Differential Options:

[veilside180sx]

If you aren't making a bunch of power, there is nothing wrong with the VLSD. The clutch diffs are nice, as are the helical. If you do cave on the clutch diff...make sure you don't get a 2 way.

[ramm]

Differential Options:

Well, im getting close to that time where i need to make my decision on which differential to go with. Like i stated before, this will be driven on the street and also on the track (mainly HPDE's). My options are: J30 VLSD Nismo 1.5 way ( i get a decent discount at a Nissan dealer) is the 1.5 way really worth it or no? anyone have experience? Also i found a 93 VLSD from a J30, so i guess i'll need to grab the axles also. Right? i have a 95 se btw. Thanks

[spool_sample]

S15 Helical. To me, helicals feel like a 1.5-way but without the harshness or constant maintenance.

[veilside180sx]

S15 Helical. To me, helicals feel like a 1.5-way but without the harshness or constant maintenance.

i concur, but a clutch if setup right...isn't too bad. Most have them set up to aggressive for road course duty imo.

[AceInHole]

If you can set your car up well enough, the helical does a great job. On the other hand, if you're band-aiding the issue of an unloaded inside rear with a clutch diff, I can't imagine the diff lasting very long. I've known of a couple guys who've blown up clutch diffs in high traction/ high power applications.

[ramm]

I've been doing alot of research on this also, it is obvious that the Helical is the suggested LSD for my needs. Now i have to find one! Thanks guys, i think this board is really progressing...

[McCoy]

I remember doing a fair bit of research before making my purchase. I picked up an S15 HLSD and the output shafts while I was in Japan earlier this year. No reviews yet since it's still sitting on the shelf in my garage. All that I do know is that with a T28 at 10psi and an open diff makes for a fun day at the track : -)

[AceInHole]

I'm running an OBX HLSD. Seems to be holding up fine. I rebuilt mine with McMaster belleville springs when swapping it to the new car, though.

[ramm]

Another question, actually 2? Is it worth it to buy the OBX HLSD and save money over the HLSD? Or Just buy a VLSD? Also can you run R-Comps effectively with these differentials?

[AceInHole]

The VLSD was woefully inadequate for R-comps at/ near the limit. The HLSD and some suspension tweaks to get more rear bias helped enormously. I've been happy with the OBX LSD. It seems as effective, if not better, than the S15 diff. I'd recommend re-packing it with better bellevilles before installing it, though.

[ecugrad]

The VLSD was woefully inadequate for R-comps at/ near the limit. The HLSD and some suspension tweaks to get more rear bias helped enormously. I've been happy with the OBX LSD. It seems as effective, if not better, than the S15 diff. I'd recommend re-packing it with better bellevilles before installing it, though.

What diff housing did you put the OBX in?

[ramm]

AceInHole Where did you source your OBX HLSD from, how much? And how much for the McMaster bellevilles? this is probably going to be my next mod and i would like to do as much research as possible. Also this will be going into an S14 open diff...

[AceInHole]

I got my diff through my friend's shop straight from OBX, I think. They're on EBay all the time, though. The McMaster part number I used was: 9712K83 Type Belleville Disc Springs Material Steel Steel Type Grade 1074 High-Carbon Steel Minimum Inside Diameter .630" Maximum Outside Diameter 1.250" Thickness .062" Overall Height .092" Load 480 lbs. Deflection at Load .015" Flat Load 870 lbs. Specifications Met Not Rated I preloaded it REALLY tight, although the most important part is the case can still fully close (took a lot of trial and error).

[turtl631]

Oh cool, so using those springs allowed you to get some preload a la that Quaiffe that's not available for the 240SX that comes with some preload? Does this avoid total loss of torque transfer if you lift a tire?

[mmdb]

Another question, actually 2? Is it worth it to buy the OBX HLSD and save money over the HLSD? Or Just buy a VLSD? Also can you run R-Comps effectively with these differentials?

I'd have to say no. S15 HLSD was a direct drop in. I then had it checked at the local differential shop and it all came back within spec. I'd say it's definitely worth it knowing you have an oem piece in your car. Prices on s15s have rather dropped. You can find one on ebay for ~500 dollars with axles. It's not so much more than other brands such as OBX, but like I said it's proven. There's no reason why you can't run with a VLSD, but will it hold up? That'll always be a question in the back of your mind. I'd say do it once and get it over with - go HLSD.