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WestfarmRacing
03-08-2013, 12:29 PM
Taking up the project of turning the widebody S4 into a "real" RS4

Car: S4 ´00 complete widebody, rs4 exterior and interior.
The only major thing missing was the engine, it still has a stage 2 S4 engine.

Got hold of an RS4 engine (AZR) with a blown rod bearing, which also resulted in a piston hitting an intake valve.

Going to rebuild it with rods, valve train and all that.

Havent really decided on turbos yet, but leaning into rs6´s

Stripped the engine today and it looks like the crank only needs polishing :)



Ikea style
http://i1135.photobucket.com/albums/m622/WestfarmRacing/motor1_zpsa3edc228.jpg

The car

http://i1135.photobucket.com/albums/m622/WestfarmRacing/DSC_0770.jpg
http://i1135.photobucket.com/albums/m622/WestfarmRacing/DSC_0771.jpg
http://i1135.photobucket.com/albums/m622/WestfarmRacing/DSC_0763.jpg

rtl5009
03-08-2013, 12:31 PM
Nice!

S4 00 2.7
03-08-2013, 12:40 PM
Nice build. I love the RS4 in black.

A3TOXX
03-08-2013, 12:43 PM
Nice!

Street Nasty
03-08-2013, 12:56 PM
How much money do you save replicating versus buying an rs4?

WestfarmRacing
03-08-2013, 01:13 PM
How much money do you save replicating versus buying an rs4?

Nothing really. The guy i bought it from did the body/interior swap, used a shitload of money on it ( something like 30k$). Think it was a small project for him that got out of hand.. I just picked it up for a nice price in a bad economy :)

034Motorsport
03-08-2013, 01:20 PM
Nothing really. The guy i bought it from did the body/interior swap, used a shitload of money on it ( something like 30k$). Think it was a small project for him that got out of hand.. I just picked it up for a nice price in a bad economy :)

That's the way to do it! Capitalize on other's misfortune! =)

Car looks great, going to be an awesome project. Hope you're stepping up to 3.0L if you're getting new pistons, etc?

WestfarmRacing
03-08-2013, 01:52 PM
That's the way to do it! Capitalize on other's misfortune! =)

Car looks great, going to be an awesome project. Hope you're stepping up to 3.0L if you're getting new pistons, etc?

haha that another way seeing it =)

Tnx. Think i will stay with 2.7, its just one piston that needs to be replaced. Another thing is i like the "sting" of the 2.7 =)

And it gets a lot more expensive as soon as we talk 3.0..

Street Nasty
03-08-2013, 02:22 PM
Nice pickup indeed, running out of money projects are the best to pick up. Car definitely looks great, but without the roof rails it looks kind of like an A3.

WestfarmRacing
03-08-2013, 02:34 PM
Rails on its way, dont you worry!

slowrideBC
03-08-2013, 06:21 PM
That's the way to do it! Capitalize on other's misfortune! =)

Car looks great, going to be an awesome project. Hope you're stepping up to 3.0L if you're getting new pistons, etc?

why do you always chime in and advise ppl to a 3 L? why bore out the block and take away material just for 500rpm quicker spool time? For a real HP build I would stay stock bore and toss some 2.8 heads on. 3L suck

nice car OP...Im gonna be sub'd to this build....always such cool builds coming from Norway/...

WestfarmRacing
03-09-2013, 02:21 AM
why do you always chime in and advise ppl to a 3 L? why bore out the block and take away material just for 500rpm quicker spool time? For a real HP build I would stay stock bore and toss some 2.8 heads on. 3L suck

nice car OP...Im gonna be sub'd to this build....always such cool builds coming from Norway/...

Tnx. Will stay 2.7, and keep the heads. These are Coscast Rs4 heads, wouldnt change them for 2.8 :)

Bische
03-09-2013, 03:45 AM
100% avundsjuk på den bilen [:)]

Har du någon som mappar den?

WestfarmRacing
03-10-2013, 12:49 AM
100% avundsjuk på den bilen [:)]

Har du någon som mappar den?

The mapping will be done here. Setting up a basemap, run some logs and take help from the tuner in Germany

Bische
03-10-2013, 07:58 AM
The mapping will be done here. Setting up a basemap, run some logs and take help from the tuner in Germany

Alright, I hope everything goes well for you!

WestfarmRacing
04-02-2013, 07:46 AM
The crank is sent away for polishing, so meanwhile I fitted the roof rails.
Not very stoked about drilling the roof, but it had to be done either way..

