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Discussion Starter · #1 ·
I can see the usefulness of the Limited Slip Diff on the Q2 but is this of real value on the Q4? Also, does it work between the front and rear axles or just from side to side? (Probably a daft question, eh?)
 

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The lsd is a clutch type from ZF and is only installed in the rear axle. Lock up percentages are apparently 23% on accel and 45% on decel. There is not an lsd in the front because the front doesn't always get power. According to Andy Forrest, time attack guy with absurd subaru builds, the effectiveness of a front lsd is reduced when the torque bias greatly favors the rear axle, as is the case in the Giulia. According to other members on the forum, Q4 with the lsd is a money setup. Generally it reduces asr/tc/esc intervention and allows you to enjoy the car mostly free of electronic spoils.
 

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Discussion Starter · #3 ·
The lsd is a clutch type from ZF and is only installed in the rear axle. Lock up percentages are apparently 23% on accel and 45% on decel. There is not an lsd in the front because the front doesn't always get power. According to Andy Forrest, time attack guy with absurd subaru builds, the effectiveness of a front lsd is reduced when the torque bias greatly favors the rear axle, as is the case in the Giulia. According to other members on the forum, Q4 with the lsd is a money setup. Generally it reduces asr/tc/esc intervention and allows you to enjoy the car mostly free of electronic spoils.

Thanks much for the clarification!
 

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I can attest to the fact that the Q4 with LSD setup is money for sure. Grip around corners is fantastic. The LSD combined with the 100% rear wheel bias makes for a super sporty and light handling feel. Plus with the active suspension that comes with the performance package, it really makes the car in my opinion.
Totally agree. ESC never intervenes and the handling is very neutral.
 

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'17 Ti Sport Q4 w/ Active Shocks & LSD
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I can attest to the fact that the Q4 with LSD setup is money for sure. Grip around corners is fantastic. The LSD combined with the 100% rear wheel bias makes for a super sporty and light handling feel. Plus with the active suspension that comes with the performance package, it really makes the car in my opinion.
RMTi has got it exactamundo!!

Best combo short of the Quad owing to a totally neutral exit at speed from tight corners plus remarkable snow and slippery handling. Mild oversteer, point and shoot with throttle on.. snow.. sand... off camber... all conditions, no problems.

Sub 5 second 0-60, too on summer rubber

>:)
 
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This bums me out. I wasn't aware the LSD was not standard on the Sport Q4 Ti until after I picked it up. Anyone know if it's a direct swap or would you need a whole new pumpkin, axles, etc versus the open?
 

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This bums me out. I wasn't aware the LSD was not standard on the Sport Q4 Ti until after I picked it up. Anyone know if it's a direct swap or would you need a whole new pumpkin, axles, etc versus the open?
As it's also tied into the electronic systems, I would doubt it's a simple/cheap swap ......
 

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This bums me out. I wasn't aware the LSD was not standard on the Sport Q4 Ti until after I picked it up. Anyone know if it's a direct swap or would you need a whole new pumpkin, axles, etc versus the open?
As it's also tied into the electronic systems, I would doubt it's a simple/cheap swap ......
Is it? I thought only the QV had the e-diff.
 

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2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
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Is it? I thought only the QV had the e-diff.
Per MacGeek, the traction control system is less aggressive if you have the LSD. Maybe it figures this out on it's own, maybe it needs to be programmed; I do not know.

Also the owners manual (both 2017 and 2018) lists an optional eLSD for the non-Quadrifoglio Giulia models in the fluid capacities section. Does anybody have any idea what that is about?
 

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This bums me out. I wasn't aware the LSD was not standard on the Sport Q4 Ti until after I picked it up. Anyone know if it's a direct swap or would you need a whole new pumpkin, axles, etc versus the open?
As it's also tied into the electronic systems, I would doubt it's a simple/cheap swap ......
Is it? I thought only the QV had the e-diff.
The LSD in the Quad in an electronic LSD and completely different than that of the Ti.

The LSD in the Ti is a purely mechanical device and the ESC has no knowledge it exists.

Until we know for a fact, I'd suggest the open differential uses a different housing than that of the LSD. Finding a good read diffy from a wrecked Ti might be possible. I bet that the after-market LSD vendors will be supporting the Giulia soon enough. The Ti Performance Package for my RWD Ti Q2 was only $1200, about the same price as an aftermarket LSD before installation.

