Anybody know where i can get a new quaife at the best price?

Thanks!
Bill

IIRC from a past thread, GPR has good prices...

thanks will give them a try!

Hmmmm, you up to something Bill? Is a Quaife or a ZF/GT LSD set to 60/40 or 80/20 better for the track? I've heard the old style clutch systems are better for the track, but I'm not sure if a quaife would work as well. I think you get the limited slip when off throttle with a ZF/GT LSD. Just looking out for your interests.
I think it'll cost a pretty penny to install as well, FYI

Hey Nathan!

Going on the recomendation of Charlie over at Intersport. The quaife we can adjust where as the LSD (as far as i understand it) will not be quite as flexible? For the install, a friend with some experience in trannies (you know the name) has offered to help put it all together. Any way you slice it, it is gonna be expensive, but with 1700 lbs or so and 220-230hp, will definitely be needing a better solution than a 901 with different 4th and 5th.

Will take a look at older threads discussing this and/or hope people chime in with their experiences?

The Quaife is English...the Euro is realllllly strong against the dollar and the company does not discount it's product.....


BTW....I have a built 901 trans with an LSD ready to go....

Remember - if one rear wheel looses grip, say in a tight turn, the Quaife stops working.

Ken

Hows 'bout $750 for the tranny Mikey?

Lots of threads on LSD vs Quaife for track and axing.



Geoff

Will be East Coast GT5 car...

Willing to listen to the collected wisdom and have read the old threads where quaife shows up. Thoughts went 50/50 with my hp target.

Mike, dont you want like a bajillion dollars though?

I'll take $3,000....FRESH REBUILD with zero miles....the Quaife was 1200, then there is the H gear and the billet plate....try doing one yourself or having one built....you'll have 4K+ in it....

QUOTE (KenH @ Feb 24 2005, 09:35 AM)

Remember - if one rear wheel looses grip, say in a tight turn, the Quaife stops working. Ken

Ken,

huh...?
I thought that was the exact reason for a limited slip. If one wheel lifts the other gets its power.

confused entirely now

brant

The best price on a Quaife is at www.thescirocco.com DLee

QUOTE (brant @ Feb 24 2005, 12:45 PM)

QUOTE (KenH @ Feb 24 2005, 09:35 AM) Remember - if one rear wheel looses grip, say in a tight turn, the Quaife stops working.   I thought that was the exact reason for a limited slip. If one wheel lifts the other gets its power. confused entirely now

yes, that is the exact reason for a limited slip, but a Quaife / Gleason / Torsen is NOT a limited slip -- it is a torque-biasing diff.

0 torque, 0 bias... each wheel must provide -some- resistance to the torque for a Torsen to work.

OTOH, they are expensive, and quite heavy.

(i have never heard of an adjustable Torsen, but i haven't researched all the options. certainly there didn't seem to be any means of adjusting the one i bought for the GTI (and never used, still for sale ...))

Rich what year GTI???? I am in need the TDI will burn the inner tire in any turn, in 1st, 2nd, 3rd, 4th, and if it is damp 5th gear. To much torque, nah can never have to much torque My 98 TDI looks stock, but then so do all my cars.

QUOTE (914forme @ Feb 24 2005, 01:17 PM)

Rich what year GTI???? I am in need the TDI...

probably too early to help you in a TDI ...

... 020/9A vintage (Mk-I / Mk-II)

Hep - 0 torque, 0 bias

ZF can be set at 40% or 80% slip.

I just installed one and do not remember it being that heavy.

Ken

QUOTE (ArtechnikA @ Feb 24 2005, 11:09 AM)

QUOTE (brant @ Feb 24 2005, 12:45 PM) QUOTE (KenH @ Feb 24 2005, 09:35 AM) Remember - if one rear wheel looses grip, say in a tight turn, the Quaife stops working.   I thought that was the exact reason for a limited slip. If one wheel lifts the other gets its power. confused entirely now yes, that is the exact reason for a limited slip, but a Quaife / Gleason / Torsen is NOT a limited slip -- it is a torque-biasing diff. 0 torque, 0 bias... each wheel must provide -some- resistance to the torque for a Torsen to work. OTOH, they are expensive, and quite heavy. (i have never heard of an adjustable Torsen, but i haven't researched all the options. certainly there didn't seem to be any means of adjusting the one i bought for the GTI (and never used, still for sale ...))

So Rich and Ken,

how much resistance would each wheel need to provide in order to have the diff functioning?

