Wanna upgrade to a 3.73 LSD

[th30d0r3]

Guys

I'm very new here, and I think this is my first post, so please bear with me, I'm also in the UK so I may write a little different :wink:

I have a standard 318TI and I would like to install an E30 3.73 LSD and therefore have a few questions

What donor car should I aim to find this part in?

I also understand that I need all these parts

E30 rear differential
E30 axles/halfshafts (both)
2 quarts Red Line 75W-90 gear oil
CV joint grease
33 41 1 124 945 (x2) drive flange collar nut securing plate
33 41 1 128 346 (x2) CV joint circlip (if swapping CV joints)
07 12 9 964 672 (x4) driveshaft self-locking nuts

However I'm a little confused as to iff all these parts are definately required after reading the numerous posts on here, namely the Axles.

And for the M coupe Cover I'll need:

33 11 2 228 335 M Coupe diff cover
33 11 1 210 405 diff cover gasket
33 11 1 206 166 speedo o-ring (optional)
33 11 1 212 682 (x2) drain and fill plugs (optional)
07 11 9 963 355 (x2) crush washers
07 11 9 914 114 (x2), 10mm x 25mm
07 11 9 921 541 (x2), 10mm x 75mm
07 11 9 921 522 (x4), 10mm x 85mm

I'm not gonna do it myself, I'm gonn get my garage to do it. but are there any difficulties I will face?

[L84THSKY]

What's your objective, more torque, limited slip, or both? If you want just limited slip, then get a ratio the same as our standard 3.45. You won't need to swap CV joints no matter which choice you make.

Guys

I'm very new here, and I think this is my first post, so please bear with me, I'm also in the UK so I may write a little different :wink:

I have a standard 318TI and I would like to install an E30 3.73 LSD and therefore have a few questions

What donor car should I aim to find this part in?

I also understand that I need all these parts

E30 rear differential
E30 axles/halfshafts (both)
2 quarts Red Line 75W-90 gear oil
CV joint grease
33 41 1 124 945 (x2) drive flange collar nut securing plate
33 41 1 128 346 (x2) CV joint circlip (if swapping CV joints)
07 12 9 964 672 (x4) driveshaft self-locking nuts

However I'm a little confused as to iff all these parts are definately required after reading the numerous posts on here, namely the Axles.

And for the M coupe Cover I'll need:

33 11 2 228 335 M Coupe diff cover
33 11 1 210 405 diff cover gasket
33 11 1 206 166 speedo o-ring (optional)
33 11 1 212 682 (x2) drain and fill plugs (optional)
07 11 9 963 355 (x2) crush washers
07 11 9 914 114 (x2), 10mm x 25mm
07 11 9 921 541 (x2), 10mm x 75mm
07 11 9 921 522 (x4), 10mm x 85mm

I'm not gonna do it myself, I'm gonn get my garage to do it. but are there any difficulties I will face?

[scabzzzz]

do the 3.73 you wont regret it. it'll add what feels like 30 horsepower.
you can get a 3.73 from automatic e36 sedans... a lot of limited slip diffs were optional so theres no telling which cars have them. i think the e30 m3 got it, because thats what mine came out of. could be wrong. i havnt noticed a certain formula for which cars get open diffs or lsd's. to the best of my knowledge all you're going to need is the diff and the necessary fluids. if you're changing out the diff cover, you'll probably want all that stuff like the crush washers and cover gasket. im pretty sure thats it. bolt it up. hook up the driveshaft and axles. plug in the speed sensor. enjoy sliding the ass end out thanks to short gears.

you could even do a 4.10. those seems to be easier to find in the e30s. 4.10 limited slip comes in the automatic 325i's. i know that for a fact.

[mooseheadm5]

E30 325i manual and early autos got a 3.73 with available LS. E30 M3 got 4.10LS. E30 4 cyl got small case diff (bolts right in, same axles) 4.10 or 4.27 (convertibles) avail. in LS.
-Paul

[scabzzzz]

well there ya go. i was somewhat right.

while its out pull the cover off and check out the teeth on the gear things. make sure its not all ****ed before you put it in.

[th30d0r3]

Guys

Waht about a 3.91 LSD???
What charactoristics will I notice?

Reduced MPG?
Lower Top Speed? (how much)?
Louder driving experience?

[DustenT]

If you do any highway driving, avoid anything above 3.45, unless you plan on doing a 6 speed tranny swap at the same time. I run over 4000 rpms at highway speeds (80-85 mph) with a 3.45, anything above that is going to be really running the rpms up...Just my opinion.

[th30d0r3]

You know what, you're so right.
Would I benefit much from a 3.45 with LSD?

[L84THSKY]

Yes, you would have limited slip, and a stronger diff. The only way to have the best of both worlds is to have a 3.45/3.46 LSD and a LTW flywheel. That way you get the torque and the limited slip, with no downsides. Get a 3.46 from a 6 cylinder car, and you can throw on the M-coupe cover.:smile:

You know what, you're so right.
Would I benefit much from a 3.45 with LSD?

[th30d0r3]

Ok that sounds interesting, what is an LTW flywheel?? and where can I get one?
do you know which 6 cyl car has the 3.46 LSD?
I noticed a 3.61 LSD on ebay today, would that make much of a difference?


Yes, you would have limited slip, and a stronger diff. The only way to have the best of both worlds is to have a 3.45/3.46 LSD and a LTW flywheel. That way you get the torque and the limited slip, with no downsides. Get a 3.46 from a 6 cylinder car, and you can throw on the M-coupe cover.:smile:

[mooseheadm5]

733i up to 9/81 (but you can't use it b/c the cover is different and can't be changed to E30 style), 735i (all), 635csi up to 6/87 (after that 3.64 on manual and 3.91 auto) and 528e auto from 3/87
-Paul

[L84THSKY]

Do a search. If you change your ratio, somethings gotta give.
Stay as close to stock ratio as possible.

Read my thread
http://www.318ti.org/forum/showthread.php?t=11529

Ok that sounds interesting, what is an LTW flywheel?? and where can I get one?
do you know which 6 cyl car has the 3.46 LSD?
I noticed a 3.61 LSD on ebay today, would that make much of a difference?

[uaza]

L84THSKY,

http://cgi.ebay.com/ebaymotors/BMW-E30-E28-Limited-Slip-Differential-LSD-3-46-Rebuilt_W0QQcmdZViewItemQQcategoryZ33731QQihZ013QQitemZ230063235682QQrdZ1QQsspagenameZWDVW
this case, it's a 3.46 LSD... if i want to swap to this one what exact parts would i need?? (i'm sorry if its been asked but english is not my first language and I'm having some hard time trying to understand all the technical terms here..)

[uaza]

btw I only want LS, I'm OK with the stock gear ratio.