Oleg

iTrader: (1)

Me again, 2 threads in one day...
Does anyone know if that gear-based LSD from quaife is available yet?

jeffw

Here's the main thread on the Quaife diff. Short answer is that it's coming soon.

I would give you a hard time about using search, but the special characters in the title of the thread make this not show up when you search for "quaife."

https://my350z.com/forum/engine-and-drivetrain/95876-quaife-lsd-want-one.html

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Jeff

bullseye

The Quaife automatic torque biasing differentials for the 350Z/G35 will be worth waiting for. But it's taking a long time to complete this project, isn't it? Whew.

Secret Z

I think the reason it is taking so long is that they are making a different gear set...correct? Supposedly that's what they do on every LSD they make.

Z1 Performance

iTrader: (564)

not for nothing, because I know the Quaife is superior to the stock Viscous, but on a RWD, why on earth would you want a gear type LSD? as soon as one drive tire loses traction, which is exactly what happens when you push a Z hard, its understeer city.....

bullseye

I don't disagree, I'm just trying to understand what you just wrote...

A Quaife ATB Differential is bullet-proof. It'll last forever without wear, even under racing conditions. It's guaranteed for life. Its operation and transfer of torque from side-to-side are silent, swift & seamless. The quality of this unit's construction and the driving improvement it delivers are clearly superior to those of a stock unit, and probably all after-market LSDs. Do we agree so far?

In straight-line acceleration, the unit instantly transfers torque to the wheel with greater traction. No waiting for a viscous fluid and clutch plates to bind. Wheel-hop is greatly reduced. Both wheels pull hard without slip, up to a limit. Then it's two smoking tires... Right?

Can we assume the anti-roll bars, tire pressure, and so forth are adjusted to make the handling balance neutral? If so, during hard cornering, wouldn't a Quaife ATB work to maintain that fine balance? During very, very hard cornering, both tires would slip, but recovery would happen sooner than with a stock LSD. You would be able to get back on the gas sooner with an ATB, exiting corners with more speed.

I don't understand how an ATB induces "net" understeer. I believe an ATB, if you can say it induces understeer at all, produces just enough to offset the oversteer created by a slipping [inside] tire. The net effect would be neutral. Am I right, or am I missing something? Please explain. Thanks.

Z1 Performance

iTrader: (564)

just as I said - if one tire loses traction (ie the inside tire lifts), which is what happens on a Z, the LSD action is gone and the car will push badly. On a FWD or AWD car, using a helical/gear type LSD (whcih is what the Quiafe is) is a fantasitc way to improve traction - for a RWD car, its less than desirable IMHO for all out performance

jeffw

Is it not possible to tune a suspension to make a car neutral or oversteer off-throttle? Everything I've read says that clutch-plate diffs are best for racing. However, they appear to require more maintenance, don't engage instantaneously, and if configured aggressively they seem to lock up when you don't want them to. The helical gear diff seems to be a nice compromise for serving both street and track.
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Jeff

The Brickyard Rat

iTrader: (1)

Anyone know what a Quaife LSD will cost?

g356gear

iTrader: (12)

I am gonna say $1200-1500

Z1 Performance

iTrader: (564)

yes it is totally posisble to tune the suspension to be neatural - but thats not the point really. The only disadvantage to the clutch type ones is noise. There is no added maintenance that I haev ever experienced with them (one of my cars make ~600 whp, and has had the same clutch type LSD for 5 years no, with a variety of mixed driving from street to drag to track). What's more, they are totally adjustable

Ec2k1gt

iTrader: (10)

I purchased a quaife lsd for my 3g eclipse a few months before i sold it, let me tell you that thing was built like a ****in tank possibly the best upgrade i did to the car after going turbo, solved many of my traction issues... all in all it took quaife a little over 2 years to deliver the final product to the 3rd gen communtiny

Resolute

iTrader: (2)

Z1 is right. You would be foolish to tune your suspension for neutral handling while dog lifting the rear end in mid-turn. What would be the point? Helical units like the Quaife will require both tires to have resistance to work. The worm gears inside the diff only turn one way under resistance, which delivers the power seamlessly to the wheel that slips the least, but also requires that the less burdened wheel still have some resistance. Once the inside wheel becomes unladen, the inside wheel will spin just like an open diff. In mid turn, coming on the power will transfer weight to the rear, but if the back tire lifts, then you lose that forward acceleration and weight transfers back to the front, and you push. Of course, if you run too high a bias ratio on a clutch type, then you will push (or power oversteer if you've got the grunt) simply because the outside tire will not be able to spin faster than the inside and push the car in a straight line, but that's why they are typically adjustable. Clutch types will also typically generate LESS heat than a Helical (all those gears...) and noticably less parasitic loss than a Helical (again, all those gears to turn..). And weigh less. Of course, the Quaife is very seamless and effective if you can keep the tires on the ground.
Will