I always thought that the 80%ZF was superior for track racing. Until recently. My race shop (AJRS) claims that there is a HP threshold. somewhere around 225hp, the ZF becomes supperior, and below that the torque biasing is superior (at least in lap times)

as it was explained to me its due to the TB allowing you to drive smoother. And we all know that in a low HP car like a 914 smoothness counts.

I've been running a locked diff. I improved my time by 2 seconds a lap (with the same tires) so it definitely helped, but I AM NOT SMOOTH anymore. It took me quite a while to learn how to drive it completely different to get that 2 seconds a lap. Initially the locked diff was slower.

So how much pressure does it require to make the TB work? I'm guessing (based on AJ's comments) that the TB functions with even partial pressure upon it.

The general rule is 40% for AX & 80% for Track.

Mine is set for 80% and works well on the track but I have not run an AX with it yet.

I do not believe HP would be a determining factor when choosing a ZF or TB diff. Others will need to comment on that.

Those I have talked to preffer the ZF for track use because it is "always" working - accelearation, braking, rear wheel lift.

Rear wheel lift is probably a bigger problem when AXing.

Not sure I understand your comment "how much resistance would each wheel need to provide in order to have the diff functioning".

The ZF is always functional, acceleration and deacceleration. It uses a "plate/disk" system that senses drive shaft input and wheel load to manage the "slip".

I would try and talk to as many "drivers" as possible. It is expense to have a new differential "fitted".

There is a possiblity the Quaife my not work all the time - but the ZF will always work.

Ken

QUOTE (brant @ Feb 25 2005, 10:39 AM)

how much resistance would each wheel need to provide in order to have the diff functioning? ...(AJRS) claims that there is a HP threshold.  somewhere around 225hp, the ZF becomes supperior... ...how much pressure does it require to make the TB work?  I'm guessing (based on AJ's comments) that the TB functions with even partial pressure upon it.

short answer: i have no idea, and therefore the rest must be categorised as speculation and conjecture - which you are free to disregard as such. as i don't have engineering test numbers, nor access to an instrumented test vehicle and acceptable track, i consider it all subject to discussion, test, investigation, and development - in which case, we'll probably all learn something ...

some background, which was spelled out in pithy form for me only recently (which means i probably knew and understood it on some level before, but i didn't know i knew it...). the "magick" in the Gleason Torque-Sensing (TorSen) diff is that it's practically impossible to back-drive a worm gear. i'd have to look again at the exploded pictures of the guts of a TB diff (and quite the machinework nightmare *that* is...) but with both wheels turning the same speed, there is no relative motion. so far so good.

with differential rates, it seems there's a resistance applied by one wheel, and a gear-effect opposition that applies more torque to the slower wheel (that'd be the inside, in a normal turn)

when that wheel begins to slip, becoming the *faster* wheel, more torque is transferred to the outer (non-spinning) wheel.

so - seems like the inner (slipping) wheel has to provide enough resistance to overcome the frictional losses in driving the internal worm gears. what is that, measured in real torque? i have no clue, but considering how hard it is to achieve any kind of relative motion with a Quaife diff just sitting in your lap, i bet it's somewhere between nontrivial and substantial.

this kinda goes with the "225HP" threshold - that seems a plausible number for the point at which a sticky race tire can be broken loose letting the clutchpack work better. i think that number is probably lower in limited-traction conditions, such as a rallye car's loose gravel or the glare ice i faced this morning just trying to move my car into a parking space.

Mark Donohue was a big fan of the spool and a very smooth driver. one drawback to the spool is that the "friction circle" technique tends to promote understeer, because the braking-while-turning and the accellerating-while-turning forces with equal drive to the back wheels tend to make the car go straight. only if you can consistently develop adequate slip angles with the drive wheels can the car be pursuaded to turn. (hence the change in driving styles you observed.)

917's and 935's had very beautiful titanium spools, and WEVO makes a similarly beautiful spool for the 915 (although i'm pretty sure it's steel). 917's and 935's had enough power to produce rear wheel slip...

QUOTE (KenH @ Feb 24 2005, 08:35 AM)

Remember - if one rear wheel looses grip, say in a tight turn, the Quaife stops working.   Ken

I don't understand this statement, would you please elaberate.

The Quaife locks between 15% and 80% depending on the amount of change between the wheel that is loosing grip/spinning and the wheel that has hook-up. Your statement, if i'm reading it correctly, is what a non-limited slip does.

Now a clutch pack diff will slip at what ever the precent is throughout the entire range. If its set at 80%, at any speed, it will slip 80% everywhere.

Am i mis-informed?

