Driveshaft question for an R200 differential

[Mikelove]

  I am confused about which driveshaft to use. I am swapping in an R200 diff into my 72 20Z. I had thought that the stock driveshaft pinion flange would swap onto the new differential. That is not the case sadly. The 240z flange is too small. The diff is from a 280z and I am trying to figure out which driveshaft I can use? From what I have read the 240Z shaft is a little too short but I can't really find a definitive answer. Any help appreciated. 

[NewZed]

Is the R200 from a 1975 280Z?  They had an odd flange size.  The other 280Z R200's will swap over directly.  Your original 240Z driveshaft should work with those.  The R180 and the R200 are the same length.

 

The 75 280Z R200 flange is an oddball.

[Mikelove]

 That figures. I don't remember what year the listing said it was from other than a 280z. I just have to find a flange now I guess..Ugg. 

While I am full of questions? What year 280z half shafts do I need for the swap? I keep reading 240 axles will bind and need 280z w an R200 diff to fit properly. Thanks for taking time to help. I appreciate it:)

[NewZed]

The halfshafts are all the same, even the 280ZX shafts.  One of the Hybridz members compared a range of years and determined that, but, unfortunately his web page with the data is gone.  The 240Z's seem to be slightly narrower between the wheel flanges than the 280Z's, but that has not been confirmed.  It's not the halfshafts, it's the cars.  The binding issue doesn't seem to be a big problem but you can find threads about people grinding areas of the halfshafts to shorten them at full compression.

 

In short, all you really need is the correct pinion shaft flange.  Or a 75 280Z propeller (drive) shaft.  

 

Or, maybe there's a flange that you can swap on to your 240Z shaft, see link below.  I haven't gone through the actual measurements so don't know for sure if this guy's parts work.   Some of his information is wrong, like the part about the 79-83 differentials.  76-83 R200's all have the same dimensions, I have had several across the full range.  I've also seen square flanges (78) and circular flanges (76) that fit the same way.  Shape does not correlate to fit.

 

Anyway, worth some measuring.  Check the bolt hole diameters.  Make sure the u-joints will fit.  Good luck.

 

https://jagsthatrun.com/products/adaptor-flange-for-datsun-z-v8

[NewZed]

Here's an old halfshaft thread that covers the length, binding, and shortening.  Might be the best of what's out there.

 

 

Edited 17 hours ago by NewZed

[Mikelove]

 Awesome!! That's a good read. I have been struggling to find that answer. Thanks guys. I really appreciate it!! That solves as lot of problems for me. Now I don't have to spend a million bucks on some odd CV conversion. Least not yet.