luseboy Posted February 19, 2012 Share Posted February 19, 2012 Hey, So I'm about to go and work on my car again for the first time in a couple weeks (ansy to start working again!), and the next big thing is removing/rebuilding all of my rear suspension/driveline. I don't know what condition my diff is in, or what it is. I believe it to be the stock R180 that came on a '73 240z in california (any ideas?). It does appear to have the stock half shafts. I want to upgrade to an lsd eventually, but it is an expense I will have to spare for now. A friend of mine (a drifter) recently welded the diff on his miata, and this got me thinking... maybe I should just weld my diff for now, and then upgrade to the lsd later on. No, I am not a drifter, and I don't plan to really 'drift' in my s30. I like to 'grip' though on occasion I will wag my tail just a little bit. What is the downside to a welded diff versus an open diff? I know it won't be as good as an LSD, and I know it has the potential to blow up, but is it worse for 'grip' handling than an open diff? Seems to me that it could be pretty bad, considering both rear wheels would always want to be going the same speed... But maybe it'd acctually be good? I guess this is just a thread questioning whether or not this would be good or not. I am sure Jmorteson and JohnC have some very valuable input here. Again, I am not asking if a welded diff is a good substitute for an LSD, but rather, if it would be better or worse than an open diff from a handling, driving spirited on the backroads perspective. Thanks, Austin Quote Link to comment Share on other sites More sharing options...
JMortensen Posted February 19, 2012 Share Posted February 19, 2012 There are handling issues to be dealt with, increased understeer and oversteer among them, those can be dealt with. There isn't too much controversy over whether welded is faster than an open diff. It is. The real problem with a welded diff on the street is that it isn't very safe. Then again, "spirited" driving in canyons isn't safe either, take it from someone who has literally been over the edge. Locking the rear wheels together is a reasonable enough thing to do when it is dry, but when you have hi performance tires on your car and it's raining and you get off the freeway onto a decreasing radius offramp, or when you crest that hill at the edge and realize that there is a wet sharp turn just on the other side, that's when it gets sketchy. I've known people that commuted daily with spooled trucks to work in the rain/snow/ice of Seattle, so it can be done, but it's a lot more dangerous IMO than having an open diff in those situations. I wouldn't use a welded or spooled diff on the street. I'd save up for the LSD. Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted February 19, 2012 Share Posted February 19, 2012 Another valid point is the amount of stress on the welds. If it decides to unweld itself when your going 70mph on the freeway, your diff will lock up and you better start praying Quote Link to comment Share on other sites More sharing options...
Nelsonian Posted February 19, 2012 Share Posted February 19, 2012 Keep it open for now, save and then get an lsd. ^^^ Been in a very simular situation before in a friends old toyota 4x4 wagon many years ago. In hind sight, making the trek from NC, to Florida for Christmas break/surf trip on a shoe string budget and with bad rear bearings was not the brightest idea. I got to see the sparks flying from the bottom of the car in the back right pass seat as the right axle still connected with wheel went rolling off into the woods, still glowing red. Stranded in Bruinswick Georgia for a couple of days, ah yes the memories. Quote Link to comment Share on other sites More sharing options...
stprasinz Posted February 19, 2012 Share Posted February 19, 2012 (edited) If you go to an intersection, you would either chatter, or slide in a welded. Neither a good thing if you are trying to grip drive. And thats slow speed driving, add more speed undoubtably slideing, and slideing and grip are totally different animals. I agree with the stay open, save for lsd. Edited February 19, 2012 by stprasinz Quote Link to comment Share on other sites More sharing options...
ckrell Posted February 19, 2012 Share Posted February 19, 2012 (edited) I'm going welded (done it before) its not as safe as open but to each his own comfort zone. Edited February 19, 2012 by ckrell Quote Link to comment Share on other sites More sharing options...
