Compatibility between 2000 manual cab and 2004 3.6 motor

Hi, asking for a friend. He has a 2000 cabriolet manual transmission car with a blown motor and has a line on a 3.6 motor from a 2004 car. Supposedly the new motor has the X51 option. The question is, is this still a direct swap? Or is there more involved to make this work? Thanks for any info.

In general not compatible due to different DME and wiring of both the engine and instrument cluster. Variocam vs variocam plus. People have done it but it's not a small project.

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My memory (and refreshed by a trip to Wikipedia) has it that the 996 model ran from 1998 to 2004 (some special models continued on into 2005). While I would expect physically the 2004 3.6l engine would be a drop in swap electronically/electrically I'm not sure. I would worry about the DME in the 2000 MY car being compatible with the 2004 engine and its X51 option. You might visit Pelican Parts and find its section on engine swap white papers (?) and see if you can learn any more.

OK, thanks for the info.

Ahsai brings up the VarioCam vs. VarioCam Plus issue. I had overlooked this specifically but did touch upon it indirectly by my comments regarding the difficulty of the swap from an electric/electronic aspect. If the 2000 didn't have VarioCam Plus and the 2004 does that means the DME will be incompatible and the engine wiring harness too. While one could I guess source the engine wiring harness from the 2004 donor car there's the DME and probably some other wiring related issues as well. That is I'm not sure that just the engine wiring harness would suffice. Thus unless your friend can find high confidence info regarding the ease or difficulty of this swap I think he's probably better off finding an engine from a 996 MY that has the same type of variable cam timing system, VarioCam (sans the Plus), as his car which would probably limit him to 2000 to 2002 MYs, if I had to guess. The book Porsche 996 The Essential Companion covers some of the MY to MY differences which might of some help.

For direct plug-and-play, look for 3.4L 2000 to 2001, which use e-gas and DME 7.2. 2002 to 2004 are 3.6L e-gas DME 7.8 with variocam plus.

Great info, thanks. I'll pass those details along.

Might be worth it to swap the harness and ecu over as well if you have a chance to upgrade.

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You loose Vin if you swap out completely as I understand. Not an easy swap, may as well go V8

I disagree. I've swapped Audi/VW engines into cars 20 years older than the engine/ management systems. Yes, Porsche is different, but they are in the same family. These modules use similar methods to communicate. I could think of at least 2 strong possible ways to do this. Having the chassis be one generation apart would make things easier. Vins can be changed in the ecu as well.

You may be able to do this, but the rest of us .......? To make your assertion a practical proposition it would be very helpful if you could tell us who can do such cyber-surgery and at what cost. Then there is the obstacle of the new generation of Smog machines that detect software changes. We have one at the shop and the short version is that we send cars like this away ! Don't misunderstand, I and most of Rennlisters would love a viable engine swap but most swap proposals fail in the face of the reality of the new Smog machines.If this one is Smog-legal and financially viable ,give us the details ,please. There a a lot of M96 owners who (including me) who would be very grateful for that solution.

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I assume not everyone on this board does their own engine rebuilds either. You would have to pay for this type of solution. The cost would completely depend on the complexity of the project. Every situation would be a little different, and require a different approach. Not all states have the same requirements as far as passing emissions. Keeping the immobilizer active or not, manual, or tip transmission. How far a generation jump between chassis, and engine. What options the car originally came with. The list is long. I am well versed in what is required to legally pass emissions, and what the machines look for. There are also different ways to get a "pass". Some get you a year until the next test date, some get two or more. I own a European repair/performance shop in the Midwest (in house dyno) for the last 15 years, and have helped out many P car owners get their tunes/emission issues sorted. I would be happy to discuss potential solutions if anyone wants, just shoot me a PM.