(Yeah, I know the photo is up side down)

http://i1135.photobucket.com/albums/m622/WestfarmRacing/2013-03-23172108_zpsffb2ee82.jpg

WestfarmRacing
06-18-2014, 01:23 AM
Finally something is happening here, the Project got on hold between other Projects.. Just purchased a crank for the rs4 engine, the original one was Beyond salvation. Cleaned all engine parts, and going to Rosten today to get some Nice internals for it :)

Also decided to og With rs6r turbos [up]

http://i1135.photobucket.com/albums/m622/WestfarmRacing/10441211_330001867153226_6485265312102047591_n_zps 358bf752.jpg

achb5
06-18-2014, 10:16 PM
Nice build, what's the deal with the roof of your house?


Sent from middle of nowhere

WestfarmRacing
06-18-2014, 11:44 PM
Thanks. You mean the grass roof? Thats not my house, it's some restaurant in Norway [:)]

achb5
06-19-2014, 07:32 AM
Love the photo


Sent from middle of nowhere

S4 00 2.7
06-19-2014, 08:31 AM
Pictures of roof rails on?

WestfarmRacing
06-19-2014, 02:41 PM
See if I can snap one, the car is on the lift for now :) Polished the crank and began the engine assembly today, always fun putting new stuff together. Parts delivered by Rosten performance of course [up]

http://i1135.photobucket.com/albums/m622/WestfarmRacing/Mobile%20Uploads/20140619_204347_zpsqtb8my89.jpg

http://i1135.photobucket.com/albums/m622/WestfarmRacing/Mobile%20Uploads/20140619_225426_zpssfflmxpy.jpg

http://i1135.photobucket.com/albums/m622/WestfarmRacing/Mobile%20Uploads/20140619_225435_zpsa1djum6u.jpg

http://i1135.photobucket.com/albums/m622/WestfarmRacing/Mobile%20Uploads/20140619_225458_zpshtvgrpmt.jpg

landfill
06-19-2014, 07:18 PM
Great widebody project good luck.

Dino V
06-20-2014, 11:53 AM
beautiful!

pipe7284
06-20-2014, 01:04 PM
love this project!!! I want widebody.

WestfarmRacing
06-22-2014, 01:25 AM
Thanks. Hope it will be as i expected, engine build is in progress. Also got a set of 365mm rs6 brakes for it :)

http://img.tapatalk.com/d/14/06/22/9e6a2utu.jpg
http://img.tapatalk.com/d/14/06/22/arava8eg.jpg

WestfarmRacing
06-22-2014, 01:45 AM
http://img.tapatalk.com/d/14/06/22/y9u5e5as.jpg

spindoctor
06-22-2014, 05:55 AM
Nice set of wheels. What are they(specs)?

WestfarmRacing
06-22-2014, 06:41 AM
It says zito and a-tech. It's 10"x18 et15

Skickat från min GT-I9505 via Tapatalk

spindoctor
06-22-2014, 06:07 PM
Did you use wobble bolts or get it custom drilled? Couldn't find 5 x 112 at ultralite's website and Zito's

WestfarmRacing
06-23-2014, 01:50 AM
Did you use wobble bolts or get it custom drilled? Couldn't find 5 x 112 at ultralite's website and Zito's

They are custom made 5x112 in some sort of group-order a couple of years ago. At that time they were ordered for widebody s2 race cars.

But if you ask them, I Guess they could make them again but maybe you need to order a few

In regular 8,5" you can buy zito in 5x112 over here, I have a set of 8,5x18 5/112 also

WestfarmRacing
06-28-2014, 01:48 PM
Got the block build finished, so time to start some work on the heads. Grinded and assembled the passanger side today, was a real pita to get the small intake valves in, had to fab myself up a valve spring compression tool. It worked really well :) http://img.tapatalk.com/d/14/06/29/ava2aba3.jpg
http://img.tapatalk.com/d/14/06/29/ysajy2as.jpg
http://img.tapatalk.com/d/14/06/29/qare5a7a.jpg
http://img.tapatalk.com/d/14/06/29/evugute8.jpg

tosh2.7
06-28-2014, 02:14 PM
mmmmm beer

WestfarmRacing
06-28-2014, 02:33 PM
Arrrghhhghrrhhh... hehe

ilyafil
06-28-2014, 03:54 PM
Coming together nicely! Mad props. [:d]

richmonds4
06-28-2014, 06:53 PM
Nice build and car !
Be sure you replace and torque the crank bolt to spec or you will blow your engine !
It looks old in the pics

WestfarmRacing
06-29-2014, 01:08 AM
Thanks. Good you noticed that, just using it to crank the engine now. Of course a new one is going in there. Did you know rs4 has an extra friction shim at the lower crank gear? Does s4 have it too?

kwazimodo
06-29-2014, 04:36 AM
They dont, but its just to add one if youre in there doing something.

