechanical

 

[IJ.]

In every day low speed driving the Torsen doesn't understeer like a Clutch Diff.

Guess I should have been more specific......

 

[Red Dragon]

You can start with this paper that explains the Torsen in great detail and compares to conventional differentials. It is by no means the nice tight summary you are asking for, but if you put in the effort you will come out knowing a great deal more about what a Torsen diff is all about.

http://www.torsen.com/files/Traction_Control_Article.pdf

holy crap, I got thru the first two pages, will read the rest when not at work... thanks, looks informative

 

[jdub]

Here's a little more light reading for ya... :icon_bigg

http://www.jza70.com/articles/diffs_lsd/index.html

 

[xarewhyayen]

Not to jack the thread, but if i were to change from 3.73 to 4.30 lsd, what would i have to change for my speedo to read correct?

 

[Jeff Lange]

speedometer drive and driven gear (means disassembling the transmission), also, I don't even know if the correct drive gear is available.