The Central Hub for DSM Community and Information

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. This is where the DSM platform history is documented and archived. Log in to help us in our mission, and to remove most ads from the browsing experience.

Welded Center Diff as a Daily Driver?

Which should I get? Don't vote if you don't know.


  • Total voters
    104

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

96whgsx

15+ Year Contributor
745
6
Sep 28, 2004
San Francisco, California
I'm about to send my car in for a 6 bolt swap very soon and while the tranny is out, I would like to beef up the center diff a bit. I was thinking of either a welded center diff or the speed design 4 gear spider diff. I would ordinarily jump on the 4 gear option but it would cost at least 500 bucks. So, looking at value, I was thinking of the welded center diff. I read through the posts of popping noises with tire chirpings at low speeds combined with sharp turns. I am also worried about the rear axles and the overall stress on the drivetrain. I will mostly do city driving, rarely highway.

Another queston: If I chose to get the 4 spider gear diff, and lets say something in my transmission goes out, would the center diff still be good or would it be damaged as well? I have a feeling that something may happen to the tranny, it makes a loud whirring sound 3-5th gears, the higher the gears, the louder it gets. It will stop making noise when the throttle is light enough to the point where I don't put load on the motor.

My plans for the future in terms of mods are 14b with supporting mods and then upgrade to a 50 trim or bigger.

Sorry if this is unorganized. BTW, I already searched but didn't get a straight answer, some people liked it, others didn't.
 
I'm getting mine welded soon, and the car rarely sees the highway.

The only downfall is a slight reduction in turning radius, the skipping rear tires, and some claim added stress on the drivetrain.

But then again, the people who claim that are probably beating the piss out of it. There's enough people who drive them daily that I'm not worried about it.
 
I would say the 4 spider if you are really worried about it. I know from pushing Darryl Hudsons car around the pits that the turning radius sucks with the welded center diff.
 
I got mine welded when it was rebuilt... I haven't really driven it that much, but when I first drove it I hated it. Pulling into parking spaces sucked, but now that I'm used to it I make wider turns and expect to hear it pop. Its just one of those things you need to do and deal with to keep your car reliable, though I am worried about the wheel bearings being toasted.

If you think your tranny might be on its way out now, you might want to wait and get it all done at once. I would have gone with the 4 spider, but the place rebuilding mine told me its not worth the extra money and it could still break. If it broke, it would most likely take out my entire tranny that was just rebuilt.

Anyways, If your 100% sure you are going to be going with a 50 trim, and this is something you want, then weld it. But don't do it until you are certain its where your going, because welding it on a near stock car will make you hate driving it.

Are you going to launch it much? Cause thats the only thing your going to need a beefed up center for. And if you are, then I'd say weld it, so you know you have no weak spots in your tranny.

Just my .02
 
Wow the turning radius can get worse WTF It's already worse then an Explorer or Suburban stock...
 
I love the spool in my car. I think people complain too much about having a welded diff. So what the car hops a little sometimes when making tight turns. Ya, you may have to spend an extra 10 secs parking but, man darn. that 10 secs is going to make a difference. Eventually youll leanr to hold the hweel tighter when turning and it will make sharp turns, just hops a little.
 
How is that hopping for longevity?
I mean, obviously it's not going to make it last longer, but do people with welded centers blow a lot more rear CVs, and pinion gears and such?
 
beat90tsi said:
How is that hopping for longevity?
I mean, obviously it's not going to make it last longer, but do people with welded centers blow a lot more rear CVs, and pinion gears and such?

Only if you're an idiot. Just take your time and don't force things constantly :thumb:
 
My center diff welded itself. I would get the 4 spider option instead of the welded. I've been driving it for a year, and I really am not a fan of it. I mostly do city driving, and its a pain in the ass.
 
On my last 1G the tranny went out. The new on that i had already had a welded center diff. It took some gettin used to but i loved it. Where would you take somethin like that to have it done and what woud it cost? Im thinkin about doing it again. Anybody have any pics of it before and after?
 
I have a spool in my rebuilt tranny and I love it. My car is pretty close to stock and I love the spool. The tire skips when I have to make tight turns but its not a big deal. I didn't really notice a big difference in turn radius because the turn radius in these cars suck. I would recommend you do this.
 
