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M96 3.8L Motors - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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YOUR RESEARCHM96 3.8L Motors - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Use 997 3.8 head gasket

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Unsuccessful attempts: 1
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Suggestion
My motor started life as a 3.6 (96mm bore with 82.8mm crank) and was sleeved with Nickies out to 99mm (so the 3.6 became a 3.8), and uses the 997 3.8 head gasket.
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M96 3.8L Motors - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Leading evidence: 'Use 997 3.8 head gasket' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Use 997 3.8 head gasket' (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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Frequently discussed actions (1)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Use 997 3.8 head gasket

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
My motor started life as a 3.6 (96mm bore with 82.8mm crank) and was sleeved with Nickies out to 99mm (so the 3.6 became a 3.8), and uses the 997 3.8 head gasket.
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M96 3.8L Motors - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

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

986Forum: 1 discussions

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POST 1 / ORIGINAL POSTEROriginal post

Anyone know if there's a group that has done much re-working of those motors? I know Flat 6 Innovations has had great success taking the 3.2 motor up to 3.6, but I haven't really heard of anyone starting with one of the 2005-later 3.8 Carrera S motors as a starting point. I am wondering if the 3.8's are already pretty much maxed out right out of the gate?

POST 2Original post

The 3.8 is actually an M97, not an M96. LN could certainly sleeve it if you wanted Nickies, run JE pistons, R&R or Pauter rods, LN upgraded IMS assembly, oil system mods, etc. I don't know for sure, but there MAY be room to punch out the bore a hair more than the 99mm it already is. My motor started life as a 3.6 (96mm bore with 82.8mm crank) and was sleeved with Nickies out to 99mm (so the 3.6 became a 3.8), and uses the 997 3.8 head gasket. Not sure if the M97 really is any better or if it's just a function of the small sample size, but you don't seem to hear about 3.8s blowing up....

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