2005 Subaru R180 LSD swap into 75' 280z with oem r200

[280Z-75]

I know there are plenty of threads related to this swap into a 240z. I used the Wolf Creek Racing adaptors.

Here's an issue no ones mentioned so far, and that is if you're putting this into a 280z, you'll have to get a new driveshaft with an input flange that matches the R180 Subie diff. I realize now most car guys probably already knew they would need a new driveshaft made.  It's not a direct swap even if you have a 240z with an r180. Bolt spacing for the subie input flange and 240z driveshaft are different.

I had the 240sx 5 speed tranny conversion, and had my 1975 280z driveshaft shortened to mate to my r200....which I was no longer able to use since the bolt spacing did not match up to the subie r180.

The 75 280z's r200 input flange is larger and is not a direct swap over to the subie r180 either. Extra cost your might not be thinking about....

Couple of options:

Redrill the subie differential input flange to take the 280z driveshaft bolt spacing....(may not be balanced)

If you have a 240sx transmission in your Z, buy the one piece 240sx driveshaft, and have a driveshaft shop shorten it.  I believe the bolt spacing should match the subie r180.

Have a driveshaft shop replace the flange of your current driveshaft with one that has the correct bolt spacing for the new subie r180.

Or take the route I went with, just have a whole new custom driveshaft made :).

 

 

Edited January 11, 2019 by 280Z-75
Correct some misinformation about needing an r180 input flange from a 240z

[jhm]

Yeah.....I think most people that have done this swap are merely replacing their open R180 with an LSD R180, which avoids the issues you're running into.  The input flange from any S30 R180 "should" work (i.e. I don't believe it needs to be from a 240Z).  

 

And yes, the shorter R180 would nominally require a longer driveshaft than an R200.  However, keep in mind that Datsun moved the differential rearwards in the middle of the 240 production years (I think between '72 and '73).  This change improved the half-shaft angles, but resulted in a different mounting position for the diff.

 

What year is your car?

[NewZed]

1975 280Z's have the oddball R200 pinion flange.  It has its own unique bolt pattern and bolt size (might be the same as the 300ZX's, not positive.  Definitely not like the other Z cars though).  So if you cut a 1975 R200 driveshaft, it's only good for 1975 R200's.  Beware the 1975 R200.

 

And the R180 pinion flange location in the car is not different than the R200 (I've never had an R180 but all signs seem to show this).  You can swap an R180 for an R200 and use the same driveshaft.  Except for the very early 240Z's with the forward-mounted diffs, that use a shorter driveshaft (which is usable with the 240SC/71C swap though, except 1975 cars).

 

A good general reference - http://www.zhome.com/ZCMnL/tech/R200.htm

 

And a couple of excerpts from the 1978 PD chapter.

 

 

[evoog]

Pretty sure driveshaft shops can just order the flange from the driveshaft to a r180, and weld it onto your existing driveshaft. May be wrong, but my driveshaft guy had catalogs full of them

[BluDestiny]

They should work. I'm going off this picture,

 

 

and this thread: http://www.zcar.com/forum/10-70-83-tech-discussion-forum/278098-r200-input-flange.html

 

I currently have an r200 in my 240z, and will be swapping over to using a subie r180 to reduce weight. Going with a TTT diff mount, and redoing all the the suspension as well. I hope I don't get unlucky and have the abnormal pinion flange. 

[RebekahsZ]

If you can, get the flange on the far right in that pic. It is easier to get a wrench on.

[NewZed]

One more thing - square versus round doesn't tell the story.  I have square and round flange R200's, both use the same bolts and have the same pattern.  I've had them both in the car.  One from a 1976 280Z, the other a 1978 280Z.  Don't know why, but it is.  You have to measure.