Found a front LSD!!

BADNEWS

BADNEWS

Member
Ok John Frana of http://www.franavehicles.com/ has seen Pat's (alltrac101) Front and Center diff combo. After looking at it he said he would be able to design a front helical (AKA Quaife type) lsd and our choice of either a 4 spider center that still uses the Viscous Coupling Unit or a Torsen center that will eliminate the center viscous coupling unit. The design is still not final till we place an order and then he'll invest his time.

His diffs look like this: (this is one from a neon SRT-4)

DSCF0105c.JPG


DSCF0112c.JPG


His background is off road buggy racing and he has made gear sets for truck pulling that has 3000 ft/lbs of torque.

Here is a video of him getting interviewed:

http://youtu.be/FeVKe834teg?hd=1

I know myself and Pat (alltrac101) are in for the initial group purchase to get this going.

We need 3 more people that would be interested in having this done. Price est is $2500 total for 2 differentials (front and center). IMHO this is a steal for such a low volume purchase. Maybe if we're lucky and get more than the 5 total guys the price will go down. But I'm just hoping for a couple of you to be interested in this so we can get this developed.

Anyone interested?
 
underscore

underscore

Well-known member
I'm interested, but not for at least 6 months. Also is it possible to get just his front/center? Lastly, has he actually opened one up and measured, or just glanced at it? Because I know a few companies have looked at doing this and said they can't without a tonne of specialized tools.
 
BADNEWS

BADNEWS

Member
underscore":2vl5vlzu said:
Also is it possible to get just his front/center?
Click to expand...

The front/center is one whole unit. That is why it has to be both. So either you get the front/center lsds together or nothing. He said he can't make it just a front and use the factory center from Toyota.

underscore":2vl5vlzu said:
Lastly, has he actually opened one up and measured, or just glanced at it? Because I know a few companies have looked at doing this and said they can't without a tonne of specialized tools.
Click to expand...

Yes he looked at it. He had one of Pat's (altrac101) transmissions. That is what he used to design his dogbox gear set for our transmissions. While designing the dogbox, Pat had John look into options for a front and center lsd. He stated that he took measurements of it and there is plenty of room to design something but he has to remake everything for it to work(nothing factory in the front/center can remain) except for the final drive ring gear that bolts to the center diff and the speedo gear. Like I said there is no final design because obviously he is not going to spend that kind of time into it until he knows that he can sell some units.
 
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Overtriped

New member
What would the rear diff include? Like the guy b4 me I would love to throw down but I can't afford it. Not for a while.
 
underscore

underscore

Well-known member
Sorry, I mean front/center as in one unit. To clarify:

rm2932":nx9pqat5 said:
underscore":nx9pqat5 said:
Also is it possible to get just his front/center?
Click to expand...

The front/center is one whole unit. That is why it has to be both. So either you get the front/center lsds together or nothing. He said he can't make it just a front and use the factory center from Toyota.
Click to expand...

rm2932":nx9pqat5 said:
Price est is $2500 total for 2 differentials (front and rear).
Click to expand...

So by front and rear do you mean front and center, or a front+center and rear?
 
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alltrac101

Member
Overtriped":30uaut42 said:
What would the rear diff include? Like the guy b4 me I would love to throw down but I can't afford it. Not for a while.
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No rear, this is for whats inside the transmission only....
 
athousandleaves

athousandleaves

New member
By Front and Center I imagine he's making the case that the front diff sits in (the left side of the center diff) and the viscous unit will remain in place?

I can't imagine this not breaking without some sort of slip allowance in there.

I would be interested pending the 'streetablilty' of the setup, I still want to be able to drive my car on the roads and take it to track days without having to trailer it there.
 
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temperacerguy

New member
I would be in. But I am not going to finance his development on it... Meaning I am not going to send in $2500, and wait/see if something comes out of it.

If he builds it, and it performs as expected without breaking, I would buy it.
 
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lumbercis

Moderator
^Usually in these situations a partial deposit is put down (a quarter or half) to finance materials and then the balance is due once the unit is done. That would be good info to know for this GB.

If you're waiting for a small shop to bear 100% of the material and development cost on a run of 5 and then hope to sell them after they're done you'll be waiting forever.

It is a ton of money though, so I understand your caution.
 
BADNEWS

BADNEWS

Member
I was just seeing the interest in this (which is small). If people are interested, I'm willing to front my whole $2500 so others don't need to pay as much. But I'm sure we would need some sort of deposit. We would need something to bind people to the purchase. Otherwise, all we have is their word which they can back out on too easily.
 