Yeah I would recommend the spool if you want to lock it up. I have it and it's great for traction. While I was in there I put a phantom grip in as well. I didn't notice a difference with that, prolly a waste of money.
 
Did anybody with 2gs have a problem with broken axles when using the welded center diff?
 
http://www.dsmtuners.com/forums/showthread.php?t=173481

I've daily driven, autocrossed, and drag raced on my welded diff for over 5 years now with no problems.

Besides giving you a better launch, a welded diff will elimintae the thrust washers that inherently go bad and fubar the output shaft and x-fer case. I went through two of each before I decided to weld it and eliminate the problem. I think a 4 pinion diff still needs those thrust washers.

My tires don't skip. Why? Because I run sticky Azenis tires on the street and their grip is more than the torque required to differentiate the rear LSD, so the axles spin at different speeds like their supposed to. With my little street tires the inside tire would skip rather than differentiate the rear axles. This does not cause any more stress or wear on the axles or bearings.

For the money you can't beat it.

Rick - '91 GSX :dsm:
 
You can take my advice or not, but I would go with a 4 spider over the welded diff. My reasoning is that I did have a center spool(virtually the same as the welded diff) and traction was great. One day, I pulled into a parking spot and my driveshaft took a shit. It wasnt the shaft but the slipyoke(yoke that goes to the tc)) decided to twist. I pulled the yoke to find the splines inside decided to twist one full turn so I decided the spol wasnt for me. I did swap back to a stock diff for street driving and a vc eliminator for track use and I am happy. Keep the launches to a non agressive form(slip the clutch) and the stock vc and diff will last quite some time. If you want other parts to live, keep the drivetrain reasonbly soft with some give. The welded diff wont give you that.
 
I have a TRE tranny with a spool and no P/S. The car just wants to go straight I tell you. When I'm at the strip it shoots straight with not the tiniest bit of torque steer. For me turning more that 20* definitly requires some muscle and tight turns require both hands. You also want to check your tires pressure more often as it really does effect your gas miliage since if your really low in the front the rear will turn slightly slower than the fronts.

The skipping and poping does take some getting used to. You just will learn to take wider turns as mentioned before and you might end up doing more 3 point turns than you ever thought you even would in your LIFE. You will also want to ensure your carrier's are up to par as the spool/welded CD will help destroy worn out units due to the loads durning turning. Mine where almost like new and I also siliconed them up for extra insurance. So my vote is go ahead with it and don't look back. But don't take your P/S out unless you really like using both hands driving.
 
You could argue theoretically that a welded CD transmits more direct force to the driveline than the VC and stock CD would but it would only be a small percentage. The stock parts don't do THAT much cushioning.

Now consider cars like Hudson's, or any other 10 second car. The vast majority of them still run the stock x-fer case and rear LSD. How much extra stress is 600+ horsepower putting on their stock drivelines? Way more than a welded CD on your street car does and theirs still survives.

My point is the small amount of stress that a welded CD or spool MAY transmit to the driveline is insignificant compared to what big turbos and horsepower does.
the slipyoke(yoke that goes to the tc)) decided to twist. I pulled the yoke to find the splines inside decided to twist one full turn
That wasn't caused by a welded CD or a spool. If it was, as I said, no one would be able to run the stock parts on a fast car but the vast majority does.

If your spline twist is counterclockwise (looking from the front to the rear) then it was from engine power applied through the yoke to a non moving driveshaft. If the twist is clockwise it was from driveshaft force applied to a non moving x-fer case. That's typical of x-fer case lockup with our DSMs. My money would be there.

Rick - '91 GSX :dsm:
 
4pistons said:
You could argue theoretically that a welded CD transmits more direct force to the driveline than the VC and stock CD would but it would only be a small percentage. The stock parts don't do THAT much cushioning.

Now consider cars like Hudson's, or any other 10 second car. The vast majority of them still run the stock x-fer case and rear LSD. How much extra stress is 600+ horsepower putting on their stock drivelines? Way more than a welded CD on your street car does and theirs still survives.

My point is the small amount of stress that a welded CD or spool MAY transmit to the driveline is insignificant compared to what big turbos and horsepower does. That wasn't caused by a welded CD or a spool. If it was, as I said, no one would be able to run the stock parts on a fast car but the vast majority does.

