Audi B5 420-R: The Build

Nollywood · Post by **Nollywood** » Tue Nov 24, 2015 1:19 am

Update: 22nd November, 2015.

I began the tear down of my Pelican Blue B5 by 14:00 hrs.

As I suspected, the exhaust bolts in the centre section (the sleeves that join the catalysts to the mid mufflers) were too rusty to play nice. 15 years of use, and possibly 15 winters had taken its toll on the exhaust, from the front flexi pipes to the rear muffler. Although not holed, the whole assembly was in pretty bad shape.

As I am not running this exhaust with the V8, I simply undid the retainers, then ran a cutting disc through the damn thing. I was in a bit of a rush, as the engine was due to be picked up today, so I pulled the motor solo. I was later called by the buyer to ask if it was okay to pick the engine up next week. I agreed, after all, it's been paid for.

The 01A is all unbolted, propshaft has been removed, driveshafts disconnected, but left in situ. I just need to unbolt the clutch master cylinder, I won't be using it though, as I prefer to fit the aluminium version, which I have. The plastic ones have a habit of exploding under extreme pressure and load.

Pictures!

Nollywood · Post by **Nollywood** » Tue Nov 24, 2015 1:22 am

I've been making final preparation before B5 420-R gets her new heart and driveline.

With all my previous B2 and B5 V8 swaps, no 2 have ever been the same, and this is no exception. However, this is one that I have not rushed into, that I want to turn out OEM+.

Now, the aircon compressor of the D3 V8, like most late model cars is a variable displacement unit, meaning no magnetic clutch, the swash plate angle varies in angle from quite shallow to pretty steep, effectively varying the swept volume. The B5 V6 compressor on the other hand employs a magnetic clutch, giving a simple on / off status, and a fixed swept volume.

Whilst the D3 compressor can be made to work in the B5, it will be much less time consuming to use the B5's unit. I have removed it, and given it a thorough chemical clean, taking care to keep the ports plugged with rubber grommets. Over the weekend, I will paint it in the standard colours of aluminium silver and satin black, before removing the D3 V8's compressor, and swapping in the B5 item.

Wiring wise, the chassis plugs are the same, there were 6 wires that I needed to move around, so they match those on my original APR harness.

There are some B5-specific wires that are missing from the corresponding positions in the D3 chassis plugs:

Oil temperature feed (1 wire).
Back-up light feed (2 wires).

These I will add to the D3 plugs - the pins and actual wires. The D3 does not have an oil temperature sender, but again, I'm going to fit a Y-splitter in the oil pressure switch location, which will accept both the oil pressure and temperature senders.

ChrisJC · Post by **ChrisJC** » Tue Nov 24, 2015 8:49 am

What a packaging nightmare! You don't want to drop a tool in the engine compartment!, you'd never see it again!

Chris.

Nollywood · Post by **Nollywood** » Sun Nov 29, 2015 10:26 pm

Update: 29th November, 2015.

I finally mated my 40V BFM motor to my 01E 6-speed.

I would have thrown both into the engine bay, but I need to replace the power steering high pressure line (PAS rack to vane pump) first. It can be done with the engine and transmission bolted into the car, it just involves more effort, cursing and losing some skin.

I also need to obtain an adapter to mate my facelift clutch slave cylinder line to my steel RS4 slave. As I had previously fitted this transmission and slave cylinder to my 1996 A4 B5 V8, I've long tossed the adapter. One of the reasons every bit of car always comes in useful, and should never be junked, unless you've got loads of them.

Nollywood · Post by **Nollywood** » Thu Dec 03, 2015 8:37 pm

One thing that seems to be common to radiators with B5 V8 swaps, both stock B5 / C5 and aftermarket aluminium is the fairly small inlet and outlet pipes.

They are generally 28-30mm ID. My original D3 radiator pipes were 34.6mm. So we're talking at least 6.5mm difference. Both my B5 30V and my B5 aluminium radiator pipes also have a 28mm ID.

Now this may not seem a big deal, but consider this - going from the D3 V8's 34mm to 28mm will NOT help cooling. The resultant bottleneck will increase pressure slightly, and move the coolant round slower. The larger pipe bores, that match the V8's OEM coolant hoses will drop pressure, but increase flow which is beneficial, as it keeps the coolant in the cylinder block and radiator for slightly shorter periods, allowing more heat to be dissipated, which also eliminates localised hot spots.

My B5 aluminium radiator has both the inlet / outlet on the same side, the left, while the V8 has the hoses on the right. I originally purchased a pair of aluminium pipes, to have welded on the right hand side of the radiator. But...they are 28 and 32mm ID and OD respectively. I ordered a replacement pair, which were delivered today - 34mm ID to match the V8 radiator inlet and outlet hoses. I'm taking the aluminium radiator and the new pipes to my Bodyshop to have the pipes welded into the correct location, and the originals on the left cut off, with aluminium discs welded in place.

I'll post pictures once it's all done.

stevieturbo · Post by **stevieturbo** » Thu Dec 03, 2015 9:50 pm

More flow is always good, slow flow is bad !