luseboy Posted February 20, 2012 Author Share Posted February 20, 2012 I didn't know welded was acctually faster. I guess it makes sense, it lets you put more power down than an open diff. I have spun on the canyons once (very sobering experience) and would have gone over the edge if the car had moved down the hill another 3 inches (literaly the front right of my bumper hit a gaurd rail 3 inches before the end of the gaurd rail). However this was about 4 months after I got my first car (well my current car still, hopefully not for much longer). I can visualize how a welded diff would make certain sketchy situations much more sketchy, that makes sense now. And an LSD is safer because it acts more like an open diff when you're not driving spirited-ley, right? I guess that makes perfect sense. I think you all are right, for now I'll learn to drive the Z with an open diff (wouldn't want to ruin it before I even really got to know it well), then I'll get an LSD later on like I had planned anyways. I guess I am still a sorta new driver (had my license 2 years), so I should stick with the open diff, considering I won't be used to the Z for a while anyways (or RWD). I guess the only other question is, would a welded diff be considerably more fun? I'm not planning on tracking the car or anything, just want a fun semi-DD/canyon carver/auto-x once in a blue moon. Thanks for the responses guys! Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted February 20, 2012 Share Posted February 20, 2012 I have never driven a car with a welded diff, and I have never even had a ride in a car with one. Even though this is true, I feel that is because anybody who has performance in mind avoids a welded diff. Welding your differential is done for drifting, that is all. It is one of the cheapest ways to drift. Quote Link to comment Share on other sites More sharing options...
johnc Posted February 20, 2012 Share Posted February 20, 2012 I have never driven a car with a welded diff, and I have never even had a ride in a car with one. Even though this is true, I feel that is because anybody who has performance in mind avoids a welded diff. Welding your differential is done for drifting, that is all. It is one of the cheapest ways to drift. Damn, I guess my years of road racing an ITS 240Z with a welded diff in my 240Z was actually drifting. Whoda thunk it! Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted February 20, 2012 Share Posted February 20, 2012 Damn, I guess my years of road racing an ITS 240Z with a welded diff in my 240Z was actually drifting. Whoda thunk it! I said that I feel and also stated that I had never had a welded diff. I was stating my assumptions. I never said that anything I said was factual or to be the truth. Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted February 20, 2012 Share Posted February 20, 2012 I have never driven a car with a welded diff, and I have never even had a ride in a car with one. Even though this is true, I feel that is because anybody who has performance in mind avoids a welded diff. Welding your differential is done for drifting, that is all. It is one of the cheapest ways to drift. Incorrect. It's not a Z, but in warm weather I daily drive my '79 malibu with a spool (which is the same as a welded diff [locked axles]). "Timestamp" is just incorrect. It's not only done to drift. Like you say, its a cheap alternative to an LSD. I avoid driving in the rain, and SHARP corners like in a fuel station are annoying, and squeaky, but it's not the end of the world. I cannot speak from experience on the strength issue, but I can tell that on the street its FAR less dangerous than people make it out to be. Many many people speak from absolutely zero first hand expirence, like "timestamp", but rather word of mouth, and 'stories' they heard. Quote Link to comment Share on other sites More sharing options...
Leon Posted February 20, 2012 Share Posted February 20, 2012 I said that I feel and also stated that I had never had a welded diff. I was stating my assumptions. I never said that anything I said was factual or to be the truth. Then why say it at all, Jon Kyl? http://www.colbertnation.com/the-colbert-report-videos/381282/april-11-2011/pap-smears-at-walgreens Quote Link to comment Share on other sites More sharing options...
seattlejester Posted February 21, 2012 Share Posted February 21, 2012 To cut down on the danger factor you can install a rear proportioning valve and cut down on the line pressure when it's raining, making the car brake more with the front making the locked rear less of a problem. A local friend does this, and he's also been dailying his car for 3 years or so in seattle weather. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted February 21, 2012 Share Posted February 21, 2012 To cut down on the danger factor you can install a rear proportioning valve and cut down on the line pressure when it's raining, making the car brake more with the front making the locked rear less of a problem. A local friend does this, and he's also been dailying his car for 3 years or so in seattle weather. Does this really cut down danger though? Normally you can crank in more rear brakes when it is raining because you don't have the weight transfer in the wet. So compared to an open diff, you now have greater stopping distances and sketchier handling, because the wheels are still locked together so one of them is going to be sliding when you're cornering. Quote Link to comment Share on other sites More sharing options...
