I'm absolutely confused about what Diff I have

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Giselle
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I'm absolutely confused about what Diff I have

Postby Giselle » Sat Oct 10, 2015 12:26 am

I'm parting out my mx5 and the diff is the next thing to go, but I can't work out what it is. It's already out of the car and I've never done any burnouts or donuts to provide extra info.

My car is a 1990 Eunos V-Special auto. In my research I'm getting seriously mixed messages about what it should be. I read somewhere that autos never have LSD but when I look at http://www.goo-net.com/catalog/EUNOS/EUNOS_ROADSTER/3000130/index.html it says:

Transmission: 4AT
LSD: Standard

The 5MT page also says standard. Meanwhile, another spec page for the v-special says "LSD optional"

Alternatively, are there any identifying factors? It's not in the car so I can get a good look

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Locutus
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Re: I'm absolutely confused about what Diff I have

Postby Locutus » Sat Oct 10, 2015 12:43 am


Giselle
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Re: I'm absolutely confused about what Diff I have

Postby Giselle » Sat Oct 10, 2015 1:07 am

I actually read that page! maybe it's just because I've been doing assignments all day and researching diffs all night, but I couldn't make any sense of it. I'll look at it with fresh eyes in daylight tomorrow

93_Clubman
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Re: I'm absolutely confused about what Diff I have

Postby 93_Clubman » Sat Oct 10, 2015 1:55 pm

Viscous LSD or VLSD were a factory option, especially on JDM NA6, but not the more desirable & bigger TorSen LSD, which first appeared in the NA8. Twenty-five year old VLSD now pretty much equates to the standard NA6 diff.

Giselle
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Re: I'm absolutely confused about what Diff I have

Postby Giselle » Sat Oct 10, 2015 3:06 pm

93_Clubman wrote:Twenty-five year old VLSD now pretty much equates to the standard NA6 diff.


Why? Shouldn't a 25 year old VLSD be better than a 25 year old standard diff? I've read that NA8 diffs are bigger though

Fortunately being an auto all of the mechanical parts are in good shape thanks to less power and a lack no history of abuse (can't go fast in an auto mx-5)

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NitroDann
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Re: I'm absolutely confused about what Diff I have

Postby NitroDann » Sat Oct 10, 2015 3:28 pm

The stock vlsd is basically only just able to overcome the torque and traction of the stock tyres on a wet road, its just completely underpowered in its torque controlling capacity in the dry and after 20 years of use they are close to completely unable to do anything. On the hoist you can usually hold one wheel with your fingertips and turn the other wheel with your fingertips.

Consider how strong your fingers are compared to the torque of the engine.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

93_Clubman
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Re: I'm absolutely confused about what Diff I have

Postby 93_Clubman » Sat Oct 10, 2015 4:12 pm

They weren't great to begin with - bit of a mismatch for the NA6 - 1.8 TorSen was better:
http://forum.miata.net/vb/showthread.php?t=360565 (see 2nd post)
viewtopic.php?f=29&t=55912
viewtopic.php?f=29&t=49293
http://www.miata.net/garage/vlsd.html

Giselle
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Re: I'm absolutely confused about what Diff I have

Postby Giselle » Sat Oct 10, 2015 5:22 pm

Based off the ear flanges it looks like it's a VLSD


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