Okay here it goes... Hello S2forum!
I wanted to make this post as detailed as possible to compile all my research, questions and findings into one place. This would make it easy for myself and other people who want to do this conversion to their small chassis Audi 80/90/Coupe B3/B4.
While looking for information on my specific project, a 95' Audi B4 80 Quattro Avant, Originally an ABC V6. I was only able to find limited bits of information from various sources, sometimes really helpful, incorrect or otherwise.
The donor cars for my project are a 93' Audi C4 S4 AAN, slush box auto and a 99' B5 S4 AGB, manual 01E DSY. I plan to mate the AAN with the 01E DSY.
So let's get started!
Please feel free to chip in, correct me and offer advice as to what will or won't work, anything I have missed and maybe some tips along the way to make life easier! It would be muchly appreciated.
I will highlight my questions in RED so hopefully they can be easily seen and answered.
For simplicity's sake from here on in I shall refer to the C4 S4/S6 CBL 01E as just "C4 01E" and the B5 S4 DSY 01E as just "B5 01E".
- Engine Mounting, putting the AAN into the B4 80 chassis will require 5 cylinder things. 5 cylinder mount brackets need to be welded onto the chassis legs/ frame rails.
Part numbers:
Chassis/ frame rail brackets, 8A0803029B & 8A0803030C (80/90 B3)
Engine block brackets, 893199307A & 893199308B (RS2/ ABY)
Engine mount rubbers, 8A0199382D & 8A0199382 (RS2) (unconfirmed fitment but will update)
Picture of factory V6 engine mounts.
Audi 80 059.jpg
Picture off the V6/ inline 4 cylinder mounts removed.
Audi 80 068.jpg Picture of inline 5 cylinder mounts offered up to the general location of welding. Original bolt holes need to be removed first.
Audi 80 065.jpg Audi 80 066.jpg A picture of the final product. Sorry not my pic, all credit to TurboS for this one!
mount 1.png
- Engine & Gearbox Mating, This is specifically for joining together the AAN and B5 01E together as we know the C4 01E is factory fitted to the AAN.
When mounting the B5 01E there isn't all that much to over come. I only had to modify one bolt hole and no cutting or clearancing is required for the rpm & crank position sensors to fit!
I will go over this in detail now as all of the research previous to my own experience said otherwise.
Here is a bolt pattern diagram I made which includes exact bolt sizes and lengths that you will require to mount the B5 01E onto the AAN, If you are sourcing these bolts from my diagram make sure you get as close to the length as stated otherwise some of the bolts will bottom out in a few of the blind holes.
Here are the diagrams
Audi 80 0228.jpg
p5pb22361869.jpg The bolts I have used here are a mixture of factory C4 S4 AAN automatic gearbox bolts and B5 01E bolts.
image_84706.jpg Bolts 6,7 & 8 can been seen from the back side with yellow paint pen on the thread where they need to be cut as measured from the diagram list, this isn't necessary to fit but will be a tidy install, they are way longer than the need to be!
You won't have any problems with one of the dowel sleeves not fitting unless you are planning you to use the 01E gearbox spacer for purposes of fitting a factory dual mass flywheel and clutch arrangement. I don't have a clutch that fits yet so I'm going to have to buy something new (probably a southbend or similar) therefore I wont be using the spacer.
Here is the dowel in question if you want to use the spacer you will have to drill out the spacer to fit.
Audi 80 0219.jpg This is the outer diameter of the dowel.
Audi 80 0220.jpg This is the inner diameter of the spacer.
Audi 80 0221.jpg
This is the hole you will need to modify by drilling it out to a larger size to accept the bolt. It's in the sump only as the gearbox receiving hole is already the correct size. So that's a huge bonus!
Audi 80 0222.jpg The hole is only 9.38mm in diameter but the bolt is 9.87.
Audi 80 0223.jpg Audi 80 0224.jpg As you can see here it threads into the gearbox nicely.
Audi 80 0225.jpg Okay lets make this puppy bigger! I drilled out the hole carefully from the backside with a 10.5mm drill bit then de-burred both sides of the sump with a countersunk bit, ever so slightly! Hope you have a steady hand for this one
Audi 80 0226.jpg The bolt in it's new home.
Audi 80 0227.jpg
Okay back to talking about that dowel hole again... This time it's the gearbox side, the hole in the gearbox is a much larger inner diameter than the bolt going through it! I knew about this from researching and thought maybe a sleeve could be inserted to compensate for this.
On closer inspection, it looks like the bolt is a little offset in the hole. At this point I figured that a sleeve would be more complicated than its worth. The head of the bolt is wide enough to get a good grip on the gearbox and I have no doubt that this won't be a problem so I'm just going to leave this one as is.
p5pb22362095.jpg Audi 80 0232.jpg 17.15mm is the inner diameter of the hole in the gearbox, the bolt being an M12.
