6MT, Quaife ATB center differential - interest?

Hello, i´m from Germany and have Legacy H6 Spec B , tuned with many NA stuff and also the drivetrain is upgraded. In front and rear Quaife ATB are working fine. Now i´m looking for a usefull upgrade for the center diff - there a some options from Cusco, but all clutch based or open - so not realy for daily use. So i wrote some lines to Quaife to ask for the opportunity of a center ATB. Now i have choice - as unique part it will cost 2500-3500£ or i find 10 other guys which like to have this part, then it will cost about 750£ per part. The center diff will fit to all 2.5gt-b from MY05 on, the original subaru partnumber is 38913AA111 (or 38913AA112). It would be nice to find some guys, which think that this part is a "have to have". Ingmar

Are there different options for front/rear torque bias? I have a DCCD diff so I am not in the market for this, but I ask anyway because I think that a rear bias would probably make the product more attractive to performance enthusiasts.

 

With 50/50 bias I would spin the front tires on hard launches, but now with 35/65 I spin the rears. It also tends to oversteer rather than understeer when accelerating out of corners.

Yes, i can image, that this piont will/can be important. The quaife diff has standard 50/50 split with no wheelspin, but can transfer torque free between front/rear if necessary. I think it will be also a great update for the normal viscous, this can just close and tranfer 50/50 all the time. With the Quaife the front wheels don´t want to spin, because the diff will transfer the power to rear. The 50/50 situation is just in normal situation, if there will be any sign of wheelspin the diff will transfer power to the side with grip - that can be evry variation between 99/1-1/99 (if zereo than the quaife will operate like a open one).

I am probably interested, a good quality Quaife center differential sounds like what I am looking for when I do my 6mt upgrade

I would be interested as well.

Btw, post it also on nasioc. There are many guys who run JDM non-DCCD 6MT boxes. I am almost certain the same part would fit across all non-DCCD 6MT transmissions. I have access to JDM part database so will check later.

Nice to read that there are some guys Yes - i will ask in the nasioc. Now we need just 7 other Subi.... I have a link where all tansmissions and MY are listed (only impreza).

For USDM/EDM/UK/ADM Legacy check this link under Manual transmission\Mt, transfer & extension and look for the partnumber for the center differential.

 

Ingmar

If you post on NASIOC, it will get shut down. They would consider it a group buy, and they don't allow that. I tried it once with a limited run of wheels.

 

iwsti.com would be a better choice - that site exists to serve owners, not just vendors.

^ +1 they shutdown the Spearco WRX TMIC Group Buy, its on http://www.3gwrx.com now.

 

They wouldn't even allow a link to the other site.

I tried in nasioc and will see what happens, it is no group buy - just looking for interests . Also i installed a thread in iwsti.com, but i don´t know if www.3gwrx.com will be the right place, because it is the 2th gerenation with the nonDCCD.

 

@lieutenantcolumbo

+1 means you want one?

@lieutenantcolumbo

+1 means you want one?

 

No, I have a 5EAT, just meant agreement w/ the above post.

Btw, I think default bias of 45:55 would be ideal (like Subaru's own 5EAT). Just add touch to the rear. With our nose heavy cars we need the front wheel to still do the work. But 50:50 would be still great.

 

Btw, the price quoted is in EUR or GBP? (pound symbol you used would suggest GBP, but you're in Germany).

Price is quoted in GBP, because that is what quaife told me.

@unclemat

quaife only make 50/50 split. I ask Torsen too, because at Torsen T3 diffs you can choose between 35/65 to 65/35 split, but like they told me, that they don´t do small quantity of diffs. I ask them which the minimum quantity is - answer will follow, but i think more than 10.....

Either way, a Quaife/Torsen type diff would be a major upgrade over the VC.

Yes it will be a great update, but it should know more than 3 people - we need another 7 .

Any idea where and who can be ask too that we will find enough people??

Post this on nasioc and elsewhere but do not indicate it is a group buy (it is not quite one yet anyway). Say, that if Quaife hears from sufficient number of people they will consider putting out such a product. Tell them to post in the thread and that you will forward the thread link to Quaife.

