will s13/s14 diff fits into s15 pumpkin (spec-r, 6 speed, HLSD)

[SR2oD3T]

fact of my 240sx

S14 with full S15 spec-r swap. 6 speed along with S15 pumpkin with HLSD.

i m upgrading to a 2 way LSD but looks like i can find an s13 or s14 2 way LSD much easier.

i've done the research knowing that s15 HLSD can swap into s13 s14 with the matching S15 half shaft (basically i m doing the other way around). so i m pretty sure i can put in a 2 way LSD for either s13 or s14 into my spec-r pumpkin with the s13/s14 half shaft (which i have some spare).

only a small catch is, s15 uses 13mm ring gear bolts and s13/s14 uses 12mm. which means the S13/S14 diff will have a smaller holes on the LSD?!

any solution on this? send it to machine shop to enlarge the bolt holes on the lsd?? (i feels kinda scary)

i can get a great deal on the S13 LSD but i don't wanna get stuck with the parts that i can't use.

thank you. appreciate it.

[Croustibat]

Use S13 bolts. I went the other way (S15 helical in my S13), we used the S13 bolts with the S13 crown on the S15 HLSD and its ok.

BTW you dont want the S15 crown and pignon. If you can ditch them and get an S13 one, get it (S14 and S15 are 3.7, S13 is 3.9).

You should also prepare to get a new gearbox. The 6spd is known to break easily, not sure the added strain of a clutch type LSD is going to help it survive for long.

I heard nismo makes bolts to fit the S13 crown on the S15 diff that would be a perfect fit too.

[SR2oD3T]

thanks for the reply.

i have the full spec-r swap with 6 speed so i think the final gear works for me.

yea i heard the 6 speed are a little weak but i m running mostly stock, that should be fine for a long while.

only problem i have now is the ring gear bolts.
does the S15 13mm bolts able to go through the s13/s14 LSD bolt hole (tomei 2 way LSD for s13/s14) and bolt on to my s15 ring gear?

or the stock s13/s14 12mm ring gear bolts be able to bolt on to s15 ring gear?

thanks for the advise.

[SR2oD3T]

Anyone can help？ thanks！

[jr_ss]

They sell 13mm x 12mm bolts... Egay has them.

[SR2oD3T]

bolts are not a problem for me. as i have both 12mm and 13mm bolt (i have both s13 and s15 complete pumpkin)
i got a deal on a tomei 2 way diff for s13/s14 open diff, just wanna make sure the 2 way fits into the ring gear of the s15 spec-r with 6 speed.
thanks.

[jr_ss]

The ring gear is for 13mm bolts, most likely the diff has 12mm holes.