I heard a romour that you could put a R31 Diff into a Datsun 120Y, just wondering if this is possible and how big the modifacations would be if any, also whats the price for a R31 Diff.

Same as any diff that needs mods to fit really, get the tail shaft shortened to suit the track width of the car, remove trailing arm mounts and weld in leaf spring mounts while the diff is in a jig holding them in the right spot. I thought Shifty on here is using one in his CA powered Y but can't quite remember

WHY ?????????????????????

What 120y you have? Post 76 should have Borg Warner 68 and they are ok behind ca18,s

Shes a B210 and the year might be 1974, i was thinking about just putting one on her just for LSD but im prob going to just swap the rear axle to a H150 (i think its got a H145 in atm) but then im going to have to shorten the driveshaft.

Im pretty sure the H150's have LSD, if anyone has a better/easier/cheaper way of getting LSD then im all open to ideas.

H150- you should have one inthere already. 120y had h150 or bw 68 in aus 4 door sedans post 76.

They did make h150 LSD but rare and hard to find. Prob cheaper to go bw78 then if you want LSD. I was going to do same but will go bw68 and phantom grip center later on. Bw78 is big and heavy just for LSD. Need big power to make use of it.

well im going to put a GX head in her with a racing spec Camshaft, and SU Carbs it should be pretty good i reacon, its my first project car so im learning step by step, with the Bw78 will i have to shorten it in anyway? and does it have disk breaks?

Bw78 is the R31 diff?

Yes bw78 is r31 diff! But for mild worked a series motor bw78 will be too big, they weigh as much as a a series motor! Lol better off with a phantom grip and finding either a h165 or bw68 in my opinion

Yes bw 78 is r31 diff. You can fit disks to h150 etc. you won't need bw78 with a series, hell its overkill in my l series hence why bw68. $450 for phantom grip later on.