You don't have to pull the axles off, but you have to unbolt them and drop the rear sub-frame.

Welded is only good if your running low on funds. Works well but will destroy your tires much quicker. More issues come up as you get better and eventually you will want something better. But if you just drift sometimes for fun it works great.

I would say the clutch Lsd will be better. Granted you have to find one in good shape or rebuild one so that gets frustrating and much more expensive. It would be better then the welded though since you drive your car on the street. It's a good LSD if you have on in good shape. It locks right up. Though I’ve never seen a rx7 with a welded, since our cars come with LSD or they can be swapped in.

Viscous, is kinda tricky. Better then open but that's about it. It's not that there is something wrong with it, it's just the way it works. It might or might not lock. We don't want that for any type of racing. But it can be done.

Then of course there are after market LSD's. Cost a lot more but coming from anything else you will love it. 2-way if your just gonna drift, 1.5 if you wanna do grip and drift.

 

biddy bump

 

well IMO the V lsd for the FC is a little less predictable and the C lsd gets hot and starts acting like an open diff after a short while.

 

the VLSD just sucks, plain and simple, for drifting.

Get a clutch-type LSD from the S4's, a KAAZ 1.5 or 2 way or some other hard locking diff. Leave the Torsens to the road racers.

 

welded diffs are streetable not a lot of fun though for grip. they are not predicable like 2 way would be. i have a buddy who drifts his s13 n he says the 2way is way more predicable in ever situation.

welding the diff requires welding the spider gears, its like having a 2way but locked all the time it is giving both axels the same ratio 100 percent of the time. if you read up on who an lsd works n how the internals of the rear end work it will make sense to you after some after thought and minor explaining.

s5 diffs are viscous, they are also more prone do breakage. the pumkin is not as strong as the s4 clutch type which is cast steel or iron idk. but also a draw back to viscous is that it is non rebuildable, it does give the widest amount of drivability but it is only serciable meaning that only the silicon fluid in the diff can be partialy replaced which i believe is all that makes the viscous type lock.

aftermarket clutch type is the way to go, easily rebuildable for cheap, predictable and gives a lot of confidence. clutch type is different in the fact that its engadgement in much greater and stronger. with a clutch type it takes a certain torque to lock the opposing spider gear which can be tunable on certain diffs. the diff itself that is. there is also another type of lsd that is a gear type, cusco makes it and what it does is actually locks the inner tire at a certain torque. not like the clutch type. when it locks it i mean it stops the inner tire from moving, locks it in place and drags it. i dont know anyone who likes this type of lsd.

long story short 2 way s4 clutch type ftw, brand is up to you. some are stronger some are weaker, some are easy to rebuild some arent as easy. but s4 for sure because the pumpkin itself is much superior to the s5 or s6, i have heard of many ppl go to an s4 diff in the s5's n s6's. i also belive the 99 spec "s6" (which is really a s8 or s9) is a clutch type that is pretty strong. if u have an fd ive heard of ppl doing ford 8 inch rear ends that are irs in em. i think they use em in formula d but idk i heard it from a dumbass lol so look into it first

 

thanks guys for the input.

 

I have driven only one OEM clutch type mazda unit that worked at all. It was a stock S4 turbo II unit, and it was "barely" enough to engage both tires. The rest (about 16) didnt do anything. A welded diff as mentioned is good in a slide, and bad at everything else. Really a Kaaz is the only diff I run, as its predicable, and can be used on a road race track, street, drag, and drift. Dont settle for half-***.

 

my fc has welded rear end. its about a trillion times better than the worn out stock lsd that was in there.. well actually its the same rear end. its totally fine on the street, never had a problem with it and its amazing for the dori. sucks when your car dies and you have to push it around a corner though. takes at least 2 strong guys to push it. gotta overcome the grip of the inner tire. something to watch out for. but the only real bad effect on the street is the squeeling and sometimes hopping of the inside tire around slow turns. dont even bother with viscous. either weld your diff buy a 2way or rebuild the stocker.

 

I always hear people say that welding the diff will wear the tires faster and though that is true, the whole reason for welding it is so you CAN wear the tires faster (drifting) so I don't get why everyone brings that up.

 

most peoples drift cars are also their daily driver... that is what they are talking about with worn tires....... for daily driving..... i cant believe i had to just explain that to you................

 

Welding a lsd is like taking the perfectly good air out of your tires and replacing it with water. I mean sure its full but at what cost?
I've personaly never seen a welded diff on a daily driver that didnt break or break something else. Its fine if your in an offroad jeep but an FC has lsd options from the factory. Welding is a cheap way to a cheap result.

