R180
R180 differential is slightly larger, but significantly stronger than the R160 unit used in Datsun 510/610. These are both IRS diffs, and the cases are approximately the same size so swaps are possible with some modificationᴳ. The R180 case is slight wider than the R160 case. The big dog is the R200, but it is much larger.
See also: R160 Swap
Overview
The "R" series of differentials are manufactured by Hitachi and are used by a number of Japanese and European vehicle manufacturers.
Hitachi R180 デフカバー
Long pinion type (N14 Pulsar including RNN14 GTI-R)
2 rear mounting studs + 4 front mounting bolt bosses
180mm ring gear diameter 110mm inner diameter -1976 115mm inner diameter 1977- [stamped K]
Factory fitted to Datsun 240Z/260Z/280Z, 280ZX Skyline 240K, and may Nissan models.
A Subaru R180 can be used but the axle shafts must be modified to suit the Datsun style.
See also: LSD#R180
Gearset
Ring & Pinion sets
3.364 38100-E4600 -76 3.545 38100-78700 -76 38100-U3100 8/76- 3.700 38100-78600 -76 3.900 38100-78500 -76 4.111 38100-E4100 -76 4.111 38100-U3400 8/76- 4.111; 180mm OD, 115mm ID, 10mm bolt 4.375 38100-E4105 -76 4.625 4.875
R180A truck front differential 38100-08G10 -6/86 4.875, 11mm ring gear bolt
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