Has anybody checked with their dealer to see what it might cost to get this done after-the-fact? I'm certain it will be much more than $1200
 

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‘19 Giulia Ti Sport Q4
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Man, this thread really makes me feel like a wuss! I mean, I just can't seem to go fast enough on the street to the point where traction in the Q4 feels like a limiting factor. Maybe it's a lack of skills and courage, or the generously open MI curves, but I'm just not comfortable flinging the car through turns at speeds high enough to make traction loss an issue...and my passengers certainly aren't either, because people think I'm frighteningly aggressive already!

I definitely know that loss of grip sensation from my RWD Porsche 928's (one of which is supercharged and put 479hp down on a Dynojet), but I've never been able to get that sensation in an AWD car, I think because the limits are far beyond my ability to test them.

Anyway, I hope to do some performance driving ed in the Giulia and hopefully my build my skills to the point where I can appreciate what an LSD would bring to the performance mix.
 

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2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
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Racer Z,

I tried to do a search, but it seems that the tool will not let me search on a user name + keyword, and it doesn't want to show me results from prior to 9/17.

I am quite certain that I asked MacGeek circa July or August 2017 if the traction control system was "aware" that there is an LSD installed in the car and his answer was "yes". The key being that if a wheel on an LSD axle is slipping the system only needs to apply the brakes about 1/4 as hard to stop the wheel from spinning as compared to the action needed to stop the spinning with an open diff axle. We did not dive into how the system was aware of the situation. In any case, less aggressive application of the brakes by traction control means more control for the driver, more power to the ground, and less side-to-side jerking.

The owners manual lists an eLSD for non-Quadrifoglio models. It is unclear what that is or if any cars have it.

I have no idea of the cost of the LSD differential unit, but the option also includes the adaptive suspension. A set of the adaptive shocks is "only" $4400 from my dealer parts department. Is $1500 for the option a "bargain"? Maybe not in the long term when it comes time to replace those shocks.
 

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Man, this thread really makes me feel like a wuss! I mean, I just can't seem to go fast enough on the street to the point where traction in the Q4 feels like a limiting factor. Maybe it's a lack of skills and courage, or the generously open MI curves, but I'm just not comfortable flinging the car through turns at speeds high enough to make traction loss an issue...and my passengers certainly aren't either, because people think I'm frighteningly aggressive already!
Well, you definitely have to push the car to feel the LSD, but once you do, it is both confidence inspiring and addictive.
 

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Man, this thread really makes me feel like a wuss! I mean, I just can't seem to go fast enough on the street to the point where traction in the Q4 feels like a limiting factor. Maybe it's a lack of skills and courage, or the generously open MI curves, but I'm just not comfortable flinging the car through turns at speeds high enough to make traction loss an issue...and my passengers certainly aren't either, because people think I'm frighteningly aggressive already!

I definitely know that loss of grip sensation from my RWD Porsche 928's (one of which is supercharged and put 479hp down on a Dynojet), but I've never been able to get that sensation in an AWD car, I think because the limits are far beyond my ability to test them.

Anyway, I hope to do some performance driving ed in the Giulia and hopefully my build my skills to the point where I can appreciate what an LSD would bring to the performance mix.
I would never push my car hard enough to get any kind of slippage on "the streets". There are just way too many ways for that to go wrong.

OTOH, get me on a curvy no-traffic country road and Mr. Hyde shows up...

I don't have a open diff RWD Giulia to drive on said roads for comparison. All I know is that my Q4 with LSD acts like it is glued to the road. Even when I push it hard enough to get some slippage it still goes in the direction that I point it with no drama and no obvious ESC/TC intervention.
 

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I would never push my car hard enough to get any kind of slippage on "the streets". There are just way too many ways for that to go wrong.

OTOH, get me on a curvy no-traffic country road and Mr. Hyde shows up...

I don't have a open diff RWD Giulia to drive on said roads for comparison. All I know is that my Q4 with LSD acts like it is glued to the road. Even when I push it hard enough to get some slippage it still goes in the direction that I point it with no drama and no obvious ESC/TC intervention.
Yeah, I didn’t mean around town, but on country roads. It’s just never uninhabited around here, tough it may be rural, and we just don’t have the types of roads with tight turns, series of curves, or decreasing radius turns which help keep speed down but fun levels high.

My roads need high speeds before they start getting fun or challenging, but as I said I don’t have the confidence in my skills (nor the lack of sense for road conditions) to push the car at the speeds it would need to see for LSD or traction control to kick in for lack of grip.

Maybe doing some autocross would reveal those things to me...
 
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Yes thats correct, only the QV has the ELSD unit
I know, I just meant that it could be that a number of the other systems (traction control, abs, electronic dampers, body control, .....) might need to be aware of the presence of an LSD to adapt control strategy to take maximum advantage.
 
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