Audi 80 0233.jpg
- Gearbox Mounting, C4 01E into the B4 80 chassis can be achieved using the original ABC V6 subframe and a pair of transmission/ gearbox mounts from an RS2. Part numbers: 8A0399113E & 8A0399114E.(See below posts for more detail).
The gearbox mount brackets for the C4 & B5 01E's are not the same part numbers but the bolt holes are identical and they are interchangeable between gearboxes.
If you were to use a 5 cylinder subframe, then the right hand side gearbox mount would sit approx 28mm too high using C4 01E gearbox mounts and would require a spacer to be made.
B5 01E mounts are well off.
- Shifter Box Mounting, I will be test fitting the B5 01E shifter box into the B4 80 chassis, the bolt holes are identical but you need to remove the captive nuts and a stud that holds a trim bracket from the inside of the 80 B4 tunnel. Then it can be bolted straight in, I need to test shifter rod and support rod clearances however.
If you wish you can just retain the original B4 80 components then mod the B5 01E shifter rod to fit.
- Gear Shifter Modification, Using the B5 01E shifter rod it can be modified to work. Cut the end off one end, rotate cut end 180 degrees and weld back on. There are some good write ups around the internet on this already!
Have a read of this well put together example https://www.motorgeek.com/threads/01...nto-b3.215233/
- Clutch Arrangement, 7A SMFW (single mass flywheel) can be used with related 7A clutch disk and pressure plate.B5 01E dual mass flywheel and clutch can't be used. (See below posts for more detail).
- Clutch Slave Cylinder, Retaining the B5 01E clutch salve, needs to have the input line modified. (See below posts for more detail).
- Rear Differential & Locker, The entire B5 S4 rear subframe is almost identical to the B4 80q. The B5 S4 rear hubs are about 8mm wider, the toe arms are about 15mm longer, the handbrake cables are shorter, rear brake calipers and discs are bigger and the brake lines are two lines from abs pump to rear brake calipers.
I have swapped over the rear carrier with abs sensors, hubs, brakes, diff and axles from the B5 S4 into the B4 80q subframe, retaining the B4 80q handbrake cables and handbrake actuators which bolt to the rear calipers A 4.11 Type 44 R&P (ring wheel and pinion gear) might swap into a B4 diff and allow you to keep the B4 80q locker?
- Wiring, I don't really have any questions about the wiring at this stage. Feel free to chuck in some good links if you have them though!
Let me know what you think, thanks for reading and appreciate any help!
P.S. I will be editing this first post and the other posts below when I confirm findings to keep this information as up to date as possible for anyone who wants to know.
I wanted to make this post as detailed as possible to compile all my research, questions and findings into one place. This would make it easy for myself and other people who want to do this conversion to their small chassis Audi 80/90/Coupe B3/B4.
While looking for information on my specific project, a 95' Audi B4 80 Quattro Avant, Originally an ABC V6. I was only able to find limited bits of information from various sources, sometimes really helpful, incorrect or otherwise.
The donor cars for my project are a 93' Audi C4 S4 AAN, slush box auto and a 99' B5 S4 AGB, manual 01E DSY. I plan to mate the AAN with the 01E DSY.
So let's get started!
Please feel free to chip in, correct me and offer advice as to what will or won't work, anything I have missed and maybe some tips along the way to make life easier! It would be muchly appreciated.
I will highlight my questions in RED so hopefully they can be easily seen and answered.
For simplicity's sake from here on in I shall refer to the C4 S4/S6 CBL 01E as just "C4 01E" and the B5 S4 DSY 01E as just "B5 01E".
- Engine Mounting, putting the AAN into the B4 80 chassis will require 5 cylinder things. 5 cylinder mount brackets need to be welded onto the chassis legs/ frame rails.
Part numbers:
Chassis/ frame rail brackets, 8A0803029B & 8A0803030C (80/90 B3)
Engine block brackets, 893199307A & 893199308B (RS2/ ABY)
Engine mount rubbers, 8A0199382D & 8A0199382 (RS2) (unconfirmed fitment but will update)
Picture of factory V6 engine mounts.
Audi 80 059.jpg
Picture off the V6/ inline 4 cylinder mounts removed.
Audi 80 068.jpg Picture of inline 5 cylinder mounts offered up to the general location of welding. Original bolt holes need to be removed first.
Audi 80 065.jpg Audi 80 066.jpg A picture of the final product. Sorry not my pic, all credit to TurboS for this one!
mount 1.png
- Engine & Gearbox Mating, This is specifically for joining together the AAN and B5 01E together as we know the C4 01E is factory fitted to the AAN.
When mounting the B5 01E there isn't all that much to over come. I only had to modify one bolt hole and no cutting or clearancing is required for the rpm & crank position sensors to fit!
I will go over this in detail now as all of the research previous to my own experience said otherwise.
Here is a bolt pattern diagram I made which includes exact bolt sizes and lengths that you will require to mount the B5 01E onto the AAN, If you are sourcing these bolts from my diagram make sure you get as close to the length as stated otherwise some of the bolts will bottom out in a few of the blind holes.
