Project 4.2 A4 has officially begun.

[tinytim]

Make sure those flaps inside the intake manifold aren't stuck. Mine were seized for sure.

First thing I checked. Unfortunately one of the vacuum secondary linkages is broken... other then that its pretty solid.

I actually just got my 4.2 swap running and driving. The DBW conversion wasn't really too bad. Fortunately, I had bought the whole A6 for a parts car, which made it much easier to do. I kept my cruise control, which meant running the harness to the steering column as well. You'll also need to add a clutch switch for the ECU. It's pin 39 on the ECU and goes to pin 13 on the white harness plug.

Are you running a dual mass flywheel or single mass? I ran the dual mass on mine for how smooth it makes everything, but I had to add a small shim between the crank and flywheel or the flywheel will touch the rear main seal cover.

Keep up the good work!

Thanks! Right now I'm using a stock 30v v6 flywheel. Thanks for pointing out the clutch wiring pin!

[bhusted]

Thanks! Right now I'm using a stock 30v v6 flywheel. Thanks for pointing out the clutch wiring pin!

Yeah. I'm using the stock 30V flywheel as well. Check the clearance between the back of the flywheel and the rear main seal. Mine rubbed when I bolted the flywheel tight.

[Nollywood]

Why would you go with a 2001 v8 vs a 2004 or newer v8? It's a much shorter block. Shoehorning a V8 in a b6 was a task. Loved my b6 s4 until it came to filling it up. Welcome to the world of 12 mpg

The same reason I wouldn't buy a B6 S4. The rear chain-driven set-up is not the most reliable. Replacing the chains requires an engine pull, same goes if replacing just the tensioners. There are 4 seperate chains at the rear, if you've ever had to work on one of these engines, you'd leave it well alone.

Unless you automatically assume "newer" means "better?"

[tinytim]

Got the heads back on today.



Unfortunately I discovered a broken cam timing chain tensioner pad... easy fix at least... the one from my old 2.7t will fit.

Tough to see whats going here but shes broken into a few pieces.

[bhusted]

Looks familiar...


I too had a broken tensioner pad. Once I found one broken one, I elected to replace all 4. If one failed, the others can't be far behind. Another preventative maintenance item is the coolant pipe to the oil cooler. The stock one is plastic and prone to cracking. While I had the engine out, I replaced mine with an aluminum one from Ebay.

http://www.ebay.com/itm/261199474198...S:3160&vxp=mtr

The oil cooler is actually a part of the passenger side engine mount and may require pulling the engine to replace when installed on a B5.

[onemoremile]

Good stuff!

[Iapetos]

Very nice

[tinytim]

Thanks guys. Needed to take a little break from this project for a much needed vacation. Picking up engine brackets, DBW harness, and sub frame this week. I want this thing running ASAP!!!!

[bhusted]

Picking up engine brackets, DBW harness, and sub frame this week. I want this thing running ASAP!!!!

In the DBW harness, be sure to get the brake switch, clutch switch and cruise control wires. They will be different from your DBC car. All of this is part of the white body plug from the engine harness.

[tinytim]

TOUCHDOWN! A6 4.2 mounts came in today and she fits like a glove.



Its so close I can almost taste it. Only thing holding me up right now is the subframe. Hopefully I can pick it up this weekend or early next week.

[walky_talky20]

Every time I see photos of another 40V in a B5, I feel worse about myself for not doing this yet.

Thanks.

[tinytim]

Every time I see photos of another 40V in a B5, I feel worse about myself for not doing this yet.

Thanks.

No problem... and to think... less then a year ago I never owned a VAG vehicle. 1 year in, fully hooked, 2nd swap... more to come I am sure. So far this swap has been pretty simple... I don't know why more people don't do it. A lot of people do love turbo/bi-turbo cars... can't blame them there. I love my 2.7t but I have always wanted a fast N/A car, so I am making it happen. Kinda like a modern day German muscle car!

[s2the4]

Man I wonder who keeps getting you all those parts overnight from Japan :) Intake Manifold, engine mounts. I bet you whoever you are getting them from could deliver a subframe to you...