Nollywood · Post by **Nollywood** » Thu Dec 03, 2015 11:09 pm

stevieturbo wrote:More flow is always good, slow flow is bad !

Very true. My explanation was clumsy. I've just finished a 14-hour shift, dead tired. I'll edit my post when I'm more awake.

Nollywood · Post by **Nollywood** » Sat Dec 12, 2015 10:56 pm

Update: 12th December, 2015.

I received my replacement flywheel, which meshes perfectly with my starter motor. Happy with that. The B5 RS4 clutch and 01E have been reunited with the BFM 40V.

So today, I...

Installed B5 S4 front axles. In my previous B5 V8, I had no access to S4 axles, so I ended up swapping B5 A4 Quattro rear differential output flanges (100mm) so I could run the stock B5 2.6 12V Quattro axles.

Luckily I didn't junk the original S4 01E 108mm flanges, which I've refitted to my 01E.

My 01A had been sitting on the subframe, so I yanked it out. I fitted new OEM V6 gearbox mounts, and the C5 S6 motor mount lower brackets. Tomorrow, I'll pick up a positive cable, to fit between the BFM water-cooled alternator and starter motor. The B5 2.8 30V lead is too short.

It's a rare opportunity to get full access to the engine bay, with the motor in place, so I seized the moment. I removed all the heat shields, and gave the hidden areas a good clean, it's looking pretty good, it'll look even better with the BFM motor filling the yawning gap tomorrow.

Some pictures:

stevieturbo · Post by **stevieturbo** » Sat Dec 12, 2015 11:29 pm

It always amazes me how they managed to bolt an engine in longways, with a transaxle and still be able to have shafts reach the front wheels

Nollywood · Post by **Nollywood** » Wed Dec 16, 2015 7:01 pm

Back in 2008/9 when I first began B5 V8 swaps, I used 077 series V8 motors, both in 32 and 40V guise. These engines came from D2 and C5 chassis, and with a little work, I got them virtually plug-and-play in the B5 chassis, and created a resource thread on OZ Audi, for anyone who may wish to tread the same path.

This time, my V8 swap is different. Whilst I could swap a C5 / D2 V8 into a B5 in a weekend, I have opted to use a V8 40V from a 2005 D3 A8. As I have stated previously, the BFM block IS the same as used in the C5 RS6 (BCY). So my write up on OZ Audi is not much use with this configuration.

The engine is now mounted in my Pelican Blue B5. No easy task, suffice to say I will do another "how to" once it's all done, so anyone wanting to go down the same route can refer to my resource write-up.

Some pictures from the 13th December 2015:

ChrisJC · Post by **ChrisJC** » Fri Dec 18, 2015 6:41 pm

stevieturbo wrote:It always amazes me how they managed to bolt an engine in longways, with a transaxle and still be able to have shafts reach the front wheels

That's Audi for you - silk purse, sows ear. Nobody in their right mind makes a front wheel drive V8. The number of technical compromises in that car is endless.
BMW on the other hand.....

Chris.

P.S. Nobody in their right mind makes a front wheel drive car with a longitudinal engine full stop.

stevieturbo · Post by **stevieturbo** » Fri Dec 18, 2015 7:02 pm

ChrisJC wrote:
stevieturbo wrote:It always amazes me how they managed to bolt an engine in longways, with a transaxle and still be able to have shafts reach the front wheels
That's Audi for you - silk purse, sows ear. Nobody in their right mind makes a front wheel drive V8. The number of technical compromises in that car is endless.
BMW on the other hand.....

Chris.

P.S. Nobody in their right mind makes a front wheel drive car with a longitudinal engine full stop.

I'd far sooner own the Audi than the BMW though in most cases.

Nollywood · Post by **Nollywood** » Fri Dec 18, 2015 7:32 pm

ChrisJC wrote:
stevieturbo wrote:It always amazes me how they managed to bolt an engine in longways, with a transaxle and still be able to have shafts reach the front wheels
That's Audi for you - silk purse, sows ear. Nobody in their right mind makes a front wheel drive V8. The number of technical compromises in that car is endless.
BMW on the other hand.....

Chris.

P.S. Nobody in their right mind makes a front wheel drive car with a longitudinal engine full stop.

You've kind of lost me.

Audi don't make a FWD V8.

mgbv8 · Post by **mgbv8** » Fri Dec 18, 2015 7:54 pm

This last page was great!!

I scrolled down from top to bottom and it was like a flicker book

Some serious work going on there Nolly

Perry

stevieturbo · Post by **stevieturbo** » Fri Dec 18, 2015 10:45 pm

Nollywood wrote:
ChrisJC wrote:
stevieturbo wrote:It always amazes me how they managed to bolt an engine in longways, with a transaxle and still be able to have shafts reach the front wheels
That's Audi for you - silk purse, sows ear. Nobody in their right mind makes a front wheel drive V8. The number of technical compromises in that car is endless.
BMW on the other hand.....

Chris.

P.S. Nobody in their right mind makes a front wheel drive car with a longitudinal engine full stop.
You've kind of lost me.

Audi don't make a FWD V8.

No, but the nose heavy transaxle arrangement certainly isnt the best design, but it certainly works.