WestfarmRacing
06-29-2014, 09:39 AM
Its growing [emoji123]

http://img.tapatalk.com/d/14/06/30/3a3eseja.jpg

richmonds4
06-29-2014, 02:14 PM
S4 does have a friction shim 1 between the pulley and crank shaft .
Does the rs4 have 2
They make upgraded ones

kwazimodo
06-29-2014, 03:37 PM
S4 does have a friction shim 1 between the pulley and crank shaft .
Does the rs4 have 2
They make upgraded ones

None of the s4s ive taken apart had the shim, but I always put it back with a shim. RS4 only has one.

okkim
06-29-2014, 07:05 PM
That is true, only RS4 has the shim. ETKA also shows shim only for the RS4. I also have opened a lots of S4 and RS4 motors.

WestfarmRacing
06-29-2014, 11:46 PM
Couldn't remember seeing them on regular 2.7 either.

Heavy Winter
06-30-2014, 08:28 PM
Wow!

Very nice.

WestfarmRacing
07-01-2014, 01:06 PM
Pic whoring as the build goes on. Got hold of a pair oem rs6 turbos, so thats the route im going for. Ordered custom 16psi actuators that im going to fit somehow. Think this setup is going to be nice on a street rs4 :) Its quite tricky to get the rs6's modded but we'll get there =)

http://img.tapatalk.com/d/14/07/02/eparugem.jpg
http://img.tapatalk.com/d/14/07/02/jytehyzy.jpg
http://img.tapatalk.com/d/14/07/02/y5avupuj.jpg
http://img.tapatalk.com/d/14/07/02/abebema3.jpg

WestfarmRacing
07-13-2014, 10:02 AM
Got the old f....er out, a lot of work left to do..

http://img.tapatalk.com/d/14/07/14/a8asu4at.jpg

WestfarmRacing
07-15-2014, 05:08 AM
Chopping the rs6's up to modify. It's not easy, but doable if you take your time..
http://img.tapatalk.com/d/14/07/15/esu4yger.jpg

Also got some big ic's, noname from germany. We'll see how the iat's will be with those. Most of the year it's cold here, so dont think that will be a huge problem.. Also got a pair of ER shrouds as a gift from rosten performance. Thanks =)

http://img.tapatalk.com/d/14/07/15/yty3ubut.jpg

jibberjive
07-15-2014, 06:02 AM
Are those RS4 specific IC's? Or do you know if they fit on narrow body S4's as well?

hibiscusS4
07-15-2014, 06:19 AM
holly hell are those big side mounts!

RedB5S4
07-15-2014, 06:35 AM
Are those RS4 specific IC's? Or do you know if they fit on narrow body S4's as well?

He did say that they're nonames... Can't imagine that they would be specific to the RS4 but could be me. They look comparable in size to any SMIC's that I've seen for S4s from looking at the pics.


holly hell are those big side mounts!

S4 side-mounts are huge when you see them in person. I swore up and down a wall that the SRMs would never fit in my car but they did. You have to relocate the O2 condenser back a little bit and trim the rad support so the top tank doesn't contact it, but they fit.

WestfarmRacing
07-15-2014, 07:51 AM
They are for the rs4, you can order them for s4 and they look a bit different. Think they are just a little bitt smaller. Heres a pic besides an oem s4 ic

http://img.tapatalk.com/d/14/07/15/9ugazyvy.jpg

WestfarmRacing
07-15-2014, 02:14 PM
The rs6 turbo mod goes on, it's a bit of work but i'm really close now. Rewelded comp housings and fabing up brackets and rods for the new 16psi actuators. (Apologizes if i have bad spelling) =)

http://img.tapatalk.com/d/14/07/16/y4u7evum.jpg
http://img.tapatalk.com/d/14/07/16/4adu3equ.jpg
http://img.tapatalk.com/d/14/07/16/6y8adage.jpg

WestfarmRacing
07-18-2014, 12:54 PM
Finally it looks like its getting closer.. so much stuff on these, used to building a4's and 5-cyl cars =)

http://img.tapatalk.com/d/14/07/19/na3ubusa.jpg

WestfarmRacing
07-19-2014, 10:19 AM
http://img.tapatalk.com/d/14/07/20/yrumu5e2.jpg

WestfarmRacing
07-19-2014, 04:15 PM
Fabbed up some engine mounts in POM plastic, im suspecting it will vibrate a lot, but will give it a try at least.. any experiences here with stiff mounts on these v6's?
http://img.tapatalk.com/d/14/07/20/jyzezugu.jpg

Dr.d
07-19-2014, 05:01 PM
Stiff mounts on the v6s aren't bad at all IMO. They are pretty smooth running motors. I've heard on the 4 & 5 cyl cars they are pretty bad though.

