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Scott in Bellingham

R180 3.9 Diff needed , what interchanges?

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I don't know about other brands but the only Subaru 3.900 R180 diffs are found on the JDM STI 6MT cars only. Try the auction site yahoo.co.jp.

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Is 3.90 where you need to go, or where you would prefer to go? Nissan Z-cars came equipped with 3.70's and lower-numerical (JDM had a 3.90).

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Is 3.90 where you need to go, or where you would prefer to go? Nissan Z-cars came equipped with 3.70's and lower-numerical (JDM had a 3.90).

 

Zs are an r200, though, aren't they?

 

 

USDM STis had a 3.9 too. But they're not cheap. in theory the R&P should intherchange

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Zs are an r200, though, aren't they?

 

 

USDM STis had a 3.9 too. But they're not cheap. in theory the R&P should intherchange

 

 

I parted out a few 280zx's years ago and they had r180s.

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hmmm....interesting. Pretty sure my dad's Z31 is an r200.

 

A z31 will indeed have an r200, I didn't say z31, I said 280zx. There are multiple ratios available from nissan, but they are quite expensive.

 

according to the Zcar guys the 720 4X4 from 1/83 to 6/83, had a 3.9 r180.

 

Theoretically the ring and pinion should swap, but without having them side by side, who knows.

 

 

Isaac

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I didn't say z31, I said 280zx.

 

I know. The post I was responding to just said Z-cars. and I don't know them very well, so I was trying to get some clarification. I could have access to a Z31 diff and an STi diff. so if I was mistaken and the Z31 was an r180, I could possibly make a comparison.

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I know. The post I was responding to just said Z-cars. and I don't know them very well, so I was trying to get some clarification. I could have access to a Z31 diff and an STi diff. so if I was mistaken and the Z31 was an r180, I could possibly make a comparison.

 

 

Its too bad the z31 isn't an r180, it sounds like the key to this question is having the STI and non-STI side by side for comparative purposes.

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the only 3.9 diff you will find in r180 came from the early trucks.period.the trick is to get an r200 from a mid 90's z car with the nismo lsd package in it....cheers, b

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the only 3.9 diff you will find in r180 came from the early trucks.period.

 

maybe in a nissan. AFAIK, all subaru r180s are 3.9. at least through 2007

 

 

 

I know all r160 internals swap. I would assume the same would be true with the r180

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maybe in a nissan. AFAIK, all subaru r180s are 3.9. at least through 2007

 

 

 

I know all r160 internals swap. I would assume the same would be true with the r180

 

This is true, for all usdm subaru R180s, but I think over in JDM land you may also be able to find 4.11's and 4.44's if you want lower gearing.

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This is true, for all usdm subaru R180s, but I think over in JDM land you may also be able to find 4.11's and 4.44's if you want lower gearing.

 

All 6MTs listed on this chart (only through 2007), regardless of market, use a 3.9 rear diff.

 

The 4.111 and 4.444 STi options where with 5MTs, which AFAIK, still used an r160.

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maybe in a nissan. AFAIK, all subaru r180s are 3.9. at least through 2007

 

 

 

I know all r160 internals swap. I would assume the same would be true with the r180

we don't have a truck.we have a brat.so of course i was talking about nissan:).

Edited by monstaru

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Things I learned this last weekend at 100 Acre Wood rally:

 

STi axle ratios did change for 2006. So a Subaru 3.9 r180 donor would have to come from pre 2005.

 

The 3.9 r180 in our rally car will need a rebuild before our next event. I may be able to get some measurements of the ring gear for you.

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