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lumbercis

Moderator
....our choice of either a 4 spider center that still uses the Viscous Coupling Unit or a Torsen center that will eliminate the center viscous coupling unit.
Click to expand...

Which one of these would hold up better to drag launches?

I did a little reading on the dsm forums and it seems like they use a 4-spider (or weld the center diff) and keep the VC unit (someone correct me if I'm wrong)?

Pat, what have you broken in the front? I'd like to hear more opinions on the relative benefits of the VC vs torsen.
 
BADNEWS

BADNEWS

Member
lumbercis":23q2axef said:
Which one of these would hold up better to drag launches?

I did a little reading on the dsm forums and it seems like they use a 4-spider (or weld the center diff) and keep the VC unit (someone correct me if I'm wrong)?
Click to expand...

I've been doing research too. Quiafe only had issues with the talon/eclipse center lsd. I guess the problem was available space. The talon/eclipse Quiafe unit still hooks up and utilizes the factory viscous unit. They make units for Evo's with no problems.

http://forums.evolutionm.net/7463746-post14.html

Here is a 4 spider DSM diff on youtube that broke the case just like a Quaife:
http://youtu.be/P5Ib6wDKeMw

Effective June 15, 2001, Quaife America will no longer replace broken differential housings on 76.309.155 (9B1) Center Differentials at no charge.

We have found that, due to design constraints of the transmission, the original equipment third gear that meshes with the center diff housing is prone to failure under extreme loading in modified vehicles. When this gear fails, it may cause the gear teeth ground on the Quaife housing to break, necessitating replacement. The Quaife Center Differential made for the Mitsubishi Eclipse/Talon AWD Turbo models are built from very high strength, case hardened material. However, even the superior construction of the Quaife Differential may fail under these situations, under no fault of the Quaife product.

Since this type of failure is not a fault of the Quaife product, we will not replace a broken housing that is due to this type of occurrence free of charge under the Quaife lifetime warranty policy. We will, however, replace the housings at a specially arranged price that covers our manufacturing costs.

All other components of this differential remain fully covered under our limited lifetime warranty.

For more info, contact our tech department at (949) 240-4000.

lumbercis":23q2axef said:
I did a little reading on the dsm forums and it seems like they use a 4-spider (or weld the center diff) and keep the VC unit (someone correct me if I'm wrong)?

Pat, what have you broken in the front? I'd like to hear more opinions on the relative benefits of the VC vs torsen.
Click to expand...

I just talked with Pat on the phone yesterday. He has never had any issues with the front or center differentials. And he told me when John Frana was looking at our diffs design, he felt there was plenty of room for a high strength piece.

Now if you watch slow motion drag launches you can tell which cars run the 4 spider w/ factory VC compared to a welded center. ones with the VC spin the front tires about 3 times for every time the rears rotate. Welded diffs obviously rotate at the same speed.

But I'm not welding my center diff. Don't want to do that to my car.
 
BADNEWS

BADNEWS

Member
Spectra1":18uo9fst said:
Im in depending on how much of a deposit would be needed.
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I'll call John this week and get more details on what he would want for a down payment and his guess on a time frame.
 
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ALLensTRAC

New member
I am still waiting to hear what Quaiffe says but I am somewhat interested. I will have to liquidate some stuff to cover 2500 though. This could be done by the 6 month to 1 year timeframe that Pat said. I guess we could start an interest list :shrug:

On another note Temperacerguy: Welcome back!!!
 
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tjdouble07

New member
Man, sometimes it sucks being married... :p I really want to commit to this, although at this moment I can't. In a few months I will see if I can justify this to my wife as to why I "need" to take this out of our tax return... Now if this was a bullet-proof rear diff, I would find a way...
 
BADNEWS

BADNEWS

Member
tjdouble07":17dkxij0 said:
Man, sometimes it sucks being married... :p I really want to commit to this, although at this moment I can't. In a few months I will see if I can justify this to my wife as to why I "need" to take this out of our tax return... Now if this was a bullet-proof rear diff, I would find a way...
Click to expand...

I just took the leap and Ordered a Cusco Rear. Probably won't get it for 2 more months. Maybe if this goes through you'll get a front and order yourself a Cusco.
 
R

RedCelicaTRD

Moderator
tjdouble07":1ba2ga05 said:
Man, sometimes it sucks being married... :p I really want to commit to this, although at this moment I can't. In a few months I will see if I can justify this to my wife as to why I "need" to take this out of our tax return... Now if this was a bullet-proof rear diff, I would find a way...
Click to expand...

Put on your big-boy pants and make it happen!
 
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