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ITA Racer
12-26-2004, 08:03 PM
Has any one heard of the Phantom limited slip diff? Is it any good. It is reasonably priced. Much cheaper than a quaiff diff.

Andy Bettencourt
12-26-2004, 09:31 PM
For every one posative, I have heard 9 negative.

For the rigors of racing, don't throw good money away. I would ask all the drivers of the brand of your car what provides the best value...you may get a few different answers but it will save you $ in the long run.

AB

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Andy Bettencourt
New England Region, R188967
ITA project SM
www.flatout-motorsports.com

Chris Wire
12-26-2004, 11:22 PM
You'll never go wrong with a Torsen, which range from $400 used to almost $700 new.

You can use an OEM diff from the 86-88 models with decent success, if you shim it properly to tighten it up a bit.

Stay away from the vicous-style 89-91 OEM diff, as it will quickly give up under the rigors of racing. Some of the FB guys weld up the factory unit with mixed results, but I haven't heard of anyone using one in a FC.

Andy is right. Don't waste your money on unknowns when it comes to the diff. A full blown Torsen 5.12 will run you $1500-$2000, but it will last you many years when properly maintained.

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Chris Wire
Team Wire Racing
ITS Mazda RX7 #35
[email protected]

Greg Amy
12-27-2004, 11:09 AM
ITA Racer (what's your real name?),

The Phantom Grip is nothing more than a preload device. They are springs that are added behind the side covers of your R&P to exert preload on the spider gears. By doing so you're effectively binding up the gears, reducing their ability to spin.

As you can imagine, this induces some extreme loads on the gears, bearings, and side covers. While a little preload is not bad (such as what VW did with the Rabbit GTi) a lot of preload will quickly wear or break expensive components. Get enough wear material in the transaxle and you could be looking at needing a new one.

At best it will be ineffective long-term; at worst it will damage your transaxle. Either way, you are much better off spending smart money and doing it correctly.

Greg Amy

gran racing
12-27-2004, 07:18 PM
Wow! 1,500 - 2,000? That is pretty darn expensive.

I'm getting the OPM LSD this offseason which will run $700 plus $300 for them to instal.

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Dave Gran
NER ITB #13
'87 Honda Prelude si

ShelbyRacer
12-27-2004, 10:11 PM
Well, I have a PG in my street car (98 Neon SOHC with a few mods), and I can tell you that it basically does nothing. Now, I had my trans apart anyway when I installed it, but I'm glad I didn't spend any money on it really. At this point with both front wheels off the ground, I can grab one and spin it quickly, and the mass of the other one is enough that it won't spin right away. If I do it slowly, both spin together. I figure that's a breakaway torque of about 50 ft.lbs. on the old estimometer.

If you want to make something and you can't afford a torsen, get some tool steel blocks machined up and use high pressure machine springs between them. It'll help a lot to machine the spider gears down so as to have a larger, flatter surface for the block to push against. Just remember, this is using friction to do something where there shouldn't be much friction, so your wear *may* (read-will) increase. Just inspect it regularly and you'll *probably* catch any problems before too much damage is done...

BTW- the above idea should NOT be attempted by anyone who actually can get the correct setup LS for their car. For the rest of us that are screwed, it's all we've got...


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Matt Green
"Ain't nothin' improved about Improved Touring..."

Richy Gonzalez
12-29-2004, 10:24 PM
Originally posted by gran racing:
Wow! 1,500 - 2,000? That is pretty darn expensive.

I'm getting the OPM LSD this offseason which will run $700 plus $300 for them to instal.



Everyone that I've ever known with the OPM unit has been satisfied with them. They work good and last pretty long. But at 700 bucks, it is by far the cheapest in the good unit arena. Look at Quaife, Kaaz, Mugen and you'll see the price difference.

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Richy Gonzalez
GB Racing<A HREF="http://groups.msn.com/TheGonzalezFamilyRichySheilaandNyah/projectitacrx.msnw" TARGET=_blank>
#24 ITA CRX For Sale $7500.00 FIRM + $1000.00 with Trailer</A>
LAMIN-X Protective Films (http://www.lamin-x.com)

joeg
12-30-2004, 09:43 AM
I have a PG, a Quaife, a welded diff and an open diff.

The PG and open are real close in performance. The PG generates more metal filings in the differential fluid, however.

The Quaife works very nicely but it is HEAVY.

This heaviness must have some negative performance aspects.

The welded diff works great on a dry track, at speed.

Everywhere else it is a PITA and it will break CV joints just tooling around in the paddock.

An open is not bad, just slow.

Cheers.

Tom Blaney
12-30-2004, 10:20 AM
I have decided that my posts aren't really worth much on this board anymore.

