[weq92f]

I've an old V8 pontiac 6MT trans am that I toy around in often. It's my beater commuter that I've owned since it was new in 1994. It has an LSD from the factory, which makes the car lots of fun to drive ( and a bit dangerous at times due to no traction/stability control ).

So, now I want the same in my 335 6MT.

Given the limited options, I think I've decided to go for the Quaife unit.

My questions to the board:

o Am I being stupid or just an enthusiast if I spend ~$2000 so I can drift around corners and do doughnuts in wet or dry conditions?

o How difficult a job is it to swap out the internal components of the differential in these cars? Can a local non-BMW-specific transmission shop handle it?

o What should I expect to pay someone to open the differential and do the swap?

o Anybody here install a Quaife, comments?

Thanks,

-Kevin

[scheherazade]

If you drive hard, you *WILL* feel an improvement - but you must drive hard to feel it.

Take that for what it's worth to you...




If you're 6mt, get the AT rear end rack & pinion to boot (3.08 -> 3.46).

You can get a new set from diffsonline for a few hundred bucks.

It's all the same labor, so you might as well hit 2 birds with 1 stone. (I wish I had done this)



I paid : (IIRC, I don't have the papers in front of me...)

Re-build :
- Re-build labor : $350 + oil/shims/whatever
- Machine shop (out of state) to pull the bearing races which were stuck : $200
- Swapping new with old carrier : $250

- Junk yard rear carrier : $750
- Wavetrac : $1200

All said, around $2800 bucks, and I still have my original carrier.



I personally am glad I did it.
The coilovers/camberplates/LSD brought the MOST joy.




Power mods have left me disappointed.
I really like off-the-line performance the most, and this car just doesn't have it like my evo did.

Considering a *stock* evo vs *tuned* 335 :
1st gear : evo pulls so much harder it's not even funny
2nd gear : feels even
3rd and up : 335 pulls harder

Sadly, on a daily basis, I only really get to play up to redline in 2nd... So the car just doesn't have the grunt that I want.

It's just too damn fat...




But the handling after upgrades is plenty fun.

The weight is actually fun for handling, even if it does make the car handle slower.

The fact that the weight lets the car push through turns sideways just makes it that much easier to have fun and slide around. It's not practical for going fast, but it's just 'fun'.

You can say the same thing for crappy tyres. The less grip you got, the more 'fun' the car handles - if you're into that sort of thing.

-scheherazade

[BrianMN]

I'm in the same boat...trying to see if the performance gains justify the high price..

Does anyone know when/how much the stock rear end wears out? For a drastic example, when will it become a one wheel wonder?

I plan on tracking my car next year in the NASA series, and can't decide if the LSD will provide more 'fun' drifting around corners, or if it will improve corner exit speed.

Anybody have any track experiences with LSDs?

[quattr0]

Originally Posted by scheherazade

If you drive hard, you *WILL* feel an improvement - but you must drive hard to feel it.


-scheherazade

Hmm..I don't think you need to drive hard. If you have a green light and about to turn left @ 45deg and the road is wet, once you make the turn and hit it and it won't fishtail due to the help of the LSD then that will make me happy.

I'm actually debating if I should trade in for an M3 or just go back to STi/WRX as they all have LSD. Since the LSD installation will obviously void the warranty. Without warrant on 335i is a bit crazy unless you're mechanically incline.

The M3 would be nice but the low end torque is bothering my decision the most. Guess I just need to test drive it

[E92Fan]

Originally Posted by quattr0

Hmm..I don't think you need to drive hard. If you have a green light and about to turn left @ 45deg and the road is wet, once you make the turn and hit it and it won't fishtail due to the help of the LSD then that will make me happy.

I'm actually debating if I should trade in for an M3 or just go back to STi/WRX as they all have LSD. Since the LSD installation will obviously void the warranty. Without warrant on 335i is a bit crazy unless you're mechanically incline.

The M3 would be nice but the low end torque is bothering my decision the most. Guess I just need to test drive it

Why would an LSD void the warranty on the car? It might void a warranty in relation to the driveshafts, but it won't effect the warranty on the engine or the electronics or anything else like that.

[scheherazade]

Originally Posted by quattr0

Hmm..I don't think you need to drive hard. If you have a green light and about to turn left @ 45deg and the road is wet, once you make the turn and hit it and it won't fishtail due to the help of the LSD then that will make me happy.

Yes, you will feel it engage at those times with the nannys off.

Originally Posted by quattr0

I'm actually debating if I should trade in for an M3 or just go back to STi/WRX as they all have LSD. Since the LSD installation will obviously void the warranty. Without warrant on 335i is a bit crazy unless you're mechanically incline.

