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Speed options for the X51

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YOUR RESEARCHSpeed options for the X51

Leading reported evidence

Check with giac if they have the maps worked out

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Unsuccessful attempts: 1
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Suggestion
You will have to check with GIAC if they have the maps worked out for the X51.
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Speed options for the X51

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Leading evidence: 'Check with giac if they have the maps worked out' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check with giac if they have the maps worked out' (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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Replace 3-6 gear rations

Suggestion or failed attempt

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Reported fixes: 0
Unsuccessful attempts: 1
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Suggestion
The other option is to change your 3-6 gear rations which makes a big difference in 50-150 mph accel.
Original post Read captured discussion
Speed options for the X51

Frequently discussed actions (2)

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Check with giac if they have the maps worked out

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
You will have to check with GIAC if they have the maps worked out for the X51.
Original post Read captured discussion
Speed options for the X51

Replace 3-6 gear rations

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 other option is to change your 3-6 gear rations which makes a big difference in 50-150 mph accel.
Original post Read captured discussion
Speed options for the X51

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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.

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

Rennlist: 1 discussions

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Generation: 20261027T011819Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I have an 03 C4S with the X51 motor. I have purchased the new K&N intake (13hp peak, 30 max) and the maxflow mufflers (5 hp peak, 6 max). But this seems to be the end of the possibilities for an X51 motor since anything related to engine management is designed for the stock cams. Any ideas? The car is CPO and I don't want to void the warranty, but I could be tempted...

POST 2Original post

I didn't realize you could get the X51 on the 03C4S, very cool! Other than engine remapping, and better exhaust flow I would say that car is near its' performance potential.

POST 3Original post

A supercharger should fit the bill!

POST 4Original post

Lightweight flywheel and remapping are about all left that is simple. For big $$$ you can swap to a 3.8l X51 or do a stroker kit or supercharger. The other option is to change your 3-6 gear rations which makes a big difference in 50-150 mph accel.

POST 5Original post

Supercharger may work. You will have to check with GIAC if they have the maps worked out for the X51.

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