Thanks, Don

QUOTE (BigD9146gt @ Feb 25 2005, 11:56 AM)

The Quaife locks between 15% and 80% depending on the amount of change between the wheel that is losing grip/spinning and the wheel that has hook-up. Your statement, if i'm reading it correctly, is what a non-limited slip does.

you are correct in that with a torque-biasing diff, when a wheel has ZERO grip, it will spin; in this reqime, it acts just like an open diff.

similarly, the torque-biasing diff works only under drive - not overrun (braking.

QUOTE (KenH @ Feb 25 2005, 09:25 AM)

The general rule is 40% for AX & 80% for Track. Mine is set for 80% and works well on the track but I have not run an AX with it yet. I do not believe HP would be a determining factor when choosing a ZF or TB diff. Others will need to comment on that. Those I have talked to preffer the ZF for track use because it is "always" working - accelearation, braking, rear wheel lift. Rear wheel lift is probably a bigger problem when AXing. Not sure I understand your comment "how much resistance would each wheel need to provide in order to have the diff functioning". The ZF is always functional, acceleration and deacceleration. It uses a "plate/disk" system that senses drive shaft input and wheel load to manage the "slip". I would try and talk to as many "drivers" as possible. It is expense to have a new differential "fitted". There is a possiblity the Quaife my not work all the time - but the ZF will always work. Ken

Ken,

my comment about "how much pressure" was aimed specifically at the comment about a TB not functioning when a wheel was lifted. To rephrase, I was asking if a TB would work when say a wheel is unweighted some, but still had 100lbs.. (or 200lbs, or x lbs) of weight on it.

each of us has to make our own decisions and findings.
I usually take advice from my the local guru who has been giving me good advice for 15years. my guy, AJ installed my locked diff (not really a spool, just a welded diff) and has never given me bad advice.

I believe that the HP threshold is based somewhat on smoothness. I'm theorizing here, but would guess he was trying to explain to me that a high HP car can still be faster on a track by improving traction and giving up smoothness... Where a lower HP application is faster on the track by highlighting the smoothness from a TB diff and has limited gains in traction due to the ability of a race tire in a dry situation to put down a good amount of torque.

So What I was asking is in reference to the comment that
"a TB diff does not work when one wheel is unloaded"

do you know if that is true only when fully unloaded or still true if just partially unloaded?

I trust my guy and will put together next years box with a TB, but still love to learn.

QUOTE (ArtechnikA @ Feb 25 2005, 09:27 AM)

this kinda goes with the "225HP" threshold - that seems a plausible number for the point at which a sticky race tire can be broken loose letting the clutchpack work better. i think that number is probably lower in limited-traction conditions, such as a rallye car's loose gravel or the glare ice i faced this morning just trying to move my car into a parking space. Mark Donohue was a big fan of the spool and a very smooth driver. one drawback to the spool is that the "friction circle" technique tends to promote understeer, because the braking-while-turning and the accellerating-while-turning forces with equal drive to the back wheels tend to make the car go straight. only if you can consistently develop adequate slip angles with the drive wheels can the car be pursuaded to turn. (hence the change in driving styles you observed.)

Rich,

thanks for your time, and thanks for writting all of this out!

I was very clearly told when I went with the locked diff that I would:
a) need to re-learn the driving and
reminded that in (low traction) rain or sand, things would get scarry fast.

I had to re-learn to deal with the understeer. Kinda like the 911 guys have Known for years. Its truly a "dirt-track" style to get the car to rotate. You literally force the rear into a slide until you are pointing the direction you want, and then apply power to go straight.

for that reason, I'm guessing that the whole differential debate is based upon some cars/some levels of HP/and some driving styles are better off with one type over the other.

I think that you can still be smooth with a locked diff/spool, but its a whole different type of smooth which involves constant "smooth" drifting and dancing on the traction limit.

http://www.quaifeamerica.com/

They should be able to answer questions about the TB's operating range.

The understeer was not that great on mine. 2223# car, 225# rear springs, stock rear swaybar, 22mm front torsion bars, 22mm front sway bar set 1-1/2".

Still "tweeking".

Ken

I've been told, that the understeer is not bad with the TB...
Its good that you confirm that.

Its on the locked diffs that the understeer is significant.
The rear remains locked at all times (like an 80%ZF except more so)

I anticipate that a TB diff will let me go back to a much smoother and less "dirt track-ish" driving style...

Thus the exact reason the TB is supposed to be smoother and possibly quicker (according to some)

I've made up my mind long ago.. my wallet just won't let me play yet.