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juxsa
01-05-2011, 08:39 AM
Just wanted to drop a quick note about the center diff mod for people who are on the fence about doing it. It really is awesome!!! This is how the car should have come from the factory. There is still a little understeer (I dont know how much further in front of the wheels the could have put the engine) but it is greatly reduced and performs much more like a sports sedan should. You wont notice much of a difference at low speeds but when you punch it as you exit a corner the car actually goes where you want to go instead of understeering like crazy. Go to the junk yards or look on the forums and see if you can find a diff and send it off to get modded. Both the 1 piece and 2 piece diffs are interchangeable from the 5 speed A4 B5s and B6s. I know this because my 01 came with the newer 1 piece and the diff I installed was an older 2 piece. It bolted right in.

If your thinking about putting a bigger turbo in, do this mod first. If your thinking about putting bigger sway bars in, do this mod first. If your thinking about beefing up your suspension, do this mod first!!!

If your car is still stock then I would likely put a bigger intercooler in, swap the plugs, and chip it first, but after that the next mod should be swapping out the diffs.

somebody5788
01-05-2011, 09:00 AM
Just wanted to drop a quick note about the center diff mod for people who are on the fence about doing it. It really is awesome!!! This is how the car should have come from the factory. There is still a little understeer (I dont know how much further in front of the wheels the could have put the engine) but it is greatly reduced and performs much more like a sports sedan should. You wont notice much of a difference at low speeds but when you punch it as you exit a corner the car actually goes where you want to go instead of understeering like crazy. Go to the junk yards or look on the forums and see if you can find a diff and send it off to get modded. Both the 1 piece and 2 piece diffs are interchangeable from the 5 speed A4 B5s and B6s. I know this because my 01 came with the newer 1 piece and the diff I installed was an older 2 piece. It bolted right in.

If your thinking about putting a bigger turbo in, do this mod first. If your thinking about putting bigger sway bars in, do this mod first. If your thinking about beefing up your suspension, do this mod first!!!

If your car is still stock then I would likely put a bigger intercooler in, swap the plugs, and chip it first, but after that the next mod should be swapping out the diffs.

I did this mod last week hehe. I like it, for the most part the car feels stock but when you really push it things are more predictable.

juxsa
01-05-2011, 09:22 AM
I remember the first time I pushed the car hard, and this was before I knew about how much of a FWD bias the car had, I damn near slid in to a curb because of the amount of understeer. Not nearly as much of a problem now

somebody5788
01-05-2011, 09:29 AM
I remember the first time I pushed the car hard, and this was before I knew about how much of a FWD bias the car had, I damn near slid in to a curb because of the amount of understeer. Not nearly as much of a problem now

It's not mechanically FWD bias at all. But it can feel like it...

Dubluva
01-14-2011, 06:38 AM
Forgive my ignorance, but where can I get more details/DIY on the center diff mod? I didn't see anything in the DIY section.

somebody5788
01-14-2011, 06:46 AM
Forgive my ignorance, but where can I get more details/DIY on the center diff mod? I didn't see anything in the DIY section.

JHM and STaSIS offer one. The DIY'er can buy some washers for $50

and to add to the review. THIS IS AMAZING IN THE SNOW!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

juxsa
01-14-2011, 01:19 PM
And the Rain!!!

somebody5788
01-14-2011, 01:51 PM
It was worth every penny! Wait it was free for me hehehe. I know people

FNK
01-14-2011, 02:56 PM
I've read it's only for manual cars... right?

sean1.8t
01-14-2011, 03:07 PM
i've had those washers sitting on my nightstand for far too long! one day i will get to this

A4Rob
01-14-2011, 03:12 PM
Well funny you mention this... I am doing the mod tonight. I have a set of washers and an extra Diff. I built it last weekend and plan to put it in tonight. We also got 4" of fresh snow here in Mpls.