JanAimar
07-19-2014, 06:00 PM
Jävlar !
Cool build. Just dailydriver or will I see it at some trackdays ?
Will there be any "bang bang" ?


https://www.youtube.com/watch?v=QLXtj6EYpJM

WestfarmRacing
07-20-2014, 01:43 AM
Thats nice to hear, have a 550hp a4 with stiffer mounts, and it vibey at idle and low revs.. Thanks jan aimar! Haha it will have some launch, but will be carefull with that =) Its a daily, but maybe try it on track when the chassi is better

WestfarmRacing
07-24-2014, 05:10 AM
They are big, but they seem to fit..
http://img.tapatalk.com/d/14/07/24/jy6ure6y.jpg

WestfarmRacing
08-03-2014, 12:58 AM
Finally its in one piece again. It will run on oem rs4 injectors at first, then later on i will go for bigger ones. Whats taking some time now is tuning in the wg duty cycle and throttle angle with the new turbos. Its fluttering at light-throttle and a little bit of overboost vs. Requested yet. Im sure that's a problem many of you had

http://img.tapatalk.com/d/14/08/03/ahazy4y8.jpg

WestfarmRacing
08-19-2014, 11:12 AM
TFSI coil conversion. The old system didn't like load/boost so got myself a harness from a v6 fsi engine. Have a big pile of coils laying around, so this is really a cheapo mod for me:)

http://tapatalk.imageshack.com/v2/14/08/19/5fb674a7414564ceeb8fe979fe601d1c.jpg

WestfarmRacing
08-25-2014, 01:44 AM
HUGE difference in both mid-range smoothness and Power. Now im able to boost like it should :)

This is a really Nice Upgrade for these cars

JanAimar
08-25-2014, 01:11 PM
HUGE difference in both mid-range smoothness and Power. Now im able to boost like it should :)

This is a really Nice Upgrade for these cars

It really is a nice upgrade. Did the same on mine and it was unrecognisable.

Buuuut... there was a lack of partyswede at the track this weekend ??!!

WestfarmRacing
08-25-2014, 01:56 PM
Haha yes, i know! Had to go to Bergen this weekend.. Try again at Gatebil in a few weeks :) see ya there!

WestfarmRacing
11-15-2014, 09:57 AM
Tweaked my tune a little today, and it runs pretty good for oem rs4 injectors. They are at the limit now, so its time to get some bigger ones.

http://i1135.photobucket.com/albums/m622/WestfarmRacing/airmass_zpsddbad571.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/boost_zps2badfbd5.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/theoregt_zps4d24bc56.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/load-throttle_zps72ea6827.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/retard_zps35b93e56.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/o2_zps8a21a0d0.png

WestfarmRacing
11-20-2014, 02:45 PM
Started upgrading the fueling today. Figured the intank 044 would'nt cut it, so got a surge tank for the engine bay. Thanks again Rosten-performance.

Tomorrow new injectors is going in and it's time for some more tuning.



http://tapatalk.imageshack.com/v2/14/11/20/4a600e5638077c9eedf18ffd006b93d7.jpg
http://tapatalk.imageshack.com/v2/14/11/20/73cfd1a3ba5cdd458e6dec0cd1efb078.jpg

WestfarmRacing
11-23-2014, 08:01 AM
Did some tuning on winter e85 (e70-e75)
I'm restricted to 1,5bar boost for now, but that's ok for the winter.. It stopped making power over 18degrees of ignition up top so I let it be from there
Made 3,12 fats no idea if it's any good, but the car pulls really hard


http://i1135.photobucket.com/albums/m622/WestfarmRacing/e70pwr_zps2b56b7d0.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/massaire70_zps2c911206.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/evmse70_zps04516f3e.png
http://i1135.photobucket.com/albums/m622/WestfarmRacing/e70ign_zpsf623dfd1.png