If your spline twist is counterclockwise (looking from the front to the rear) then it was from engine power applied through the yoke to a non moving driveshaft. If the twist is clockwise it was from driveshaft force applied to a non moving x-fer case. That's typical of x-fer case lockup with our DSMs. My money would be there.

Rick - '91 GSX :dsm:

Trust me, my yoke wasnt twisted when I installed it(brand new) along with my spool. After a few miles(maybe 1k) of street driving, parking spaces, and just normal driving all together, I pulled the tc for something or another and noticed that the spines had twisted. Have you ever drive a car with a spool in it? How about making those normal tight left or right turns into parking spaces? Well, I have and I know. The front and rear are locked together with a spool and tight turns puts the drivetrain in a bind and is alot more stressfull on the drivtrain than you think.

And also, my tc hasnt locked up. The car has less than 100k miles and finally started to leak. Instead of me trusting the dealer with my car, I just purchased the yoke, u-joint, and seal and installed them myself.
 
10 to 7 in favor of welding the center diff instead of 4 spyder gear center diff on a STREET CAR? This is precisely why you should NOT poll people for stuff like this! You never know what idiot votes and why he is doing it...

Welded center diff should only be used on dragracing race vehicles, which RARELY see street duty. And certainly NOT on a DAILY DRIVER!
 
Based on what data do you make a statement like that????

Perhaps you didn't read my first post in this thread - "I've daily driven, autocrossed, and drag raced on my welded diff for over 5 years now with no problems." That's my experienceand I've spelled out in many places on this board how a welded CD works for me. I know two other local DSM's with similar experiences.

Show me your data where welded CD's should "rarely see street duty" and give me 5 years of experience to back it up.

I am not an "IDIOT" and don't like the inference, especially from a so-called "Wiseman." Exactly what part of this thread leads you to believe anyone in it is an idiot? There are very balanced discussions for and against with everyone noting their personal experiences.

This is precisely why you should NOT poll people for stuff like this!
Then tell me what the hell this board is for! It's for DSM enthusiasts to exchange help, information, experiences, and ideas, which is exactly what we're doing.

Rick - '91 GSX :dsm:
 
Well I don't care to be called an Idiot for running a CD spool. I'm no expert on DSM's or building cars for that matter. I've built quite a few Rods and like everyone else I've done some pretty stupid things that costed me some hard earned cash, but it's always a learning experience.

If you plan on doing some serious drag racing locking your front and rear axles is very advantagous. I'm pretty sure all those High HP cars are doing the same. I didn't want my front end unloading and possibly loosing power through slightly lifted front wheels. MY car is going to be a drag car in the near future, but until then It's one of my DD.

I would get what you can from this thread and decide if a welded CD or spool is for you. Just know that the center diff's do explode and cause lots of damage when they do. They are one of the weaker links in our drive train. That was one of the reasons for me not kepting mine open. Why I also didn't go with the 4 spider CD. It's stronger but they can still break. I talked to Jon at TRE when I had my tranny done and asked him a ton of questions. He says his tranny's can hold 600+ HP. I plan on putting down 700 w/Nitrous after I finally get my motor done. He pretty much said that it would be in my best intrest to get a spool as to not have to worry about the CD blowing up.

Oh yeah one more thing. It does make AWD donouts a lot easier. Which is very fun.
 
I have been running a spool for about 6 months and I love it. The guy who built my tranny highly recommened it for me since I do a lot of drag racing. I also drive my car daily and never had a problem. He said it is a little harder on the rest of your drivetrain but it is a lot safer for your tranny. What is more expensive to replace an axle or a tranny? Just get a spool or a welded center diff. and you will be happy.
 
Just to give you a bit of background. I have been making and selling VCE’s before there were VCEs… (since late 90’s) and I have been locking my center diff for over 7 years. So I do believe that I have you beat in that regard… And the funny part is that I am usually used DEFENDING locking center diff, but for appropriate duty only!

I know, probably better than most, all the benefits that you gain by locking your center diff (be it through VCE, a spool or a welded center diff).

Let me assure that locking your center diff for AutoX duty is a terrible idea! You say that you “autocrossed”. What does it entail? Once/twice a year, or actually following a series for year after year?

