There seems to be endless Audi 4.2l options. Is there a year/model you want to stick too? Looking at the horsepower figures an 04 or later is good, an S8 is ideal and I guess the drive by wire or cable decision needs to be made. Am I missing anything? Has anyone attempted to proceduralize the 4.2 swap, even from a high level?

What flywheel and clutch did those of you use that swapped in an ABZ motor? I was hoping I could use the Boxster setup but its an 8 bolt and not a 10 bolt flywheel

This is what i used:

Audi V8 4.2 10 Bolt to O1E/O1A Gearbox | TTV Racing Component Flywheel & Clutch Manufacturers

paid around $500

Used an Audi B5 S4 pressure plate with a 987 Cayman S friction plate in to a 987 Cayman 6 speed box

Do you know if a Boxster pressure plate and clutch plate will work on that flywheel?

The Boxster friction plate will work. Not sure about the pressure plate. Looked kinda similar, but did not try it. Email the guys at TTV - they custom make them, so chances are they will make you one that fits the Porsche clutch if you send them the details.

You are best off looking at the C5 A6 and S6 variants of the 4.2. S6 has forged rods i believe and a better cam setup that makes more high rpm power. The D2 S8 version makes the most power from factory (same upgrades as S6), but uses a different mount setup, which can be swapped to the A6/S6 version relatively easily. The older ABZ works with a standalone ECU, but the stock ECU cannot be easily reprogrammed like the motronic ECU you get in the 2000-2004 cars. The 2004+ 4.2 engines are timing chain rather than timing belt, and require very expensive engine out service at around 100k miles, those would not be good engines for a swap for the most part.

Member AaronF who posted above has the best info I've seen for the swap, here:
https://sites.google.com/view/boxsterv8swap/home

I used an AYS S8 engine with the TTV flywheel P/N 4646 and a B7 RS4 clutch/PP (LUK 02-050). I then worked with stuklr for the tuning side of things. He told me that he has several hours of dyno time with his setup plus he's pretty well known in the 2.7t communities for tuning. He worked wonders for my swap!

Thanks! I'm still trying to make it a better read.

@AaronF - with your 2003, how did you handle the CEL status between the Boxster DME and the cluster? Do you have a constant check engine light or did you do some CAN manipulation?

I just picked up a 2003 986S with a blown motor and am eager to drop in a 2.7t, I’ve got a soft spot for those.

I'm just dealing with the CEL. I'm sure there is some sort of CAN filter that can block the specific CEL setting messagses. I've got an Arduino with a CANbus shield but haven't had time to mess with it yet.

There are several people on our "Swapped Porsche" group on Facebook who could definitely help better than me with the 2.7t swap, Tom Prosser being one.

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Strombomb, would you please document your progress on the engine swap? It would be a very interesting reading, thanks!
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AaronF - Thanks for the explanation. I am thinking CAN shielding/generation/manipulation is in my future. I just invested in a CAN-usb interface and can’t wait to dive in and do some logging... for the purpose of identifying what CAN data needs to be present for a good working system. Also, Tom is awesome. I’ve reached out to him already and his insights are invaluable.

Gilles - Yes I will start a thread after details have been worked out and I have content to share. I can’t wait!!

strombomb - welcome! Please share your progress. I love the 2.7t and daily a b5 s4 but am going with a 4.2 for my boxster as it mostly sees track duty.

My plan running parallel ECUs is to monitor the Audi ECU via OBD2 bluetooth, to a phone and eventually an android tablet running Torque app. Lots of data, as i'm sure you know, available through that route and if the CEL is bothersome you can always just pull the bulb.

Ooh yes, I miss my B5... it was several cars back, now, but I miss it. They are just classic. Definitely some body lines in that chassis that are subtle but timeless.

Are you saying the 4.2 is preferable for reliability or heat reasons making it better suited for a track car? Both my B5 and B6/2.7t suffered from heat soak but were fairly reliable (preventative maintenance and routine inspection it key)... so I partially agree. In this project, I expect intake heat management will again be a challenge... I will probably have to get creative with intercooling.

Are you still planning on the S6 motor? Have you dug into it yet?

Both really. Running my 986 for 4 seasons at our track in Utah has shown me that simplicity is better and that most turbo cars struggle to run well for full sessions during the summer.
As far as heat, i've observed my B5 easily differs 100lb/ft depending on temperature. With the IAT sensor in the intake manifold, even good intercooling only goes so far as when the throttle body is closed it heats up very quickly in there. Still such a fun street motor though, and I won't close the door on putting one in another 986 in the future given the relative low cost of the components.

I actually got an S8 motor and swapped to the a6/S6 mounts and am running a cradle that another member on this board made. I have a shop doing most of the heavy lifting and so far the engine and trans are mounted in the car (in and out several times) and waiting on finishing up exhaust, fuel lines, coolant routing, power steering, and wiring.

For those of you who are running a cable throttle, how did you extend your throttle cable? Seems like a very complex problem, potentially I'll need the Porsche throttle hardware on one side and Audi on the other side...

Rig up an old school linkage if you have a line of sight path from the end of the porsche cable to the TB

What do you mean by old school linkage?

Like this:
https://www.youtube.com/watch?v=8tx_EtTjjro

Can you make a bracket for the end of the Porsche cable and connect a linkage bar to the Audi TB?