can you convert an open diff to a lsd?

[call me jack]

Hey, i'll start this off by pointing out that i have not opened up the diff on any e30, yet. So i dont' know what it looks like inside. but i was wondering if you you could take your existing open differential apart, and install a clutch pack made for the lsd differentials?

just wondering, in the event that it could potentially be a little bit more cost effective.

[asubimmer]

yes

[call me jack]

really? is it pretty straight forward? As in, do i just install a clutch pack under the planetary?/ replace planetary with another gear that is set up for a clutch pack underneath?

[Mike The Bavarian]

you're probably better off just buying a lsd.

[crazyman]

really? is it pretty straight forward? As in, do i just install a clutch pack under the planetary?/ replace planetary with another gear that is set up for a clutch pack underneath?

Yeah like he said it would be easier to buy one. I just started looking at junk yards for a totaled BMW with a 4cyl and I found one with LSD. However if you plan to build the engine it be a better idea to find one out of a newer 6cyl, because those ones have medium casings which are better for the higher power.

[call me jack]

See thats the thing; up here in minnesota, there just are not a lot of e30s, much less extra parts floating around for them. So i though maybe this would be a more practical means of an lsd as apposed to hunting one down.

[briansjacobs]

lock it ;)

[blefevre]

Just keep an eye out on here for a full diff. Shipping isn't THAT much for a full diff and they pop up all the time. I think it might be hard to find someone that is selling just the clutch pack.

[ForcedFirebird]

I have a 4.10lsd I need gone, pm me for details.

[crazyman]

See thats the thing; up here in minnesota, there just are not a lot of e30s, much less extra parts floating around for them. So i though maybe this would be a more practical means of an lsd as apposed to hunting one down.

Ah ok, well that suck's. Well I have a couple of buddy's that do all kinds of things with BMW's, they have a bunch of extra parts. I can look for 3.93 lsd diff for ya, might be able to locate one for free maybe (cus my buddy owes me money LOL). I'll let you know when I find one.

[crazyman]

My uncle a while back spent a bunch of money on a lsd for his ford, so what I did instead of spending a ton of money, I just welded the rear end turned it into a posse. Since that is almost the same as an lsd. I'm just not to sure on how it works on cars.

[u3b3rg33k]

My uncle a while back spent a bunch of money on a lsd for his ford, so what I did instead of spending a ton of money, I just welded the rear end turned it into a posse. Since that is almost the same as an lsd. I'm just not to sure on how it works on cars.

It's not even close. Limited slip ≠ spool. Differentials and spools are opposites.
The idea is to prevent wheel slip relative to to the ground. A spool guarantees a wheel will slip when not going straight.
Spools are of use off road when you want a cheap and effective way to guarantee torque delivery to the ground on a per axle basis.

[crazyman]

It's not even close. Limited slip ≠ spool. Differentials and spools are opposites.
The idea is to prevent wheel slip relative to to the ground. A spool guarantees a wheel will slip when not going straight.
Spools are of use off road when you want a cheap and effective way to guarantee torque delivery to the ground on a per axle basis.

I know that. But on lsd's as soon as your on the throttle and giving it power it locks up and becomes the same thing as a spool. the only difference between the two is that the spool is locked 100% of the time. The lsd is locked when your on the power and un-locked while your coasting. If I wasn't able to get ahold of an lsd for free, I would have welded the diff that was in my 318i. The main thing is how will he be driving it? When you answer that then you will know which setup will work best.

[u3b3rg33k]

You'll be hard pressed to find a limited slip diff that truly locks up 100%. What use would they be in corners if they did?

If you've ever driven a vehicle with a spool rear end, you'll know they are not happy things in corners, and can be somewhat unstable in a straight line. They force the tires to become the differential.

What you really want is a differential that will put torque to the ground in the widest range of operating conditions. A welded diff / spool probably has the narrowest range of useful torque application on paved surfaces in the motive sense.

[///digitalme]

opening up an lsd is a straight forward thing...to be honest its super easy taking apart i think putting it back and torquing everything to spec would be hard