 

Thanks for that.
I meant that if you welded the diff on your DD drift car then you obviously have already come to terms with the fact that you are gonna go through alot of tires so it shouldn't be a concern.

 

heres my run down of the whole thing. i started out with the LSD in my S$ loved it but eventually it blew out. when that happened i welded my diff. BIG mistake. going around a corner I had bad wheel hop and it would want to turn wide. (Understeer.) And if going above 70 and though a turn it would shimmy and feel like it was gonna kick out. i wish i had just done it right the first time and bought either another S4 LSD or a KAAz 2 way. if your gonna go after market go 2 way helical viscous is crap for drifting pure and simple. this can be seen as hearsay or blown off but its just my .02.

 

hmmm, I can't decide what I should do...
I do grip driving most of the time, but in some slower corners I want to drift, or when I see a nice empty parking lot,
..but I don't want that strange D1 style drifts with way too much angle anyways ...I just like that beautiful keiichi tsuchiya drift-grip-mix style
And when it rains it's like a drift training for me, because I hate grip driving with no grip.

I have a S4 TII with 87000miles on it, so I guess the stock clutch type lsd is worn out.
I was thinking about buying a Torsen Diff from a FD,
a 1.5way LSD would be perfect for what I want to do I guess, but I think that's overkill, and expensive...I just want to have fun when grip driving on mountain roads and be able to drift if I want to too.
Are there still rebuild kits for the stock s4 clutch type lsd? If so, where? and how much $?
so what do you think is the best choice for me...stock LSD rebuild, 1.5way or torsen.

 

You could always buy an open diff and weld it and then keep the stock LSD and swap out to see what you like better.

 

I welded my diff once and hated it. wen I was drifting on a road course it would under steer to much before I would start the drift.

Now I run a shimmed turbo 2 diff , works great.

 

O ya Viscous diffs suck ***

 

do you have to drop the subframe? im in the middle of pulling my diff to weld it. i have the exhaust off, half shafts unbolted, driveshaft unbolted, sublink unbolted, but am having a hell of a time getting to the front mounting nuts on the cradle. i was pulling the 3 nuts that are arranged diagonally from eachother, but was told i can remove the two that are side by side and it'll come out? anyways, is it possible to do without dropping the subframe?
thanks.

 

how do you shim the t2 diff? Do you mean to space the diff closer to the drive gear in the differential case? so theres less gap in between the gears teeths?

 

Ring & pinion? NO,
To shim the diff to lock harder you need to insert a shim in between the clutch plates
Mazdatrix sells thicker clutch plates to do the same thing. But shimming is much cheaper.

I do this at my shop a lot. I charge $250 for every thing.
If your going to do it your self you will need to pull the diff out.
Mark the ring gear placement then pull it off and separate the clutch pack. Come up with a shim that is the same shape as the clutch disc. I prefer to use two, one on each side of the packs.
the tough part is putting it all pack to gather correctly.
Put the ring gear back on your mark.
then when you put it back in the case you need to set the lash (Ring & pinion)

If you don't know what I'm talking about I don't rec amend that you do it your self.

 

I get it now. thanks. Im also running the t2 diff, But i wish it would lock harder, so Ill try this. Itll be cheaper than buying a tomei or kaaz 2way diff..

 

call me at my shop if you need more info.
818-768-5132
dynamictuning just ask for me

 

Welded is NOT dangerous on the street. I run a welded DAILY and all this bs about "oh it understeers, in the rain you can't control it etc" is exactly that. BS. It's all dependant on your suspension and car. In theory, if you have ******* slicks on the back and **** tiny wheels on the front with a welded, it will push you around turns and you will undersreer. But if your that dumb to run it like that then you deserve to understeer into a wall. The only time you will notice it's even welded is sharp turns in parking lots due to it wheel hopping. I've driven my welded bmw as a daily for over a year now and I can talk from actual experience.

 

It's only true because when you turn with a normal open or lsd diff, both back wheels turn at different rates. But with a welded you turn and they both turn at same time (reason for why welded's wheel hop) and thus your wheels hopping in turns slightly, wears out the tires prematurely.

 

With normal, controlled driving, not much is considered dangerous, short of broken axles or wheels falling off.

I guess it's the times when you run spirited on the street, but unexpectedly traffic comes out. I wouldn't want to have a welded diff there. Plus I can't stand understeer or wearing tires faster.

But that's just me.