Here are the diagrams
Audi 80 0228.jpg
p5pb22361869.jpg The bolts I have used here are a mixture of factory C4 S4 AAN automatic gearbox bolts and B5 01E bolts.
image_84706.jpg Bolts 6,7 & 8 can been seen from the back side with yellow paint pen on the thread where they need to be cut as measured from the diagram list, this isn't necessary to fit but will be a tidy install, they are way longer than the need to be!
You won't have any problems with one of the dowel sleeves not fitting unless you are planning you to use the 01E gearbox spacer for purposes of fitting a factory dual mass flywheel and clutch arrangement. I don't have a clutch that fits yet so I'm going to have to buy something new (probably a southbend or similar) therefore I wont be using the spacer.
Here is the dowel in question if you want to use the spacer you will have to drill out the spacer to fit.
Audi 80 0219.jpg This is the outer diameter of the dowel.
Audi 80 0220.jpg This is the inner diameter of the spacer.
Audi 80 0221.jpg
This is the hole you will need to modify by drilling it out to a larger size to accept the bolt. It's in the sump only as the gearbox receiving hole is already the correct size. So that's a huge bonus!
Audi 80 0222.jpg The hole is only 9.38mm in diameter but the bolt is 9.87.
Audi 80 0223.jpg Audi 80 0224.jpg As you can see here it threads into the gearbox nicely.
Audi 80 0225.jpg Okay lets make this puppy bigger! I drilled out the hole carefully from the backside with a 10.5mm drill bit then de-burred both sides of the sump with a countersunk bit, ever so slightly! Hope you have a steady hand for this one
Audi 80 0226.jpg The bolt in it's new home.
Audi 80 0227.jpg
Okay back to talking about that dowel hole again... This time it's the gearbox side, the hole in the gearbox is a much larger inner diameter than the bolt going through it! I knew about this from researching and thought maybe a sleeve could be inserted to compensate for this.
On closer inspection, it looks like the bolt is a little offset in the hole. At this point I figured that a sleeve would be more complicated than its worth. The head of the bolt is wide enough to get a good grip on the gearbox and I have no doubt that this won't be a problem so I'm just going to leave this one as is.
p5pb22362095.jpg Audi 80 0232.jpg 17.15mm is the inner diameter of the hole in the gearbox, the bolt being an M12.
Audi 80 0233.jpg
- Gearbox Mounting, C4 01E into the B4 80 chassis can be achieved using the original ABC V6 subframe and a pair of transmission/ gearbox mounts from an RS2. Part numbers: 8A0399113E & 8A0399114E.(See below posts for more detail).
The gearbox mount brackets for the C4 & B5 01E's are not the same part numbers but the bolt holes are identical and they are interchangeable between gearboxes.
If you were to use a 5 cylinder subframe, then the right hand side gearbox mount would sit approx 28mm too high using C4 01E gearbox mounts and would require a spacer to be made.
B5 01E mounts are well off.
- Shifter Box Mounting, I will be test fitting the B5 01E shifter box into the B4 80 chassis, the bolt holes are identical but you need to remove the captive nuts and a stud that holds a trim bracket from the inside of the 80 B4 tunnel. Then it can be bolted straight in, I need to test shifter rod and support rod clearances however.
If you wish you can just retain the original B4 80 components then mod the B5 01E shifter rod to fit.
- Gear Shifter Modification, Using the B5 01E shifter rod it can be modified to work. Cut the end off one end, rotate cut end 180 degrees and weld back on. There are some good write ups around the internet on this already!
Have a read of this well put together example https://www.motorgeek.com/threads/01...nto-b3.215233/
- Clutch Arrangement, 7A SMFW (single mass flywheel) can be used with related 7A clutch disk and pressure plate.B5 01E dual mass flywheel and clutch can't be used. (See below posts for more detail).
- Clutch Slave Cylinder, Retaining the B5 01E clutch salve, needs to have the input line modified. (See below posts for more detail).
- Rear Differential & Locker, The entire B5 S4 rear subframe is almost identical to the B4 80q. The B5 S4 rear hubs are about 8mm wider, the toe arms are about 15mm longer, the handbrake cables are shorter, rear brake calipers and discs are bigger and the brake lines are two lines from abs pump to rear brake calipers.
I have swapped over the rear carrier with abs sensors, hubs, brakes, diff and axles from the B5 S4 into the B4 80q subframe, retaining the B4 80q handbrake cables and handbrake actuators which bolt to the rear calipers A 4.11 Type 44 R&P (ring wheel and pinion gear) might swap into a B4 diff and allow you to keep the B4 80q locker?
- Wiring, I don't really have any questions about the wiring at this stage. Feel free to chuck in some good links if you have them though!
Let me know what you think, thanks for reading and appreciate any help!
P.S. I will be editing this first post and the other posts below when I confirm findings to keep this information as up to date as possible for anyone who wants to know.
Comment