[joec500]

Hi I wanted to ask people who have Limited Slip Diffs to see if it's worth doing if you don't really plan to track the car. Do you notice handling gains from a spirited street driving perspective?

[skinrock]

Yes.

[enrita]

Always worth it. Best mod ever

[Tiago@VRSF]

From my experience I'd say yes. It makes the car feel a lot more planted and gives you a bit more confidence when accelerating through turns.

[fireline43]

I know im gonna sound stupid but I need to ask. I always thought it was either limited slip or posi traction on cars. And posi traction was the good one. I always thought led was a standard thing in all newer cars. What do we have if we have neither?

[enrita]

Eh? What?

[Jeff@TopGearSolutions]

I highly recommend it if you have the means. Makes the car that much better.

[cvc 22349a]

LSD>tune

[skinrock]

Originally Posted by fireline43

I know im gonna sound stupid but I need to ask. I always thought it was either limited slip or posi traction on cars. And posi traction was the good one. I always thought led was a standard thing in all newer cars. What do we have if we have neither?

Posi is just another name for LSD, or specifically the one GM offered (obligatory My Cousin Vinny reference). We have an open-diff, where the power is favored towards the wheel with less traction.

[Figure807]

Originally Posted by fireline43

I know im gonna sound stupid but I need to ask. I always thought it was either limited slip or posi traction on cars. And posi traction was the good one. I always thought led was a standard thing in all newer cars. What do we have if we have neither?

Posi traction, "Positrac," is just a brand of LSD. What we have is an electronic "LSD" - an open differential which sends power to the wheel with the least resistance, which results in wheelspin, the car's traction control then applies the brakes to that wheel, which then makes the other wheel the wheel with the least resistance. Back and forth. Basically just fancy electronics and a regular open differential. A true LSD (Positrac, 4trac, clutch or gear-type) transfers power to the wheel with the most resistance, aka the wheel with traction. I forgot where I read it, but someone said an electronic LSD removes power from the system, whereas a true LSD transfers power within the system. I'm sure you can figure out what is better.

Coming from a RWD 80's Corolla, where a race clutch-type LSD costs ~$900, to a BMW, where an clutch-type LSD costs ~$3500, I was quite shocked

Still on my list of things to do . . .

[ar design II]

+ 1 for yes! great mod!

[benzy89]

NO ONE will dispute whether an LSD is worth it, it's a quality mod. The problem is that is basically cost the same for an LSD as it does to go straight to FBO (tune, DPs, FMIC, DCI, maybe even a CP + Meth if you get a good deal)


$3k can be a lot of coin to drop on a single mod, but if you can afford it spend the $$$

[cstavaru]

Now that I have the LSD, the car feels natural and I'm not even sure that all the traction is from the LSD But then I remember having a lot less traction without it. In corners there is a huge difference but how many corners do you take at high speeds in your daily driving routine ? Also, 2nd gear acceleration is much improved. When climbing a twisty hill there is also a huge improvement in traction. Basically I never feel that the car looses traction in the summer.

Still, the difference with the LSD versus OEM diff is not so significant as others suggest, for daily driving. I would only get it after my car would be fully modded power-wise. Don't forget that the C63 AMG doesn't have a LSD either, and it has a lot more power from factory.

OP, you could first run some Nitto 555R's (drag radials that can be very well driven on the streets and have a wear rating of 100) or 555R2's (stiffer sidewalls than 555R - suitable for twisty roads) to see if they help with traction.

[AlterZgo]

Originally Posted by benzy89

NO ONE will dispute whether an LSD is worth it, it's a quality mod. The problem is that is basically cost the same for an LSD as it does to go straight to FBO (tune, DPs, FMIC, DCI, maybe even a CP + Meth if you get a good deal)


$3k can be a lot of coin to drop on a single mod, but if you can afford it spend the $$$

You have a good point from an economics standpoint. However, I just upgraded to a tune only and I get basically zero traction in 1st gear and part of 2nd. I don't foresee myself getting any additional power adders until I've added an LSD and/or wider/grippier tires.

I can't imagine what a FBO car would be like with an open diff and stock tires... probably like a 662 hp Mustang GT500 with 285 width rear tires - kinda pointless.

[Tiago@VRSF]

You can get a rear diff for about $1000-$1300 and installation for $7-800 if you're not doing it yourself.

While it's definitely a costly mod, anything below 40mph is going to be useless/dangerous and will cause premature wear on your tires with full bolt ons.

[LAE92]

+1, with any type of spirited driving on regular streets, you should really debate how valuable a LSD would be. I would never regret getting one, but I would never push my car that hard on the streets cause I would be too paranoid here in Los Angeles. Too many people focus on power power power, not enough on planting that power, braking, and suspension.

I think if you are anywhere outside of an urban area where you can rip your car thoroughly, you should definitely get an LSD.

[PR3CI5N]

Great thread, I was wondering the same thing as OP. Damn LSD's are so expensive though it's hard to choose this mod when you can by several other mods for less $. I am very sick of no traction though and eating up my $1200 tires...

[The Ghost]

With near 500wtq, the car was almost unusable and unsafe with an open diff. It'd get completely sideways even on a 4th gear hwy roll-on.

If you are just at FBO on 93, it prob isn't that big if a deal.

[skinrock]

Originally Posted by The Ghost

With near 500wtq, the car was almost unusable and unsafe with an open diff. It'd get completely sideways even on a 4th gear hwy roll-on.

If you are just at FBO on 93, it prob isn't that big if a deal.

Even a stock car benefits it imo. And even more so with FBO. At "only" 350rwtq I noticed a huge difference. After I went back to stock diff it was horrible, then I switched to Cobb and with 430rwtq (400 at 2500 rpm) it was downright scary.

[fireline43]

I'm happy i finally asked that question. Coming from a family who talked about owning dusters and vans, positraction was like the cool thing. I remember when I was younger I asked what it was also. And my answer was given an example of when a car is stuck in the dirt. Without posi, only one wheel would try to push out the car, but with posi, both wheels would work. So that's where I got the idea that it was both wheels working while lsd was one wheel. And I never really questioned what the difference was until I came on this board. I mean no one talked about lsd's really in the firebird community that I saw.
This is definitely a more educated car community.

[TurboBimmer]

Totally worth it! One of the best mods!

[Blaster400]

FBO 335 is really pointless without LSD. If I did my mods again it would be the first thing I'd do. HP Autowerks gave me a great deal and great customer service when I ordered mine.