If anybody want's real straight information for someone who had built and won races, they can e-mail me at [email protected]

Have a nice time

[This message has been edited by Tom Blaney (edited December 30, 2004).]

Knestis
12-30-2004, 11:12 AM
There's just no way around the fact that a good dif is both expensive and valuable. I'm of the opinion that gears and traction are cheaper time found on the track than just about any other improvement, though - particularly a 'built' engine.

I'm a huge fan of clutch-type diffs and have ordered one of the Kaaz-built units for the Golf, from our friends at Bildon. I've also heard good things from people I trust about the OPM part.

A Quaife unit WILL spin an unloaded tire. If I were building a street car, I'd go that route but I want something a tad more positive for racing use.

K

gran racing
12-30-2004, 12:18 PM
Why do you say that Tom?? I think you'd find that many of us disagree with your statement about your posts not meaning much.

(Yes, I realize we all may have discussed this topic some time ago.)

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Dave Gran
NER ITB #13
'87 Honda Prelude si

JeffYoung
12-30-2004, 12:41 PM
I have a Quaiffe, since I have limited options for my car. Kirk is right, it will spin an unloaded tire. On smooth tracks this is not an issue. On bumpier ones, or when touching curbing, it can be.

apr67
12-30-2004, 01:03 PM
I've driven a welded dif in my own Rabbit GTI (since gone) and Chris Albins Golf.

I don't find that it breaks CV's (you just can't turn the steering wheel more than about half a turn in the paddock). I like it in the wet as well as the dry. In the wet, it stops front wheel lockup when one tire is in a puddle and the other isn't. Either both wheels lock, or neither.

If your choice is open, phantom grip, or welded then Welded is generally going to be the fastest.

ITA Racer
01-01-2005, 06:16 PM
Thanks for the replys everyone. I learned one one thing realy important from this post for shure. Build a safe and reliable car this year and spend my money ontrack time then add all the expensive gofast stuff latter.

zooracer
01-16-2005, 09:43 PM
Do not waste your money on a phantom grip. If you do, you are throwing money away. Instead send it to me and I will spend it.
I cannot stress this enough. I have one on my ITB car, as does my friend on his ITB swift. I got the stiffest springs (green), but this didnt make any difference. I honestly cannot tell the difference from an open diff.
I get inside wheelspin in some FOURTH gear corners! And I'm making about 85 ft lbs of torque.
Wait, save your money, and buy whatever the fast guys are running.
matt

seamus88
01-17-2005, 07:12 PM
Phantom Grips are also known to fail and take the entire trans and case with them.
http://homepage.mac.com/dgiessel/.Pictures...r/phantom_grip/ (http://homepage.mac.com/dgiessel/.Pictures/car/phantom_grip/)

[This message has been edited by seamus88 (edited January 17, 2005).]

Knestis
01-17-2005, 07:37 PM
AAAAH! It's the blob - run!

http://homepage.mac.com/dgiessel/.Pictures/car/phantom_grip/P7290427.JPG

That's just freakin' awful.

K

[This message has been edited by Knestis (edited January 17, 2005).]

grjones1
01-18-2005, 12:05 PM
ITA,
I've used the same Quaife since 1991 in my Fiesta (which still wins a few races). It cost $1200 + installation. But it works and it doesn't break, and it doesn't break other drive train components. It gets me through the Carousel at Summit as quick as anyone and I experience no inside wheel spin. In my humble estimation, it was money well spent.
GRJ

joeg
01-18-2005, 03:58 PM
I have seen similar metal shavings on the tranny magnet in my PG Transaxle.
However, my Quaife box is in the car, so I am not worried.

As for messes, nothing beat the times I exploded tranny cases on my Ice racer. Ugh!!

I bet that tranny in the pics still worked, at least to drive the car onto the trailer.

gsbaker
01-18-2005, 04:19 PM
Originally posted by Knestis:
AAAAH! It's the blob - run!

a.k.a. aluminum soup.

G

apr67
01-18-2005, 05:31 PM
Originally posted by grjones1:
ITA,
I've used the same Quaife since 1991 in my Fiesta (which still wins a few races). It cost $1200 + installation.


One thing to keep in mind when picking a diff, what works for a 90hp Fiesta may not work (long..) for a 200hp Wombat GT. And vice versa.

Alan

ITANorm
01-18-2005, 08:43 PM
People with FWD Wombat GT's just weld the spiders - right Alan? http://Forum.ImprovedTouring.com/it/wink.gif The ultimate "no slip" diff.

apr67
01-18-2005, 11:05 PM
Right.

Now with the Wombat R you have to use a viscous..

