TheOtherEric

I finally got my new '95 to the track this weekend after a complete engine teardown and LSD rebuild. I'm not one to tout questionable performance mods, but this thing REALLY feels planted during braking. My previous '96 with LSD and 40k miles always felt a little squirrely under heavy braking. Not so with the new LSD in this car. It feels a bit squirrely just at brake application, but you can REALLY feel the rear axle lock up, at which point it starts feeling really planted and stable. Great for trail braking!

So if you're considering having the engine/tranny dropped, you may want to consider an LSD rebuild ($400 for 4 friction plates + labor). What's a few hundred more $$ when you're already that far down the slippery slope?

agdamis

Eric,

Teach me what is LSD. You are from Chicago too to me LSD is "Lake Shore Drive."

GrantG

Limited Slip Differential

akolodesh

Eric,

Did you have the OEM LSD rebuilt? Did you go with Guard or some other aftermarket model originally?
I have considered having my OEM LSD rebuilt at some point. I wasn't sure if it made sense to go that route or to simply go with a higher quality aftermarket product.

TheOtherEric

Alex,
I had the original OEM LSD rebuilt, figuring that $400 would probably get me >80% of the benefits of the $2000+ Guards unit. I'm just guessing there, but so far so good. I like the challenge of trail braking, and having the rears more firmly planted is definitely helpful. Otherwise it's relatively transparent. I think I also may have felt it going thru a slow 2nd gear tight corner, since I felt the car all of a sudden start pushing, not in a bad way mind you.

If you're thinking about getting your LSD rebuilt, I'd suggest having a knowledgable driver take your car on a couple laps to try to assess if your current LSD is working. Some would say " ah that's a waste of time since LSD's only last 30k miles in our cars anyways". But I don't know that. Alternatively, you could look at the slip angles between your rear wheels if you have a data logger taking wheel speed measurements, but that's probably beyond the abilities of most of us.

Coleman

I have a Gaurd LSD on mine and it's sooooo amazing in a curve.. there is this steady power on the ground, you can feel the "bite" -before it was a bit squirrly with the basic non-LSD setup.. kinda expensive for a mod, but if the gearbox is puked out on the floor, it's a good time to slip one in.... My old diff self destructed and I opted for a more bombproof unit...

agdamis

Do all 993 have LSD or was it an option? Would my 97 S have it?

chris walrod

It was an option and should be listed as option 220. With LSD comes ABD as well. Two-piece set if you will

David in Chicago

Eric:

Who rebuilt your LSD? Did the noted $400 cost include R&I?

Regards to all.

TheOtherEric

David,
We sent it to Paul Guard (Guard Transmission; see ads in Pano), although there are likely others who can do it. It included 4 friction plates, some other types of disks, and his labor. Didn't include the ring carrier bolts which I think are like $100+ or the labor of my shop to remove/install. I had the work done at Eurocar (Andy) who I would very highly recommend for *any* work.

David in Chicago

Who/where is Eurocar? A new entrant in the local market? I know you'd been frustrated by the local "regulars."

Regards to all.

Evan

IIRC don't all C4's have both the LSD & ABD?

chris walrod

I am still trying to make rhime or reason to what years Porsche used four vs. two clutch plates in their LSD's? You have four plate version I take it.

Maybe I am a weirdo, (dont answer that), but I feel, for the 993, the LSD is more beneficial on the decel vs. accel. I notice it adds a tremendous amount of braking stability compared to 993's with open diff's.

Remember a few years ago in F1, where some teams had front driveshafts sticking out of their tubs? That was essentially a front, non-driven diff solely for added braking stability. Basically an adjustable device to couple both front tires/wheels together to minimize inside front lock-up..

TheOtherEric

I never got a good answer to the 2 vs. 4 question either. Paul gave me the impression that he could install 4 plates in either type of LSD, though I don't understand exactly why or how. Obviously, i wanted 4 instead of 2.

I'd agree that LSD is more NOTICEABLE on decel than accel, which probably means that this is where it's more beneficial. The braking stability is great. Perhaps if we had more powerful cars we'd benefit more from it on accel.

chris walrod

Absolutely!!!!