I've got a 1971 240Z with an R200 rear and a SBC 383 stroker motor. The beast is making around 450 HP and has worn out the rear end. I'm looking for a source who can provide a new ring and pinion set hopefully with a ratio of 3:70 (It currently has a 4:ll in it and that's to much). I'm open to any and all suggestions.

I think that I saw your post on another forum about the same issue. It will be much easier to just source a complete R200 differential. You have to take the whole thing out anyway to replace the ring and pinion. They're not like Fords or Chevys that can be serviced from underneath the car.

The easiest direct replacement for you would be a 3.7 R200 from a 1979 280ZX. Everything will be the same as what you're using now (unless somebody swapped in a 1975 R200, which are unique in the driveshaft bolt pattern). Second easy is a Z31 R200. You'll need to swap the pinion flanges because the Z31's use a different bolt pattern (oddly, they use the 1975 280Z bolt pattern, apparently).

If you want new there's always Nissan. Spendy. Here's the cost of a 3.54 ratio R200 - CARRIER-W/ :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com You'd have to ask around to get the part number for a 3.7.

Good luck.

Edited April 14, 201410 yr by Zed Head

New R&P for long nose R200s are basically NLA. You might get lucky if you call Nissan Motorsports directly and they can find something on the shelf.