Well, I have done it on a pretty competitive level for many, many years (some as much as 10-15 events/year) and I am guessing that you weren’t very competitive in your class… And if you were doing well, that ether shows at lack of competition in your area, or, you are a brilliant driver who can do MUCH better without a locked center diff.

A locked center diff completely throws off the balance of the car during extreme cornering. It causes even worse understeer going into corner and oversteer coming out of the corner. The oversteer can be beneficial under some conditions, but understeer is terrible and has no redeeming quality in racing. If your “years of autoxing” didn’t make you realize this, I am pretty sure that this rules out a “brilliant driver” scenario I proposed above. BTW, the photo in your profile shows extreme case of understeer, not to mention a suspension that is too soft…

Lastly, why would you ever lock your center diff on a 13 sec car? A 13 sec car is certainly capable of destroying your stock center diff (especially with a strong clutch), but that is a reason to get a 4 spider gear upgrade and NOT weld your center diff or use a spool. A 13 sec car does not have enough power to have major improvement in the launch, so it is pretty much wasted on the drag strip. IMO, it should not be used unless you are running at least 11's.

It is nice to demand “data” behind my claims, but we both know very well that no one has done a controlled study to create such data. So without it people must rely on experiences and opinions of others. And it is my advise that people carefully consider the source of such information.

As for my personal set-up, I have been running Speed Design center diff since ’98. I soon started locking it with my VCE (made from cut down VCs) for drag racing and FWD dyno duty. But I did my share of street driving with VCE (when I was too lazy to swap in a VC). And I hated every moment of it when I had to turn.

This past year, I made in excess of 600whp and never had a problem with this combination.
 
i'm debating on what i wanna go with on my setup as well. but don't really know ALL the lil in's and out's of each and what each one does exactly or why i should choose one over the other. was hoping someone could maybe elaborate on this and when you'd use each one. listening to half the people saying "the spool is great and i like it, so choose this," or, "go with the welded diff," doesn't really help much. how bout ya'll tell us why you'd choose one over the other and educate us instead of the bickering? what is each one designed to do? the "supposed" advantages and disadvantages of each. drag racing, pure street, auto-x, some of this and some of that, etc. of course some of ya'll are more tolerant to a race part on a street driven car than others, but this would help us decide.

spool
welded diff
kazz
quaife
4 spider
VCE

anything else i'm missing? as for me, i'm setting mine up for just drag strip and street. no auto-x but i'll just say i'd like to have all the grip i can while still maintaining some enjoyable street driving around town without it being a friggin pain in my butt.
 
Sorry, I didn’t reply sooner, I was having fun in Ohio :).

Spool, Welded diff VCE:

Are all ways of locking your center diff, turning your car into a “4X4”. This is fine for going straight, off-roading, or driving in snow/wet conditions. It NOT good daily driving, especially if you have good, sticky tires.

Spool is a device which locks the center diff from the inside, it can be reversed. But you usually need a good core center diff to make it work.

Welded Diff is just that, you take your stock front diff and weld it. It is irreversible (duh), but you can take blown center diff and weld it, so you wouldn’t be ruining anything valuable.

VCE locks the center diff from the outside. Its main advantage is the fact that you can remove it and turn your car into AWD, in less than 25min (about 1/3rd the time it takes to remove the Spool or Welded center diff). So it is a preferable option if you are planning on going back and forth fairly often. VCE’s weak point is the fact that you are still relying on a stock center diff and its two spider gears, so those can still fail. For ultimate effect, you want to use 4 spider gear center diff and a VCE. But that becomes more expensive…

Kazz, Quaife or Cusco:

All types of limited slip center differentials. They usually offer better limited slip feature, but they are not any stronger than a 4 spider gear center diff.

4 Spider Gears Center diff:

Factory center diff. comes with only two spider gears. It is by far the weakest link on DSM trannies. It is the reason why DSM drivetrains have reputation for being weak. Upgrading the center diff is a MUST on anything running faster than 13 sec (and you can break it even before that point)! The most common upgrade is to convert it to 4 spider gears, cost is usually between $400 and $500. But this does not in any way effect your “limited slip” feature. You still rely on a crappy viscous coupling.

That is all that I can think of at the moment.
 
Add Value - Be Respectful - No Trolling - No Misinformation - Participate Often!
Support Vendors who Support the DSM Community

Build Thread Updates

Latest Classifieds

Back
Top