[wolfe2118]

Here you go, this is the set up I used to make my downpipes for my 32V build. I also have the entire DBW setup if you still need one. Pedal, harness, brackets, etc.

http://www.summitracing.com/parts/sum-g4756
http://www.summitracing.com/parts/sum-670175
http://www.summitracing.com/parts/vpe-62804

Anyone know where I can find exhaust flanges that will bolt to the exhaust manifolds... or just even the correct bolt pattern size? Thanks duuuudes

Like this (but with the correct flange obviously):



Like this would be ideal:

[tinytim]

http://www.summitracing.com/parts/sum-g4756

That's it and only $20, thanks for the link. I swear I looked on summit but I must have missed it!

PM sent on the parts!

[tinytim]

Back at it! Had some free time so I got some more done today.

Got the cam chain guide replaced, installed timing belt, water pump, and idlers. Resealed the oil pan, replaced valve cover gaskets, exhaust gaskets, and intake gaskets. Got the clutch swapped over and then installed trans. Everything fit together perfectly thanks to your guys help! Did another test fit of the engine and trans, everything seems to be in the correct spots.



Test fit with trans:



TT motor and the 4.2 hanging out....


Goooooooooolllllldddddddddddd


DBW stuff came in the other day. Still need to pick up the subframe and exhaust parts. Going to start working on the harness soon (not looking forward to that).

[bhusted]

Looking good!

[tinytim]

Anyone got a pdf format wiring diagram for the 4.2 engine? Been looking around without much luck. Got a full b5 a4 wiring diagram but cant find the c5 a6 4.2 diagrams. Any links or files would be greatly appreciated!!!

[bhusted]

I've got the diagrams for the ART. PM me your email address and I can send them.

[94jedi]

Amazing how far these swaps have come. When I was a B5 regular (over 6 or 7 years ago), If you even hinted at a 4.2 swap, you were instantly "flamed". lol. Hell, even a 2.7TT swap into an A4 would earn you in troll status. Now the B5 platform has had all sorts of VAG goodies stuffed between its fenders.

[tinytim]

Purists will always hate on anything other then factory, I don't see what the fun in that is. Just let people do whatever they want. I stayed away from forums for awhile because people did nothing but hate on each other... seems like they have gotten a lot better. Just about everyone on here has something good to contribute, which is pretty awesome, it has made this project go quite smooth. This is the second VAG vehicle I have ever worked on, the amount of information you guys have helped provide me with is incredible. Thanks guys!

[JumboBlack1.8]

What's your email address? I have the AWN/BBD diagrams saved somewhere in my email address. They are scanned pictures from my Bentley manual (I had to send them to another member at one point).

PM me, and I'll dig around.

[tinytim]

Thanks. 2 members have sent me diagrams. I appreciate it though. Should have some free time this week to get the wiring done. I am itching to hear this thing run!

[tinytim]

This is how I'm spending my morning... and yesterday evening... and yesterday afternoon.



Kinda getting things figured out... kinda frustrated at this point... electric spaghetti

[tinytim]

Lots of wiring progress... not quite there yet.

[KraemerSXED]

I remember the wiring, the best part of the process....lol.

Now I know some other people are thinking the same thing as me. But why did you go with an A6 4.2l? I am glad to see all these swaps myself but I am surprised that the majority is with the A6 4.2l. In my eyes, if your going to go through with this swap, get the S6 or S8 4.2l. But good luck, seems like your moving along at a nice pace. I need to work on mine this weekend.

[revolution337]

A6 motors are cheaper and easier to come by than their S counterpart.

[tinytim]

^ Exactly. This whole project including buying the car is practically the same cost as an s engine. I feel that with built heads and a good tune I could get close to 340hp... MAYBE 350hp. I plan to buy spare heads, do a port match intake/exhaust and port and polish the heads. Planing for bigger valves and a cam re-grind if that's a viable option. Other option is an rs6/8 turbo set up... that's dreaming though! Finding those manifolds in the US is just about impossible.

Anyone seen a ITB set-up on the 4.2? That would sound ridiculous I bet!

[revolution337]

I've seen ITBs on a newer RS4 motor.

[silverman]

Please do an ITB set up. That would be wonderful.