 

This product can be also of interest for owners of DCCD trannies, potentially. Not everyone wants to deal with DCCD controllers, wiring, etc.

I would be most interested in a 35F/65R split, or at least 40F/60R like the later DCCD centers, 50/50 is not that intriguing, but I would still prefer that to the stock electronic controlled thing, i bought a subaru because i don't trust electronics in my drivetrain, and i want to keep things that way.

@MAZdadaslo

Do you have DCCD swap in your LGT? Because you wrote that you prefered the stock electronic thing.

 

Yes, if you will have 65R/35F (or 61/39) in your DCCD, than you have it "open", that means with you will have no locking. You will have a rear biased thing, but is that what you want??

With the Quaife thing you will have best thing what is possible for the nonDCCD cars.

The DCCD will allow all combinations between 50/50 until 65/35 (R/F), nothing like the active center from the Mitsu EVO which allow evrything between 100/0 and 0/100.

The Quaife will give you mechanical and instantly and dynamicly evry torque split between 25/75 and 75/25 without any wheelspin necessary to work and no wheelspin will happen.

Your original VC unit has if it is locked just 50/50 split and needs a rpm difference between front and rear axle to work, because the silcon oil needs heat, so now you know why you have wheelspin at the front if you starting hard. So evry time torquetransfer is needed this vc needs rpm difference between front and rear - this is called reactive system. The Quaife (and all other torsen stuff) is proactive, it feels where the torque has to go before a rpm difference will happen. This will give you the most stable car and the best acceleration as possible.

So think about your installed system (VC), the system you can get (Quaife) and the system you probably wish or think it would be nice (dream).

You can get that torsen with your wished split from Torson, but there you need min. 1000 buyers not only 10.

 

BTW: the cars with torsen center (50/50) Hummer H1, Lancia Delta Integrale, Audi Quattro - Audi and Lancia have won many rallye runs

There are two incorrect statements here:

 

Yes, if you will have 65R/35F (or 61/39) in your DCCD, than you have it "open", that means with you will have no locking.

That's not true for the 2006+ STi center diffs. If you ignore the whole DCCD setup (e.g. set it to fully open) then the 2006+ diffs with the 41/59 torque split work like a Torsen T3. The mechanical diff itself provides a limited amount of lockup (up to 30% according to Subaru manuals) without any involvement from the DCCD clutches. DCCD provides up to 100% lockup of course.

 

The 2004-2005 STi center diffs with the 35/65 torque split were indeed open diffs with DCCD set to fully open.

 

The DCCD will allow all combinations between 50/50 until 65/35 (R/F), nothing like the active center from the Mitsu EVO which allow evrything between 100/0 and 0/100.

The Evo's ACD _cannot_ adjust the torque split like that. No car can that I've ever heard of. The Evo's actual mechanical center diff has a 50/50 torque split (every Evo ever built) and is open if paired with ACD. ACD adjusts lockup, like DCCD, except ACD uses messy hydraulics to actuate the clutch whereas DCCD uses an elegant electro-mechanical setup.

Post this on nasioc and elsewhere but do not indicate it is a group buy (it is not quite one yet anyway). Say, that if Quaife hears from sufficient number of people they will consider putting out such a product. Tell them to post in the thread and that you will forward the thread link to Quaife.

 

Good strategy.

@matt

i was near the truth . I didn´t know that the princip of DCCD center diff has changed from 2006 up - but it can only transfer the power between 41/69 and 50/50.

But please no discussion about DCCD . We need people for our Quaife diff .

 

@unclemat

i don´t think that it will be interesting for people which have DCCD in their cars, because it wont fit to the tranny.

 

Until now i have no chance to post at rexnet, maybe someone here is member there too and can discretly set a link to this forum?

It should fit DCCD tranny if the tail section is changed.

@unclemat

i think to complex for the DCCD thing, I can´t explain the changes which are needed for the DCCD tranny - so no ad possible.

[ame=http://www.youtube.com/watch?v=-xHraHtI4Qc]Have a look[/ame] Have a look what is possible with 3 times a torque sensing diff in a Subaru with the right driver skills. I think the center is no quaife, but one from PPG, because they make one for the WRX 5MT.