luseboy Posted February 21, 2012 Author Share Posted February 21, 2012 I already have a wilwood prop. valve waiting to be installed. I'm still debating on whether or not I want to weld my diff. I guess I'll wait till I get it out of the car and everything. Who knows, maybe I'll pull it out and it'll be an LSD. That'd be very cool! Maybe I will weld, maybe I won't... Is it gonna add anything to the fun factor? That's what I'm really about... Quote Link to comment Share on other sites More sharing options...
Leon Posted February 21, 2012 Share Posted February 21, 2012 This is going to be a street car, so I'd wait for an LSD. I'm thinking of the fun/(inconvenience+danger) factor. You're not going to enjoy making tight turns with a welded diff, and there are the aforementioned safety concerns about using it on the street. Get the car driveable and then worry about open vs LSD. A diff is not difficult to change, especially after the work you're putting into that car. An open diff is far from a deal-breaker when talking about Z-cars and fun! As JM mentions, you need more rear brake in the rain. Dialing it down is just making it more dangerous. Quote Link to comment Share on other sites More sharing options...
johnc Posted February 21, 2012 Share Posted February 21, 2012 Maybe I'm weird... I drove on the street with a welded diff for a couple years. Granted, it was in SoCal but many times I would drive to or from an autocross in the rain in my welded diff 240Z towing a tire trailer and never once felt in any danger. Even at the "Deluge" (the 1997 San Diego National Tour) where a huge puddle on course ripped off my front spoiler I never felt the car was out of control during the competition or driving home in the dark, in the rain for two hours. Quote Link to comment Share on other sites More sharing options...
luseboy Posted February 21, 2012 Author Share Posted February 21, 2012 Leon, you're probably right haha. I guess in the end, I wouldn't want to lose all my hard work to one stupid mistake in the rain. I'm not saying a welded diff is gonna be the root cause, but it certainly wouldn't help. I mean in the end, this will be the first RWD car I've driven, the first car with excessive upgrades, the lightest car, the oldest car, the most powerful car, etc. etc. etc. So having a welded diff on top of that probably won't help. John I imagine you have a **** ton more driving experience than me, especially with Z's. Maybe I'll leave it open for now, and then weld it later on while I'm saving up for an LSD. Idk, like I said, it's still in the car. Gotta paint my engine bay, undercoat my front wheel wells, and put in my front suspension before I can get to the rear end. At this point, I'll probably just use the open diff for a while, then upgrade to some sort of LSD with CV's. We'll see what happens, but that's what I'm thinking at this point. Is there any real benefit of the R200 LSD out of a 300zx vs. the R180 out of the STi? is a CV axle conversion worth it? Quote Link to comment Share on other sites More sharing options...
luseboy Posted February 21, 2012 Author Share Posted February 21, 2012 What I should really do is get a phantom grip! Don't worry, I'm kidding. Quote Link to comment Share on other sites More sharing options...
TheMission Posted February 21, 2012 Share Posted February 21, 2012 I'm in the same boat with upgrading my rear diff to handle more power, but decided that it wasn't technically too difficult to drop it and weld it up later, so I left it and will let the open diff go until I want more grip and just do the work later. I want the R180 from the subaru for one reason- Bolts right in. With the Axles, it's pretty much plug and play, as well as running easy and available options for ratios and types of lsds I could run a R200, but then I need the mustache bar and other mounts as well as probably wanting to upgrade the axles anyways.... It'd be cheaper I guess, but new axles and a "newer" lsd seem like a better option if I want to run something other than a welded diff. 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.