JDM diff type?

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RS2000
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JDM diff type?

Postby RS2000 » Fri Jun 13, 2014 6:26 pm

What factory diff came on a JDM '99 NB (NB8C) with a 6 speed gearbox ?

Open or viscous lsd or torsen? Ratio?

Thanks in advance

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Regie
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Re: JDM diff type?

Postby Regie » Fri Jun 13, 2014 8:05 pm

3.9 Torsen as a guess
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hks_kansei
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Re: JDM diff type?

Postby hks_kansei » Fri Jun 13, 2014 8:41 pm

Could be anything, Japan you could option different ones.

'99s were 4.1 ratio, but I;m not sure if that applied to the 6 speed.

As for the diff type, could be open, or torsen.

If it's from an RS (which I expect it is, since it's a 6 speed) it's more likely to be an LSD since I think they were standard on the RS.
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zossy1
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Re: JDM diff type?

Postby zossy1 » Fri Jun 13, 2014 11:57 pm

hks_kansei wrote:Could be anything, Japan you could option different ones.

'99s were 4.1 ratio, but I;m not sure if that applied to the 6 speed.

As for the diff type, could be open, or torsen.

If it's from an RS (which I expect it is, since it's a 6 speed) it's more likely to be an LSD since I think they were standard on the RS.


Are you sure? Dad pulled an open 4.3 out of a 99 JDM NB8C (5 speed) last week. No doubt it was factory installed.

I know the ADM was 4.1 but I suspect the car we have was representative of all JDM 5 speed 99-00 NB8Cs.

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Re: JDM diff type?

Postby emily_mx5 » Sat Jun 14, 2014 9:02 am

Gotta be careful with your series names, all jap NBs are called nb8c (part of the vin)
Where are we use nb8a/nb8b/nb8c to distinguish them.
So you are talking about a jdm nb8a in both cases, pretty sure the RS had a torsen diff.


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timk
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Re: JDM diff type?

Postby timk » Sat Jun 14, 2014 10:33 pm

I think all 6 speed NB JDM MX-5s have TorSens.

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Re: JDM diff type?

Postby spikey » Tue Jun 17, 2014 12:05 am

The JDM NB's with 6 speeds ran the 3.9 Torsen unlike the ADM with the 3.63 open diff, I don't think any of the JDM models had an open diff, they were all sent here instead :cry:

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Re: JDM diff type?

Postby RS2000 » Tue Jun 17, 2014 9:53 pm

Thanks for all replies - seems it's most likely a 3.9 Torsen.

The car has a 'Roadster' badge - I assume that's what you mean by 'RS' ?

Cheers

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Re: JDM diff type?

Postby emily_mx5 » Tue Jun 17, 2014 10:24 pm

No.
Roadster is the Jap name/badging.
RS was a particular model in japan, special edition with lots of goodies.


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david_syd_au
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Re: JDM diff type?

Postby david_syd_au » Wed Jun 18, 2014 8:39 am

A 1999 Roadster RS would also have yellow bilstein shocks, and probably ABS
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