All ready to go in!

http://img.photobucket.com/albums/v468/a4robm/CIMG0127.jpg

034Motorsport
01-14-2011, 03:15 PM
Combined with an upgraded rear sway bar and some rear spherical sway bar end links, the 4:1 diff mod is one of the best things you can do for these cars. Plenty of lift throttle oversteer, far easier to modulate the trajectory and rotation of the car.

somebody5788
01-14-2011, 03:36 PM
All I need is my rear sway. Got the suspension and the dif already. Just too much fun

Kronic Budz
01-14-2011, 03:56 PM
this mod pretty much gives the car more oversteer and less understeer? i would think its better to have more power going to the part of the car with more weight..?

and how would this setup compare in rain and snow? i thought fwd biased is better in these conditions.

J Ozzie
01-14-2011, 04:12 PM
Humm, is it really worth it? I mean in the wet if i take a corner wide and then punch it i can kick the back end of the audi out easy or in the snow! I swear its more rear wheel! I guess this would be good for all you Track Guru's.

somebody5788
01-14-2011, 08:20 PM
Guys... it's neither FWD or RWD bias... It's a torque sensing dif. It sends torque to the axle with the most grip. This mod increases the ratio that it can send to either side. Understeer = loss of traction. When the front wheels are losing traction the rears are just following. This mod doesn't necessarily make it drift everywhere but rather makes it easier to kick out when you want to instead of just understeering all the time.

FNK
01-15-2011, 08:04 AM
What is the difference between Automatic and Manual center diff? It must be the same... right? Both are 5 speed... I want this mod!

Kronic Budz
01-15-2011, 10:45 AM
Guys... it's neither FWD or RWD bias... It's a torque sensing dif. It sends torque to the axle with the most grip. This mod increases the ratio that it can send to either side. Understeer = loss of traction. When the front wheels are losing traction the rears are just following. This mod doesn't necessarily make it drift everywhere but rather makes it easier to kick out when you want to instead of just understeering all the time.

sweet, gotta get me one of those :)

OLiK
01-15-2011, 12:57 PM
is there a write up for this?!?!?!

jaystacks
01-15-2011, 02:06 PM
+1 this is something i may want to do to my 2.8

somebody5788
01-15-2011, 02:16 PM
I'm not sure why the auto's have a different dif but all I've ever heard is that it's not compatible with the auto's.

http://forums.vwvortex.com/showthread.php?4963427-FS-4-1-Center-Diff-Mod-Washers-like-Statis

I got my washers from him. He's legit

A4Rob
01-15-2011, 03:00 PM
is there a write up for this?!?!?!

http://audizine.com/forum/showthread.php/199202-Center-Diff-Washer-mod-for-20-80-TBR

FNK
01-15-2011, 06:08 PM
I'm not sure why the auto's have a different dif but all I've ever heard is that it's not compatible with the auto's.

Alright thank!

flynnr
01-16-2011, 08:41 AM
Well funny you mention this... I am doing the mod tonight. I have a set of washers and an extra Diff. I built it last weekend and plan to put it in tonight. We also got 4" of fresh snow here in Mpls.

All ready to go in!

http://img.photobucket.com/albums/v468/a4robm/CIMG0127.jpg
Hows it feel? Do you recommebd buying another diff to do this on?

SunyaT23
01-16-2011, 08:49 AM
I was thinking about getting this for my car, Does it give the car a more grip feel through turns? and how much better is it in the snow casuse seen someone said that it was AMAZING! haha But can I get some more feedback on that?

EuroDriven
01-16-2011, 11:03 PM
Well funny you mention this... I am doing the mod tonight. I have a set of washers and an extra Diff. I built it last weekend and plan to put it in tonight. We also got 4" of fresh snow here in Mpls.

All ready to go in!

Good to see my parts are going to a good use!

