letitsnow Posted June 3, 2012 Share Posted June 3, 2012 I am in desperate need of an LSD. I currently make about 270rwhp and 340ftlbs of torque, I'm planning on another 100ish hp in the future and would like to account for that. The car is primarily a street car and autocrosser with some trips to the drag strip. You guys that went with the OBX unit, are you happy with it? Would you buy another one? Any issues? I figure that my other options are an aftermarket 240sx 1.5 way, like a KAAZ or Carbonetic. A used 240sx 2 way can be had cheap from the drift crowd. An STi r180, but that might not be the greatest with my planned power increases. I suppose the z31 is on the table but they generally have a bunch of miles for what they cost. I don't think a Quaife is in the budget, a new 240sx clutch diff is pushing it. Quote Link to comment Share on other sites More sharing options...
akeboshi Posted June 4, 2012 Share Posted June 4, 2012 Ive got a fresh r200 with an obx installed by me going in the car this week. Ill let you know how I like it. Quote Link to comment Share on other sites More sharing options...
duragg Posted June 4, 2012 Share Posted June 4, 2012 I've got 200 rwhp and I really like my R200clsd. Shimmed the clutches and would shim more if I ever have the energy. Its a blast. "Power steering". How did I ever drive without it. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted June 7, 2012 Author Share Posted June 7, 2012 Is the shimmed z31 diff still smooth or is it clunky like some of the aftermarket units? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted June 8, 2012 Share Posted June 8, 2012 I like it. No issues. Just two black strips on the pavement, no ill handling, and some cash left in my pocket to spend elsewhere on the car. I would buy it again. Quote Link to comment Share on other sites More sharing options...
EMWHYR0HEN Posted June 8, 2012 Share Posted June 8, 2012 No issues in 2+ years now. I would buy another unit. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted June 8, 2012 Share Posted June 8, 2012 I've done the shim upgrade to a Z31 CLSD. I would probably just install it and not do the shimming if I had it to do over again. I had lots of chatter trouble until I added a total of 3 tubes of friction modifier. It is great now. No ill behavior. Quote Link to comment Share on other sites More sharing options...
duragg Posted June 8, 2012 Share Posted June 8, 2012 No chatter, added 1 or 2 shots of juice. Not sure I could hear it over the howl of that stupid solid diff mount and trashed companion/stub joints I have. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted June 8, 2012 Share Posted June 8, 2012 duragg-thanks for all your advice when I was putting that diff together. It is sweet now. When it was locking - it was like all hell was breaking loose. You'd have not only heard it but also felt it if you had "chatter." It had the feeling of a loose wheel or a flat tire. All good now, but diff is leaking fluid either from a fill plug, the vent, or the cover gasket (new and carefully installed). I was careful not to overfill. Just enough leak to slime the bottom of the diff cover, but not enough to drip, yet. Gonna clean it up real good and shake baby powder all over it to try to find location of leak. I don't want to oil the track and be the cause of a guardrail close encounter. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted June 8, 2012 Share Posted June 8, 2012 Is the shimmed z31 diff still smooth or is it clunky like some of the aftermarket units? There are two different things going on here: adding clutches to a 300ZXT diff, and shimming. Adding clutches will allow the CLSD to hold down more power and also make it more aggressive. Shimming makes the breakaway torque tighter. Adding the clutches is a very good idea. Shimming is probably not necessary for most people and will make the diff more likely to chatter. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted June 12, 2012 Share Posted June 12, 2012 I concur with JMortensen above. My car now makes two beautiful burn-out marks exactly the same length whether I am going straight or in a circle. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted June 12, 2012 Author Share Posted June 12, 2012 Won't adding clutches also increase the breakaway torque? I'll keep my eye out for a z31 diff I think, if I can't find a reasonable one, I guess I'll go with the obx. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted June 12, 2012 Share Posted June 12, 2012 Won't adding clutches also increase the breakaway torque? I'll keep my eye out for a z31 diff I think, if I can't find a reasonable one, I guess I'll go with the obx. Yes. The issue is that on the Z31 they ran one clutch per side to drive the axle and then put a big spacer in there to take up the room where the other two clutches should be. If you put too much power to it you'll strip the clutch. By replacing the spacer with the two clutches you will make the diff more aggressive and increase the breakaway torque, but it's really necessary to hold down a lot of power. If you get the NISMO diff or one out of a Skyline they don't have the spacer, so no clutches needed. The Skyline diffs are more aggressive than the Z31 with the clutch upgrade, so you're still not going too crazy with the Z31 upgrade. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted June 18, 2012 Author Share Posted June 18, 2012 You guys with the OBX, what are you using your cars for typically? Quote Link to comment Share on other sites More sharing options...
akeboshi Posted June 18, 2012 Share Posted June 18, 2012 I installed my obx the other day and it drives like I never did anything.... till I do a burn out!!!! It feels very stable but I havent done any serious cornering on it yet. Still shaking the car down. I plan on autocrossing it but it would be nice to have a 1.5 or 2 way if feasible. For me though , the obx was the cheapest. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted June 21, 2012 Author Share Posted June 21, 2012 Think a 200k mile z31 diff is worth $650? Seems like a lot of miles. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted June 21, 2012 Share Posted June 21, 2012 Yes, but opinions vary. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted June 22, 2012 Author Share Posted June 22, 2012 If I might ask, why so much for a likely worn out factory diff when a low mileage used aftermarket diff is the same or just a touch more. If I understand correctly, any aftermarket diff for a 240sx that originally had an open diff will work, right? Quote Link to comment Share on other sites More sharing options...
letitsnow Posted June 29, 2012 Author Share Posted June 29, 2012 Am I missing something obvious where the z31 diff is better at something than the aftermarket units? My experience is limited to factory units on other cars I've messed with, never aftermarket diffs, so I very well might be missing something silly. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted June 29, 2012 Share Posted June 29, 2012 (edited) More aggressive than the helicals and can be shimmed tighter if necessary. On a helical you get what you get, unless you have different pitch helical gears that you can swap out. The aftermarket CLSDs offer the most traction. OS Giken, KAAZ, etc, but the price is high. Edited June 29, 2012 by JMortensen Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.