WestfarmRacing
11-30-2014, 12:11 PM
More power. Now it's ok for the winter I think. Quite satisfied with the result on ~21psi

Yesmar
12-17-2014, 09:03 AM
very nice man

WestfarmRacing
12-22-2014, 07:47 AM
It's winter :)

http://i1135.photobucket.com/albums/m622/WestfarmRacing/10846883_10152863673267527_1399341920_n_zps3257f40 8.jpg

WestfarmRacing
01-10-2015, 03:26 AM
Added 3-bar mapsensor and new remap on e70. The tune still need some fine tuning, but man its moving!

http://i1135.photobucket.com/albums/m622/WestfarmRacing/boost-G_zps6df56b31.jpg

JKnight41
01-11-2015, 01:00 PM
So jealous of this! Awesome build man, congratulations.

WestfarmRacing
01-12-2015, 05:42 AM
So jealous of this! Awesome build man, congratulations.

Thanks, its starting to get fun now. Will update after some more tweaking, but my fuelpump decided do suddently die, and now it's snow here, so it's hard to get good logs for now.

B5 Quattro
01-14-2015, 09:01 PM
Wow !!
Keep it up man. Good read.
��

WestfarmRacing
01-16-2015, 11:20 AM
Wow !!
Keep it up man. Good read.
��

Thanks. We are retuning it now, will post results :)

SleeperAvant
01-20-2015, 05:11 AM
Get some videos!

WestfarmRacing
01-23-2015, 01:32 AM
Get some videos!

Will as soon as roadconditions allow it. It's just spinning as it is now

WestfarmRacing
01-25-2015, 09:42 AM
Video, bad road, so i had to let go on 4th


https://www.youtube.com/watch?v=zNq-na4w9jk&feature=youtu.be

ama
01-26-2015, 12:50 PM
Video, bad road, so i had to let go on 4th


https://www.youtube.com/watch?v=zNq-na4w9jk&feature=youtu.be

yea baby

WestfarmRacing
02-09-2015, 01:00 PM
yea baby

[drive] Will get some better videos as soon as the weather up here is normal again

Meow
02-10-2015, 04:39 AM
Added 3-bar mapsensor and new remap on e70. The tune still need some fine tuning, but man its moving!

http://i1135.photobucket.com/albums/m622/WestfarmRacing/boost-G_zps6df56b31.jpg

I wish we had a better way to compare FATS times with cars that have an rs4 third gear.

It sure is not slow! Awesome car man!


Looks like the tune still has a lot of room to be improved judging by the variations in the acceleration curve so it can only get faster! Love the car and the project man!

WestfarmRacing
02-10-2015, 06:10 AM
I wish we had a better way to compare FATS times with cars that have an rs4 third gear.

It sure is not slow! Awesome car man!


Looks like the tune still has a lot of room to be improved judging by the variations in the acceleration curve so it can only get faster! Love the car and the project man!

Thanks man.

This car has an S4 gearbox FYI :)

The variations differs from pull to pull. I think maybe it is because of soft Winter tyres, but we'll see in the spring. We have really tweaked it for a long time, and couldn't get it faster for now.
Will have to make a New tune for e85 though (this is e70) so time will show.

It feels really fast, and judging by the FATS it must be.

Meow
02-10-2015, 08:04 AM
Thanks man.

This car has an S4 gearbox FYI :)

The variations differs from pull to pull. I think maybe it is because of soft Winter tyres, but we'll see in the spring. We have really tweaked it for a long time, and couldn't get it faster for now.
Will have to make a New tune for e85 though (this is e70) so time will show.

It feels really fast, and judging by the FATS it must be.

Awesome that it is an s4 gear box, makes things nice to compare!

It looks like a very fast car, but what I was talking about for variations in the acceleration curve was the dips. I drew a straight line (obviously not realistic) to give an idea of what I think a smoother acceleration curve should get close to. Why is yours all over the place?

http://i97.photobucket.com/albums/l214/boomerw/Untitled_zps40ffbe64.png

WestfarmRacing
02-10-2015, 08:27 AM
Awesome that it is an s4 gear box, makes things nice to compare!

It looks like a very fast car, but what I was talking about for variations in the acceleration curve was the dips. I drew a straight line (obviously not realistic) to give an idea of what I think a smoother acceleration curve should get close to. Why is yours all over the place?
]

It makes it more realistic that way yes!

I see what you mean, that log was while tuning. After tweaking timing its much smoother.
Here is a log I grabbed from the computer after done tune.

http://i1135.photobucket.com/albums/m622/WestfarmRacing/acc_zpsfwn4pgfd.png

Meow
02-10-2015, 08:29 AM
It makes it more realistic that way yes!