BASARAB
01-16-2011, 11:15 PM
Omg, mods never end for these Audi's. And about every mod people say that its the best bang for your buk. My head hurts, I am lost in deciding what I am going to do next haha

juxsa
01-17-2011, 10:55 AM
Well since your already chipped and have SMFW and clutch I would do the Centerdiff then what ever else from then on. The 4:1 diff is how this car should have come form the factory


Omg, mods never end for these Audi's. And about every mod people say that its the best bang for your buk. My head hurts, I am lost in deciding what I am going to do next haha

Ketamine1
01-17-2011, 11:24 AM
I was thinking about getting this for my car, Does it give the car a more grip feel through turns? and how much better is it in the snow casuse seen someone said that it was AMAZING! haha But can I get some more feedback on that?
This is by far one of the most misunderstood mods in the history of AWD vehicles. It does not do anything, unless ur power on and driving at 99% of the limits of adhesion. It does not change the normal 50-50 split, and will not be noticed under normal driving. This mod will allow u 2 put down a little more power b4 u spin the inside front and allow a slight bit more throttle steer. Just remember when ur rear tires start 2 spin the diff will then send the power back 2 the fronts. Don't think ur gonna start Tokyo drifiting around turns. While it is a good mod for HPDE's and stuff, it is really unnecesary for normal driving.

somebody5788
01-17-2011, 12:01 PM
This is by far one of the most misunderstood mods in the history of AWD vehicles. It does not do anything, unless ur power on and driving at 99% of the limits of adhesion. It does not change the normal 50-50 split, and will not be noticed under normal driving. This mod will allow u 2 put down a little more power b4 u spin the inside front and allow a slight bit more throttle steer. Just remember when ur rear tires start 2 spin the diff will then send the power back 2 the fronts. Don't think ur gonna start Tokyo drifiting around turns. While it is a good mod for HPDE's and stuff, it is really unnecesary for normal driving.

This is all true. Though it will make it easier to make the car more tail happy.

juxsa
01-17-2011, 08:27 PM
Well I can tell ya that when I gun it around a corner, understeer is hardly a problem and that rear end likes to kick out. It really does make the car more predictable.

Shhmaudi
01-17-2011, 08:52 PM
Anyone in san diego want to get together and do this?

Finneid90
02-02-2011, 02:07 PM
Does a facelift centerdiff bolt on to a pre-facelift transmission?

somebody5788
02-02-2011, 03:42 PM
Does a facelift centerdiff bolt on to a pre-facelift transmission?

Ya as long as you get the housing as well.

Finneid90
02-03-2011, 08:04 AM
Thanks!
How does the car act before/after install? (I see you have done the washer mod)

somebody5788
02-03-2011, 09:11 AM
This has all been covered in this thread hehe

belinko
02-03-2011, 10:19 AM
Got the JHM center diff last year. In conjunction with stiff suspension and anti-sway bars the car becomes very neutral. No more plowing through corners, under-steer is almost completely eliminated. Induced over-steer is now possible. In some cases the car behaves like a rwd car. Daily driving has not been an issue, there can be some shudder from diff at full lock in parking areas, due to the friction differences of the materials in the diffs. All in all its a great mod, but the benefits are seen at the track or Autox or sliding around corners on the street. Oh yeah, you can do dognuts in a wet or snowy parking lot finally without having 400hp. $.02

somebody5788
02-03-2011, 10:31 AM
Got the JHM center diff last year. In conjunction with stiff suspension and anti-sway bars the car becomes very neutral. No more plowing through corners, under-steer is almost completely eliminated. Induced over-steer is now possible. In some cases the car behaves like a rwd car. Daily driving has not been an issue, there can be some shudder from diff at full lock in parking areas, due to the friction differences of the materials in the diffs. All in all its a great mod, but the benefits are seen at the track or Autox or sliding around corners on the street. Oh yeah, you can do dognuts in a wet or snowy parking lot finally without having 400hp. $.02

??????????

For real? I've always done donuts in wet ones. and at 250-270hp you should actually be able to on a dry parking lot.

belinko
02-03-2011, 10:40 AM
I'm thinking AWD donuts on dry asphalt, needs some serious power. I would think with your power levels you should be able to do them in the dry?

With OEM power levels and a 4:1 diff it's now possible in the wet. That's all.

somebody5788
02-03-2011, 10:43 AM
I'm thinking AWD donuts on dry asphalt, needs some serious power. I would think with your power levels you should be able to do them in the dry?

With OEM power levels and a 4:1 diff it's now possible in the wet. That's all.

