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Fri Aug 31, 2007 5:01 pm

So I bought a Pro-Street Freeway Flyer from Wright Gearbox and I was under the impression it was a posi rear? Anyhow, it seems I need to replace a damaged sidegear or something because it's grinding in all geras as soon as I let out the clutch, so I was thinking a limited slip would be nice. I'm only running about 110 hp, so nothing too crazy is needed.

Fri Aug 31, 2007 5:39 pm

Not sure why you think it would have posi.

Your options are ZF or Quafie. Either case expect to pay well over $1000 for a swingaxle ZF and I don't know if Quafie makes a swing.

Fri Aug 31, 2007 7:36 pm

Quaife LSD does make one for a swingaxle...I think it's somewhere around $1200-1600.

From the Quaife website under ATB Differentials list this:
http://www.autotech.com/quaife/index2.htm

Type 1 Swingaxle
Part #: 10.309.130
Price: $1,495.00

Fri Aug 31, 2007 8:32 pm

i think/know you were under the wrong impression. a super diff is not a posi or limited slip diff.. it adds 2 more spider gears so there are 4 to take the load instead of stock 2 spider gears.

Sat Sep 01, 2007 4:54 am

Doesn't the terms posi track and limited slip refer to the same thing?

Sat Sep 01, 2007 4:55 am

Pfc J wrote: Doesn't the terms posi track and limited slip refer to the same thing?

Posi is a General Motors term.

Yes, the same thing.

Sat Sep 01, 2007 5:00 am

Ah tks Glenn, wasn't sure, I've always heard limited slip.

Sat Sep 01, 2007 7:43 am

You have one other choice that isn't exactly a LSD... but it's a LOT cheaper :)

Gene Berg's "Poor Man's Posi" (swing axle only)
http://www.geneberg.com/cat.php?cPath=12_382_2915

Sat Sep 01, 2007 9:03 am

Posi traction and limited slip are two different things. Posi traction means both wheels are positively locked to the trans. You can tell cars that have posi traction because one wheel will "squeal" when they try to turn. Limited slip costs more because the spider gear is designed to "lock up" when going straight and release when you take a hard turn.

Sat Sep 01, 2007 9:11 am

Alan Willis wrote: Posi traction and limited slip are two different things. Posi traction means both wheels are positively locked to the trans. You can tell cars that have posi traction because one wheel will "squeal" when they try to turn. Limited slip costs more because the spider gear is designed to "lock up" when going straight and release when you take a hard turn.
That's a spool, not Posi.

Sat Sep 01, 2007 10:57 am

Alan Willis wrote: Posi traction means both wheels are positively locked to the trans. You can tell cars that have posi traction because one wheel will "squeal" when they try to turn.
I agree with Glenn, a spool is locked which causes the tires to squeal when they turn.

Positractions & Limited Slips:
Posi and limited slips transmit equal torque to both wheels when driving straight. However, when one wheel spins due to loss of traction, a patch of ice, mud, too much throttle, etc., the unit automatically provides more torque to the wheel that has traction.
Recommended for daily driving, works well in ice, rain, mud and snow.

Posi-traction is a type of limited slip. The name "posi-traction" was used by General Motors for their limited slip differential and the name has been associated with limited slips for many years.

Spools & Mini Spools:
For racing, serious off-road, or crazy hot-rodders, a spool is the ultimate traction differential. Actually, it can hardly be called a differential because it does not differentiate.

Spools have several purposes. First, they lock both left and right axles solid together so that there can be no loss of power due one wheel spinning faster than the other. Second, they usually support the ring gear much better than most other differentials. Last, they can be lighter than a differential, which saves rotating mass as well as un-sprung weight that the suspension has to contain.

In other words...
Posi-traction/LSD/Berg's Poor Man's Posi uses differential gears.
Spool = axles are locked in the differential and has no differential gears.

Sat Sep 01, 2007 2:34 pm

Glenn wrote: Alan Willis wrote: Posi traction and limited slip are two different things. Posi traction means both wheels are positively locked to the trans. You can tell cars that have posi traction because one wheel will "squeal" when they try to turn. Limited slip costs more because the spider gear is designed to "lock up" when going straight and release when you take a hard turn.
That's a spool, not Posi.

Yep. Glenn's right. Positraction is a registered trademark of General Motors Corp, in reference to their particular flavor of limited slip differential.

Installing a spool positively locks both axles together.

Sat Sep 01, 2007 3:20 pm

spool, lsd (quaife or zf), or one legger open diff. your choice.

Sun Sep 02, 2007 5:36 pm

There'a a big difference between a ZF-type limited-slip and a Quaife type torque-biasing differential. This link will generally outline the differences.

http://www.thesamba.com/vw/forum/album_page.php?pic_id=238566

Sun Sep 02, 2007 7:25 pm

Is there a spool available for the swing axle gear box?

Sun Sep 02, 2007 8:41 pm

There's a swingaxle spool for sale listed in the Classifieds - http://www.thesamba.com/vw/classifieds/detail.php?id=129415

Mon Sep 03, 2007 7:08 pm

ashman40 wrote:

Gene Berg's "Poor Man's Posi" (swing axle only)
http://www.geneberg.com/cat.php?cPath=12_382_2915

Would you still be able to use a turning brake with one of these?

Wed Sep 05, 2007 4:00 am

Has anyone tried to install one of these in a S/A or IRS diff?
http://www.phantomgrip.com/

They have a variety of sizes and even offer to make a custom one if you provide the measurements. It's basically sounds like a pair of hardened steel plates sandwiching springs (available in different stregths). The plates are locked in a compressed state until the lock clips are removed. This allows you to install the unit inside the diff. Once release it appears to apply outward pressure on the spider gears, causing friction. This friction along w/ a pivot locking function results in a diff that locks until the friction is overcome. It's described here:
http://www.phantomgrip.com/how_it_works.htm

With all the VW enthusiast out there, someone must have looked into one of these before?

Wed Sep 05, 2007 9:17 am

The "phantom grip" receives a lot of ridicule among the true performance & quality oriented crowd, but it is certainly a WAY better deal than the "poor man's posi". Phantom shoves the spiders outward against the housing, whereas the PMP shoves the spiders into gear bind. Phantom wears out the backside of the spiders, while PMP wears out the teeth of the spiders.

Obviously, neither is a substitute for a true LSD or TBD.