JDM Spec S Diff help!

[s15Irl]

Ok I have already done a search with no definitive answers (as most threads have been hijacked by spec r owners)...
So my car have the standard open diff (which is poo), I have gotten a nice freebie s14a UK SPEC viscous lsd.
Is this a worthwhile swap? Bearing in mind its free and I dont want to spend any extra money (plus the mechanic boyfriend will be fitting it also for free!)
The s14 diff has the abs sensor, so thats all good.
Is it just the propshaft thats different? I read another person on here changed that too..

Any info or advice much appreciated! :thumbs:

 

[NeilTSport]

I've recently been looking into this sort of stuff myself but never did anything in the end :wack: So dont take this as 100% fact! (also Spec R owner lol)

I believe the pinion and ring gear are the same so prop shaft shouldn't be a problem. From what i found out i think you will just need the diff and 1/2 shafts (or 1/4 shafts, depends who you speak to) to join to your drive shafts, they will need to have a bolt pattern of 3x2 (3 sets of 2 bolts) as opposed to a Skylines 5 bolt pattern that looks like 5 wheel studs.

Like I said I was looking into it but nothing materialised due to sellers, this is the road i was going down but never tested if it works. If you already have the diff and 1/4 shafts AND free fitting its got to be worth a shot?

I would also be very interested in purchasing your old open diff for welding purposes

 

[NIZAN-R]

spec s have viscous lsd like S13/S14
Spec R auto has same viscous lsd S13/S14
Spec R manual has helical

 

[s15Irl]

Its definitely an open diff.. All Jdm spec s came standard with an open diff, with the factory option of hecical lsd like the spec r.. Mine is definately open!

 

[s15Irl]

I've recently been looking into this sort of stuff myself but never did anything in the end :wack: So dont take this as 100% fact! (also Spec R owner lol)

I believe the pinion and ring gear are the same so prop shaft shouldn't be a problem. From what i found out i think you will just need the diff and 1/2 shafts (or 1/4 shafts, depends who you speak to) to join to your drive shafts, they will need to have a bolt pattern of 3x2 (3 sets of 2 bolts) as opposed to a Skylines 5 bolt pattern that looks like 5 wheel studs.

Like I said I was looking into it but nothing materialised due to sellers, this is the road i was going down but never tested if it works. If you already have the diff and 1/4 shafts AND free fitting its got to be worth a shot?

I would also be very interested in purchasing your old open diff for welding purposes

Ye well I have all of the above available.. Diff, shafts and fitting. Have a 200sx for breaking!
So I think I will just go for it. If all goes to plan and if its not too harsh for everyday use ill sell you my open diff no problem!

 

[NeilTSport]

Good luck with it, hopefully it will drop into the 15 case and be all good, be sure to let us know how it goes!

 

[martydumpvalve]

i just bought an s15 spec s and someone has fitted a two from an s14 im assuming as my speedo doesnt work lol

 

[s15Irl]

Check that your abs sensor is connected its located on the front of the diff housing,it has a 12mm bolt holding it in.
Some s14s didnt have abs so that maybe your problem.

 

[martydumpvalve]

sorry for messing up your thread but i checked the diff and there is no sensor so it must be out of an s14, i have a gear box from my 180 drift car in the garage and wondered if i used the spedo sensor out of it into the gear box of the s15 and conected it to the wire going to the back that was originally for the s15 diff would this work?

 

[s15Irl]

As far as i know they use a different signal.. Your diff is more than likely out of a non abs s14 or a 180sx. I would reckon you'll need to get a diff from an abs s14 or s15

 

[martydumpvalve]

i thought that but was hoping i could sort ot without changing the diff lol

 

[miller]

i've had a s15 with vlsd diff (which originnaly was from r33 skyline turbo at). It worked well in snow/wet conditions but on dry road it became very unpredictable.

 

[A'PEXi]

s15 spec s non turbo version? as long as its 3x2 with abs sensor it should be ok, get some 1.49 shims on either side to replace the standard ones in the s14 diff and you will be laughing