Bone stock hp, 235/40/18 tires, just a decent clutch and a wet parking lot.

http://www.youtube.com/watch?v=jmnxums8l4Q

spindoctor
02-03-2011, 07:58 PM
Looks fun. I wonder what would the effect be like with a torque biasing rear diff.

A quick google search says quaife makes em for our car :D

http://www.quaife.co.uk/shop/products/qdf4q-0

PT102900
08-13-2014, 01:32 AM
Combined with an upgraded rear sway bar and some rear spherical sway bar end links, the 4:1 diff mod is one of the best things you can do for these cars. Plenty of lift throttle oversteer, far easier to modulate the trajectory and rotation of the car.

For a audi A4 B6 2.5 diesel 180 HP , does it worth to put on one of this 4:1 dif instead of 2:1 original ( 01E-409-751-F ) ?

SilentAngle
10-12-2014, 11:31 PM
For a audi A4 B6 2.5 diesel 180 HP , does it worth to put on one of this 4:1 dif instead of 2:1 original ( 01E-409-751-F ) ?

Depends how hard you drive. Should make a big difference in the snow.

juxsa
10-13-2014, 04:32 AM
Looks fun. I wonder what would the effect be like with a torque biasing rear diff.

A quick google search says quaife makes em for our car :D

http://www.quaife.co.uk/shop/products/qdf4q-0

And apparantly you can stick a rear LSD from a 944 in our car. Depending on what you would pay for a 944 diff and the cost of rebuilding it I could see that being waaaaaaaaaaaaaaaay cheaper

vtraudt
06-20-2018, 05:23 AM
Does someone have a source where to get the required parts for DIY?

Seerlah
06-20-2018, 10:08 PM
PM sent

GOODBYNAAIR
06-21-2018, 07:48 AM
PM sent

Mitch has been lurking [cool] whats up man

Fender0122
07-03-2018, 03:25 PM
And apparantly you can stick a rear LSD from a 944 in our car. Depending on what you would pay for a 944 diff and the cost of rebuilding it I could see that being waaaaaaaaaaaaaaaay cheaper

Probably a good idea to look into a LSD for the rear. I enjoyed my diff mod while it lasted, but inside tire spin on the rear was definitely more noticeable in the rain with the mod. Another good idea is to not accidentally put 80w gear oil instead of the recommended 75w when you live in a northern climate. 0 Degrees out and it shot the washers out the side of the case. Still wouldn't mind tracking down another diff and doing it again.

Ephry73
07-03-2018, 04:17 PM
Probably a good idea to look into a LSD for the rear. I enjoyed my diff mod while it lasted, but inside tire spin on the rear was definitely more noticeable in the rain with the mod. Another good idea is to not accidentally put 80w gear oil instead of the recommended 75w when you live in a northern climate. 0 Degrees out and it shot the washers out the side of the case. Still wouldn't mind tracking down another diff and doing it again.

Iíll have an 01A diff for sale soon and not expensive at all if youíre interested in a core to mod

E


Sent from my iPhone using Tapatalk

Seerlah
07-04-2018, 04:38 AM
Mitch has been lurking [cool] whats up man

Didn't even notice this reply. Nothing much Mark, same ol' same ol'. As far as the car goes, I'll update my build thread soon. Need to get finished with something first.

If you will be making it to Waterfest this year, I'll see you there (as of now, I def plan on making it). Crack some beers at the Audizine tent (this race park permits alcohol as long as you follow the rules, vs the old location where it was prohibited). I keep a cooler filled with beer at meets.

GOODBYNAAIR
07-04-2018, 06:41 PM
Didn't even notice this reply. Nothing much Mark, same ol' same ol'. As far as the car goes, I'll update my build thread soon. Need to get finished with something first.

If you will be making it to Waterfest this year, I'll see you there (as of now, I def plan on making it). Crack some beers at the Audizine tent (this race park permits alcohol as long as you follow the rules, vs the old location where it was prohibited). I keep a cooler filled with beer at meets.

Nice!! not sure if I will make it life is crazy now with a 10 month old baby. Awesome but crazy, if I some how make i'll let you know! Cheers good sir!