ShelbyRacer
01-19-2005, 12:07 AM
Originally posted by seamus88:
Phantom Grips are also known to fail and take the entire trans and case with them.
http://homepage.mac.com/dgiessel/.Pictures...r/phantom_grip/ (http://homepage.mac.com/dgiessel/.Pictures/car/phantom_grip/)

[This message has been edited by seamus88 (edited January 17, 2005).]

Only problem- the Phantom Grip didn't cause the failure. Someone didn't reinstall the diff pin properly, it walked, one end dropped, and viola!

Now, please do not think I'm saying the PG didn't contribute... with the heat and the shavings and little pieces floating around (glaven)...

It's just that I've seen that failure happen a few times (some even in person), and it has nothing to do with the diff (unless your diff design eliminates the pin, as some do...)



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Matt Green
"Ain't nothin' improved about Improved Touring..."

joeg
01-19-2005, 09:01 AM
Matt-I thought there was a picture in that "diff" gallery showing that the roll pin was still in place and intact.

spnkzss
01-19-2005, 09:57 AM
Originally posted by joeg:
Matt-I thought there was a picture in that "diff" gallery showing that the roll pin was still in place and intact.

But if you look through those pictures, you see that the pin snapped at the top. The picture showing the pin installed was from the bottom.

Besides excess heat build up, I don't know that the PG was the total cause. I'm also sure some of that damage inside was caused after the pin snapped. The PG is totally in tact.

racer_tim
01-19-2005, 05:24 PM
What type of box is this from? Honda?

Stay with the locker and that way you can save money instead of going to the gym. Just drive around the paddock making 90 degree turns. That's enough of a workout for anybody.

P.S. It's worse with slicks



------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

grjones1
01-20-2005, 06:40 PM
I'm a huge fan of clutch-type diffs and have ordered one of the Kaaz-built units for the Golf, from our friends at Bildon. I've also heard good things from people I trust about the OPM part.

K[/B]

K.
In the "Torsen" dialogue, you seemed to favor a Quaife-type diff and here you like clutches. Not trying to start an argument, I'm just confused.
G

grjones1
01-20-2005, 10:45 PM
Originally posted by apr67:

One thing to keep in mind when picking a diff, what works for a 90hp Fiesta may not work (long..) for a 200hp Wombat GT. And vice versa.

Alan

But Alan that's 90 hp with 120 ft/lbs of mid-range torque in a 1700-lb car. http://Forum.ImprovedTouring.com/it/wink.gif
And of course you are absolutely right.

G

[This message has been edited by grjones1 (edited January 20, 2005).]

[This message has been edited by grjones1 (edited January 20, 2005).]

Bildon
01-26-2005, 09:39 AM
grjones1 I'll speak for Kirk here and assume he was favoring the Torsen/Quaife only when the clutch type diffs were nearly impossible to find for VWs stateside. Now that we've recently picked up an affordable Mechanical LSD line here, it becomes the obvious choice.

You can read some Pro/Con info on our site.


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Bill Sulouff - Bildon Motorsport (http://www.bildon.com)
Volkswagen Racing Equipment

spnkzss
01-26-2005, 09:55 AM
Originally posted by Bildon:
grjones1 I'll speak for Kirk here and assume he was favoring the Torsen/Quaife only when the clutch type diffs were nearly impossible to find for VWs stateside. Now that we've recently picked up an affordable Mechanical LSD line here, it becomes the obvious choice.

You can read some Pro/Con info on our site.




You don't do anything with Honda's do you?

grjones1
01-27-2005, 09:10 PM
Originally posted by Bildon:
You can read some Pro/Con info on our site.




Thanks, Bill.
G

Knestis
01-28-2005, 12:26 AM
Originally posted by grjones1:
In the "Torsen" dialogue, you seemed to favor a Quaife-type diff and here you like clutches. Not trying to start an argument, I'm just confused.
G


Originally posted in the other forum by Knestis:
Gear-type torque biasing diffs are generally considered to be very durable and, in the kind of cars we deal with, reliable.


I don't think that's confusing at all. The original question there was, "Anybody have any real info on how long these things last?"

Further, it isn't any more contradictory that elsewhere, I've voiced the opinion that a welded diff - or spool, now for some FWD cars - isn't as horrible as some people say and are (gasp) a perfectly fine answer.

I actually had FOUR options available and I chose the KAAZ-manufactured unit that Bildon is carrying now. It has the best features for me, with this car, at this time. I might have opted for the OPM clutch pack, but I was a little concerned about delivery time.

Heck, if I were ONLY road racing, I would MOST likely have gone with the spool, and if I were building a street-practical HPDE car, I'd use an TB option - either the Peloquin or Quaiffe.

Then again, I'm one of those dreadful moral relativist types that you hear about on the talk shows, who tends to think critically about issues rather than pitching in with one set of idealogues or another...

K

[This message has been edited by Knestis (edited January 27, 2005).]