The M3 would be nice but the low end torque is bothering my decision the most. Guess I just need to test drive it

If I was in the market, I'd be in the market for :

- Used evo (which is what I had)
- Murtaya (sick quick, i mean omfg quick. And very light.)
- Used GTR (I've seen them for $65k... more than I want to spend but as far as supercars go, it's about the highest value you can get)

You can pick up tuned cars pretty cheap nowadays.

A moderately tuned evo 9 for $20k or so...
Check out evolutionm.com

Or you can pick up one of the two 700 awhp evos that AMS has for sale... $33k and $35k I think...
(Look at the used pars section on their web site, 2 cars for sale)

Check out NASIOC for some deals on moderately tuned STIs.

-scheherazade

[quattr0]

Originally Posted by E92Fan

Why would an LSD void the warranty on the car? It might void a warranty in relation to the driveshafts, but it won't effect the warranty on the engine or the electronics or anything else like that.

Sorry but I'm noob but don't you have to open up the tranmission for LSD installation? If so, wouldn't that void the warranty if something is wrong with trans?

[scheherazade]

Originally Posted by quattr0

Sorry but I'm noob but don't you have to open up the tranmission for LSD installation? If so, wouldn't that void the warranty if something is wrong with trans?

No transmission involved.

Drive shaft leaves transmission and goes to the rear of the car.

It enters the carrier on the front, and two half shafts exit on the left/right of the carrier, and go to the wheels.

The LSD is inside the carrier.

-scheherazade

[stressdoc]

There are several excellent informative threads on LSDs.

Bottom line is that if you value handling under power transitions, a good LSD makes a big difference. But IMO if you are installing a LSD then you also need to tighten up the suspension, which is more $ still. In the end you can build a great handling car that is on par with the M3, but it takes $.

Unfortunately there is no simple easy cheap way to install a LSD into your final drive. Very, very few local differential shops can do the job right because they can't get the shims.

The right thing to do is go to one of the few shops that have the knowledge and parts to do the job correctly. Or buy the whole pumpkin, and get the SIB so the shop knows they need a 55mm thin wrench, how to back out the nuts correctly, etc.

[Mike7341]

Do you think it's worth it if all I mainly do is drag racing.... Does it help alot with launch... Well at least I'll be able to warm up BOTH tires. Coming from a awd jeep srt8.... I know what you mean by how lousy these pull in 1st gear. Trying to decide Between the quaife, wavetrak, OS Giken.... Then there's a really pricey one, but I don't want to spend that much..... And as far as warranty... Does it set off any codes? How can they tell u did it?

[E92Fan]

Originally Posted by Mike7341

Do you think it's worth it if all I mainly do is drag racing.... Does it help alot with launch... Well at least I'll be able to warm up BOTH tires. Coming from a awd jeep srt8.... I know what you mean by how lousy these pull in 1st gear. Trying to decide Between the quaife, wavetrak, OS Giken.... Then there's a really pricey one, but I don't want to spend that much..... And as far as warranty... Does it set off any codes? How can they tell u did it?

No codes as differentials are mechanical devices, and a dealer can't tell you have an LSD unless he takes apart the differential casing, which is highly unlikely. Even then, I doubt any tech will be able to tell it isn't a standard differential in there, as most of the techs won't even have seen inside the casing before!

Or if the car is up on a ramp, and the technician rotates one rear wheel and happens to notice the other one moving !!!

There's a link to a Quaife LSD review in my sig - one of many good write ups on this forum about LSDs

[stressdoc]

No codes, my dealer had no problem with the Quaife, but he did have someone come in with a blown up pumpkin that somehow installed a locker.

I can't really advise you regarding drag racing. I find the LSD great for amateur drifting and twisties. Handy in the snow too.

[scheherazade]

Originally Posted by Mike7341

Do you think it's worth it if all I mainly do is drag racing.... Does it help alot with launch... Well at least I'll be able to warm up BOTH tires. Coming from a awd jeep srt8.... I know what you mean by how lousy these pull in 1st gear. Trying to decide Between the quaife, wavetrak, OS Giken.... Then there's a really pricey one, but I don't want to spend that much..... And as far as warranty... Does it set off any codes? How can they tell u did it?

If you're rear wheel drive, the OS giken will serve you very well.

It's especially well suited for drag and drifting (progressively locks on acceleration).

Full power application is basically like having a solid axle in the rear. Exactly what you want.

Under normal conditions (i.e. when not spinning the rear wheels), the progressive locking effect on power application also prevents oversteer, which is good in RWD since it neutralizes the handling a bit as you accelerate through a turn.

If I were RWD, it would be my first choice.

The OS Giken has 2 versions, street and drag.
Street has drilled clutches to let more oil in between them, so it makes less noise - but it costs more.

(AMS sells them, and so does Mach5 (near chantilly VA). I looked around earlier when I was looking for one. However I got the Wavetrac since I'm AWD)

-scheherazade