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Audi RS6 4.2L Swap? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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YOUR RESEARCHAudi RS6 4.2L Swap? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Replace into the 4

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The same generation C5 RS6 bi-turbo (which does not share the same block) can be swapped into the 4.2L C5 motor with the same 4.2L C5 transmission so I assume it can be bolted onto the Boxster transmission as well.
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Audi RS6 4.2L Swap? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Leading evidence: 'Replace into the 4' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace into the 4' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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Use of a larger torque converter

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Suggestion
The RS6 block is different than all of the other Audi V8s in that is was made to accommodate a larger bellhousing necessitated by use of a larger torque converter to handle the torque of the twin turbo V8.
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Audi RS6 4.2L Swap? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Replace into the 4

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Performed · outcome unconfirmed · Original poster
The same generation C5 RS6 bi-turbo (which does not share the same block) can be swapped into the 4.2L C5 motor with the same 4.2L C5 transmission so I assume it can be bolted onto the Boxster transmission as well.
Original post Read captured discussion
Audi RS6 4.2L Swap? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Use of a larger torque converter

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
The RS6 block is different than all of the other Audi V8s in that is was made to accommodate a larger bellhousing necessitated by use of a larger torque converter to handle the torque of the twin turbo V8.
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Audi RS6 4.2L Swap? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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5 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

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POST 1 / ORIGINAL POSTEROriginal post

OK, stay with me here. An audi 4.2L C5 motor will bolt up to a Boxster transmission and is a proven swap. The same generation C5 RS6 bi-turbo (which does not share the same block) can be swapped into the 4.2L C5 motor with the same 4.2L C5 transmission so I assume it can be bolted onto the Boxster transmission as well. Looking on eBay these motors are around $3-4K, and have 450hp out of the box and with a chip can generate 510+hp. Of course a turbo motor is much more complex but still a very cool swap idea. Someone go do this

POST 2Original post

Quotes source post: 609730

OK. You've got my attention. I've read posts that suggest a true just-bolt-on... but am left wondering: is this bolt-on to a manual transmission and/or the Tiptronic? Pardon my ignorance, I don't know everything. Also... I'm assuming there would be some retrofitting? Motor mnounts... moving some electrical and cooling lines? Finally, can the rest of the car handle the 450HP? You know... not torquing the **************** out of anything? Thanks!!

POST 3Original post

Well, first off the block will NOT bolt up to the Boxster transmission. The RS6 block is different than all of the other Audi V8s in that is was made to accommodate a larger bellhousing necessitated by use of a larger torque converter to handle the torque of the twin turbo V8. People that have done manual swaps in RS6s need to use an adapter plate and get a special flywheel, as the RS6 crank has 10 flywheel bolts vs. the normal eight on other Audi engine that have manuals. That is the least of the worries putting one of those in a Boxster. If you have ever seen the packaging of the engine compartment in an RS6, you wouldn't even consider putting it in a Boxster. They are truly nightmarish. It is hard to fit 2.7T in a Boxster. I can't imagine trying to fit an RS6 engine in one. If you want that kind of horsepower, a LS engine would be a much easier and likely lighter swap.

POST 4 / ORIGINAL POSTEROriginal post

Quotes source post: 609746

[Image-only or quote-only post; no author-written text.] https://media2.giphy.com/media/QhCAwDXZ0BltK/giphy.gif

POST 5Original post

Just fit an Audi 2.7t and turn the boost up

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