I see what you mean, that log was while tuning. After tweaking timing its much smoother.
Here is a log I grabbed from the computer after done tune.

http://i1135.photobucket.com/albums/m622/WestfarmRacing/acc_zpsfwn4pgfd.png

She is moving out! Great power under the curve. Ethanol for the win!

WestfarmRacing
02-10-2015, 08:42 AM
She is moving out! Great power under the curve. Ethanol for the win!

Ethanol is the mother! It pulls like a train now, with as said a lot of room under the curve.

Not sure what power level it has, but that's not as important as it actually moving

WestfarmRacing
02-21-2015, 12:09 PM
Small driving video. It's still on e70 tune, see if we can squeeze a little bit more out of it in the spring


https://www.youtube.com/watch?v=c7m9OISu6Ug&feature=youtu.be

Mocke
02-23-2015, 11:38 AM
It is wicket mate :) That 3 - 4 gear pull looks like it wants too lift heheh

WestfarmRacing
02-25-2015, 10:13 AM
It feels quite fast now, but the worst part is I feel it could use just a tad more power or an rs4 gearbox hehe

WestfarmRacing
03-18-2015, 04:31 AM
Made this one for Mockes car, really satisfied with it so i need to find some time to make one for my car as well


http://tapatalk.imageshack.com/v2/15/03/18/e59d44bc0303556f728d196d65447319.jpg

WestfarmRacing
06-25-2015, 12:03 AM
Resprayed these cheap-o wheels gold..

http://images.tapatalk-cdn.com/15/06/24/c61961475e8b7db509de675f393dd809.jpg

Jism
10-08-2015, 07:26 PM
It feels quite fast now, but the worst part is I feel it could use just a tad more power or an rs4 gearbox hehe

The RS4 gearbox has some more torque going to the back compared the S4 right and a slightly changed gear ratio?

Check Ebay SWiss or Germany. Sometimes you can find some good used parts for the right price. :)

arotished
10-09-2015, 10:26 PM
The RS4 gearbox has some more torque going to the back compared the S4 right and a slightly changed gear ratio?

Same torque, only different gear ratio in 3rd and 4th gear.

Jism
10-12-2015, 07:34 PM
I think the RS4 has a torq difference from 4:1 to rear and the S4 a 2:1.

I remember i had to figure this all out since my differential was 'done' and i was looking for a spare part. The differentials are the same as the S4/RS4 but the Gearbox is a different kind.

Basicly; torque distribution (RS4 has more to rear) and the 3rd/4rd gear ratio as wel.

jaychen
10-12-2015, 11:13 PM
Basicly; torque distribution (RS4 has more to rear) and the 3rd/4rd gear ratio as wel.

Wrong. It has the same.

Jism
11-14-2015, 09:04 PM
No,


RS4 :

Six-speed manual transmission
(parts code prefix: 01E, identification code: FDP)

Gear ratios:
1st: 3.500, 2nd: 1.889, 3rd: 1.320, 4th: 1.034, 5th: 0.806, 6th: 0.684

S4:

Six-speed C90 manual transmission
(parts code prefix: 01E, identification code: DSY)

Gear ratios:
1st: 3.500, 2nd: 1.889, 3rd: 1.231, 4th: 0.967, 5th: 0.806, 6th: 0.684

About gear differences you are right.


Tuning the center differential provides one of the most significant performance gains available to the Quattro owner. The standard torsen center differential in the S4 and A4 provides a 2:1 torque distribution capability. This enables the end of the car with traction (generally the rear) to deliver twice the torque being delivered by the least tractive end of the vehicle (generally the front). For high performance street cars, we recommend a bias ratio of 4:1. This is the same bias ratio that Audi has provided in the stock RS4 driveline.


Those where the differences between both gearboxes. I had to replace the differential on the back and was wondering if the S4 would be swappable with one of the RS4. The differential can be swapped yes. They are identical.

jaychen
11-16-2015, 04:19 AM
I was not referring to the different gear ratios, I was referring to the B5 S4 and RS4 torque bias. The B5 is the same for both (unless modified aftermarket).

landfill
11-26-2015, 12:42 AM
@jism all the b5's came with 2:1 stock bias center diff's.
The b7 rs4 and b7 25th anniversary s4 have 4:1 torsen centers.
For the b5 chassis you need to modify the center diff with special
big washers or buy an aftermarket 4:1 unit.