[bhusted]

The additional torque from this V8 will be more than enough to hold you over when you get it running. It's hard to drive mine "nicely" because it's so much fun.

[A4Rob]

Every time I see photos of another 40V in a B5, I feel worse about myself for not doing this yet.

Thanks.

Exactly how I feel too. Just waiting for my 1.8T to blow. 3.7V8 with ITB's and nitrous. Yes please

[ddillenger]

I have 8 matching throttle bodies from a (pair of) CBR1000RR. Should be sufficiently sized....

[tinytim]

The additional torque from this V8 will be more than enough to hold you over when you get it running. It's hard to drive mine "nicely" because it's so much fun.

I like that very much, I can not wait to drive it. Knowing myself... I will want more when I get comfortable with it. I am not planning to do any major performance stuff yet. Maybe a year or so down the road. Built heads with ITBs sounds like quite the set-up. Maniacally it's easy, its the tuning that would be the hard/expensive part.

I have 8 matching throttle bodies from a (pair of) CBR1000RR. Should be sufficiently sized....

Now why did you have to go and say something like that.

[redline380]

Exactly how I feel too. Just waiting for my 1.8T to blow. 3.7V8 with ITB's and nitrous. Yes please

funny you mention that. I recently saw an a8 with a 3.7 badge around town. I had no idea audi ever made a 3.7 v8. I cant imagine they offer much power, though

[onemoremile]

They were in the fwd A8. 32v engines. No real advantage to the 3.6/3.7 over the 4.2 32v. At that point the 40v is pretty close.

[tinytim]

Oh man, those ITBs sound so awesome. Sounds like an angry dog every time he revs it

They still put out 260ish hp/tq... not bad for a 3.7L.

[tinytim]

OK so I got the wiring harness nearly complete. There are a few wires that I am not sure what to do with. Some of the wires from the 4.2 harness to A4 body connection do not have any corresponding wires. I am assuming that its because the A4 has less computers/monitoring/features than the A6 the engine came from. There are also a few wires on the A4 side that I couldn't figure out. Maybe you guys could help me get these few last wires sorted out.

Anything highlighted green are the ones in question. Some are emissions that will be deleted and are marked accordingly. This is a PINOUT matrix for the body plugs only. Columns marked in pink are the corresponding wires to the A4 body plugs.

All of the body plugs from the 2.8 and 4.2 were cut off harness. 2.8 body plugs were then soldered on to the corresponding 4.2 wires as shown on the 4.2 matrix.

4.2 Harness PINOUT


2.8 Harness PINOUT


Any help would be great... this is my last major step, other then exhaust.

[tinytim]

Well today was incredibly frustrating. After a few hours of dealing with a no crank situation, for some reason, the ecu was powering up one of the injectors continuously. Unknown to me, a cylinder was 3/4 full of fuel, when I finally got the motor to turn over... the fuel hydro-locked that cylinder. Snapped the starter right off the block and cracked the end of the starter, subsequently falling into the bellhousing. I have never seen a started break like that, then again I've never had a motor hydro-lock while cranking over. Pulled the motor back out and got all the starter pieces out, everything else looked fine. Still turns over smoothly by hand.

Can't tell by the picture, but the top tab snapped clean off and the bottom tab is bent.


Now I need to figure out the injector issue. Only modification I did to the injector circuit was to splice power to it. I am going to compare the ECU pinout to the harness. I did have to add an additional pin to power up the ecu today, it only had 2 of the 3 power inputs in the plug, kinda strange, I want to trace all of the wires to check things out now.

On a lighter note... had a friend in the shop today... a random pigeon was just flying in and out of the shop... he was helping me:





.

[bhusted]

Wow. That is impressive carnage with the starter. Glad everything still seems to be okay. I wonder if you just have a stuck injector rather than electrical issue. The injector circuit should receive +12v with key on and then the ECU pulses the ground to each injector to fire it. Unless you inadvertently grounded that injector only I would lean more toward it being stuck open.

Also noticed that it looks like you're using the V8 alternator. I didn't feel like I could make the V8 alternator fit, so I'm still using the V6 one. Before you button it all up, check to see if you could change/remove your alternator if you ever needed to.