0A3-transmission

[7Aquattro]

Hello,

I am thinking of putting a 07K into my Typ 85 and maybe a 0A3-transmission. As far as I know, it originally came in the B6/7 S4/RS4 and some C6 quattros.

Has anyone tried this?

Thank you all in advance!

[Error404]

Yes, its a great swap. I much prefer the 0A3 to the old 01E - much more refined. Its unlikely to be as strong as the 01E but I've not heard of any spectacular failures, mostly the syncros seem to be the weak point. The RS4 version is 4.11 final drive, the S4 is 3.89. Obviously you need a rear diff to suit either option. B7 are the ones to go for because of the T3 centre diff with 40:60 static split and a higher torque bias ratio
You can find all the info in my project thread if you search the forum.
Just FYI I am about to start producing a conversion kit

[7Aquattro]

Thank you!

I found your thread, but can't see any of the pictures.

Are you using the central mounting point in the back?

And the C6 multitronic axles are working well?

Cool project in any case!

[Error404]

****ing Photobucket c nuts have disabled my links.
I fabricated mountings to mount to the stock subframe
Yes CVT shafts work perfectly

[rxl]

whats the difference HLD,JMH ??

[7Aquattro]

Hm, don't know.

I thought JMH was the code for the RS4 transmission. But many ads on ebay etc. use HLD. Maybe it depends on what year the transmission is from.

[diesel des]

I can agree with Alex and say the 03a is a nice box. I have one in my urq which Alex gave plenty of advice about shafts and Speedos etc.

Sent from my Moto G (5) using Tapatalk

[rxl]

i hope it does feel better than the old rs2 gearbox. just bought myself a rs4 gearbox

[Error404]

I believe the HLD was the earlier box - this is what I have. I understand the later box had a revised 1st-2nd shift hub and 2nd gear but not 100% sure on that info
For sure the syncros are the weak point in these transmissions so be gentle

[7Aquattro]

Hi,

another question for the people in the know:

Are the transmissiom tunnels of S2 and Type 85 the same? Alex, you wrote in your thread, that the 0A3 was touching prior to swapping in the Porsche bearings. Is the 0A3 bigger than the 01A/01E/016?

EDIT:

I just saw that diesel das has one in his quattro, so it should fit an 80 quattro as well.

Thanks,

Gilbert

[Error404]

The tunnel is different on Type 85 and Type 89, S2 tunnels are different too. OA3 is wider than O1E but Des has fitted to his URQ with no problems. I had some problems with the gearbox bumping the chassis occasionally but my gearbox mounts were 20 years old and had a lot of movement. No problem with new OEM or stiffer mounts like the Porsche items

[jaybquick@JHM]

Hey guys hopefully this helps with the swap. Back in 2008 the S2 community reached out to us for a linkage back. We built it and now it is distributed through 034 motorsport since we are a B5 and newer company primarily. I was doing some searches and checking on our site's SEO and ran into this thread. I know your linkage and mounting for the 01e is different than the B5 S4 but we did this swap in a C5 4.2l allroad originally back in 2015 and made the appropriate electronics and mounts to make it work.

Here is the more popular B5 S4 2.7t recipe we made for this swap. I know the S2 guys use much of the S4 transmissions etc so hopefully some of this helps you guys figure making this swap more doable.

https://jhmotorsports.com/jhm-b5-s4-...arts-list.html


A couple pointers since we have done this swap on many cars now from a 4.2l C5 allroad to a 4.2l C5 S6 to a 2.7t B5 S4 and we have rebuilt hundreds of these transmissions.
1. The 3 piece synchros 0A3 are FAR superior to the 01E even if it has our JHM Performance Carbon synchros. Basically 3 times the surface area so inherently the 0A3 can shift above 8000 rpm all day long wtihout skipping a beat (also we do now make 0A3 Performance Carbon Synchros)
2. RS4 transmissions (code JMH or HLD) has a 4.11 final drive like the 01e so no rear diff swap is needed but the gear ratios are MUCH lower than the B6-B7 S4 transmission due to the RS4 engines low torque and 8000+rpm factory rev limit. So depending on your setup you may find the ratios too short especially if you have something that doesn't rev to 8000 rpm. The RS4 transmission has the more moder T3 diff which is already 4:1.
3. B6-B7 S4 transmissions (code HEP, FVD, HSM with T2 2:1 center diff for B6 and some 05.5 B7) and (code HVM, JMF with 4:1 T3 center diff) all have a 3.89 final drive so you would need to find a 3.89 rear diff for your chassis car, off the top of my head I am unaware of any options you may have, I am sure some S2 gurus on here would know.
4. 0A3 transmission cores that are in good used shape or rebuildable are MUCH MUCH more common than the 01E nowadays. Over here in the US we rarely see a good B5 S4 2.7t (edu trans code) core anymore that doesn't need at least 2 to 3 gears which cost about $500 each.
5. The 0A3 gears, collars and mainshafts are 1/2 to 1/3 the cost than 01E hard parts from Audi so this is a plus as well.
6. We have gone 10.7 @ 130mph in a full weight RS4 multiple times and 10.9 with some other RS4s, so we have seen similar strength to the 01E transmission but with more available parts and much better high rpm shifting. We have also gone 11.0 @ 130mph with our B6 S4 and zero transmission problems as well.


Hopefully this helps and don't plan on me popping in back here since I rarely get online these days from my duties running my company and heading up R and D. So I dumped what I knew to hopefully help you guys get a nice swap list together. I love this kind of stuff. Take care.

Jason

[Error404]

already available

https://www.s2forum.com/forum/member...conversion-kit

[S2_Rennfahr]

01E modified CV flanges to fit 0A3 gearbox.

[_ShurikeN]

Nice. And interesting linkage.

What about white sensor? Is is for vehicle speed?