Miata Tech: Torsen LSD

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Georgethefierce
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Miata Tech: Torsen LSD

Post by Georgethefierce » Tue Oct 24, 2006 3:52 pm

use small words when explaining 'cause I'm not that bright...

I'm having traction issues in 3 (NHIS)..... now my car supposedly has a Torsen LSD from a 1.8 Miata in it.....

my biggest issue is getting on the power in 3 and then spinning the inside tire all way up the hill..... shouldn't the torsen prevent this?

I realize that I need to enter slower and excellerate up the hill, but I seem to have a bear of a time getting up there

if anyone has followed me up there and noticed anything I'd appreciate it (I'm the red/white angrypork miata #07)

or maybe I just need a lesson on what a Torsen actually does.
J
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MiataSteve
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Post by MiataSteve » Tue Oct 24, 2006 6:26 pm

Some ?? info here....about 1/2 way down page;

http://www.miata.net/garage/vlsd.html

I have a VLSD unit in my '90. I was getting lots of wheel spin and 4 wheel drifting up the hill last weekend....never drifted (Fast and the not so Furious?) up the hill before. Track conditions? Or where we just faster than usual? :roll:

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Post by Dave_G » Tue Oct 24, 2006 6:48 pm

I also have a '90 Miata with a Torsen LSD from a 1.8. The inside wheel spin you describe doesn't sound to me like normal behavior for a Torsen. The again, maybe I just don't push my car hard enough. :P When you say it "supposedly" has a Torsen, how sure are you?

Torsen is short for Torque Sensing and it works like this: The diff will supply up to 2.5 times the torque to one wheel vs. the other. So, whichever wheel can handle less torque before spinning (usually the inside wheel), the other wheel will get 2.5 x that. For example, if the inside wheel will spin with 100 foot-pounds of torque, the outside wheel will get 250 foot-pounds to pull you up the hill.

It's worth noting that with a Torsen, if you lift the inside rear completely off the ground (not a common thing in a Miata), or if it's on ice (not on the track, I hope!), it takes close to zero torque to spin it, and 2.5 x zero is zero, so the outside wheel will get no power until the inside wheel gets traction again.

Georgethefierce
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Post by Georgethefierce » Wed Oct 25, 2006 7:27 am

Dave_G wrote: When you say it "supposedly" has a Torsen, how sure are you?
I was told it had one when I bought the car.......i will take the dif cover off this weekend to see what is actually in there......from talking to other people it seems to be acting an awful lot like an open dif.
J
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Crusin
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Post by Crusin » Wed Oct 25, 2006 9:36 am

Hi Jason, there is no cover to remove, you have to pull the entire diff. Maybe the problem is the color you have chosen for the paint job. Mary Kay decals anyone...? :tweety:

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Post by Georgethefierce » Wed Oct 25, 2006 2:58 pm

Crusin wrote:Hi Jason, there is no cover to remove, you have to pull the entire diff. Maybe the problem is the color you have chosen for the paint job. Mary Kay decals anyone...? :tweety:

BLAH!!!! pain in the ass...... and you'll see the only tougher thatn a dented and scraped miata....is a pink one!
J
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Stynger
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Post by Stynger » Wed Oct 25, 2006 3:36 pm

Georgethefierce wrote:
Crusin wrote:Hi Jason, there is no cover to remove, you have to pull the entire diff. Maybe the problem is the color you have chosen for the paint job. Mary Kay decals anyone...? :tweety:

BLAH!!!! pain in the ass...... and you'll see the only tougher thatn a dented and scraped miata....is a pink one!
Jason,

Pull the fill plug and look inside with a light.

If it's a Torsen, you should see worm type gears in a vertical position.

An open diff has bevel cut gears.
Les.

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Drive it like you stole it!

Georgethefierce
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Post by Georgethefierce » Wed Oct 25, 2006 3:42 pm

thanks les....I'll try that
J
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zip4zat
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Post by zip4zat » Wed Oct 25, 2006 4:25 pm

GTF, its not just you...
I spun all 4 wheels around 3 and all the way up the hill all weekend, and I think Ive got a gaggle of diffs in my car... ask Raj, he was staring at my passenger door up the hill every lap that he was behind me.
Joe Lu
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Georgethefierce
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Post by Georgethefierce » Wed Oct 25, 2006 4:26 pm

zip4zat wrote:GTF, its not just you...
I spun all 4 wheels around 3 and all the way up the hill all weekend, and I think Ive got a gaggle of diffs in my car... ask Raj, he was staring at my passenger door up the hill every lap that he was behind me.

you also have 200 more HP!
J
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zip4zat
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Post by zip4zat » Wed Oct 25, 2006 4:36 pm

what I meant to say is that I think it was more the track conditions because I usually dont get that much slip around 3 and this weekend it was very different.
Joe Lu
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Georgethefierce
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Post by Georgethefierce » Wed Oct 25, 2006 4:59 pm

gotchya, i tried to contact Kevin to make sure I wasn't hearing things....just trying to figure out if I have a problem or i'm just missing the part itself.
J
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JayBay
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Post by JayBay » Wed Oct 25, 2006 5:04 pm


RyanC
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Post by RyanC » Wed Oct 25, 2006 5:09 pm

zip4zat wrote:GTF, its not just you...
I spun all 4 wheels around 3 and all the way up the hill all weekend, and I think Ive got a gaggle of diffs in my car... ask Raj, he was staring at my passenger door up the hill every lap that he was behind me.
I think you took the concept a bit overboard at the end of the day, Joey...

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zip4zat
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Post by zip4zat » Wed Oct 25, 2006 5:19 pm

I knew this was coming...

actually found a loose nut that was the source of my problems 8)
Joe Lu
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