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911uk

C4s air induction question

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4 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

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YOUR RESEARCHC4s air induction question

Leading reported evidence

Replace exhaust note

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No successful repair reported for this finding.

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Suggestion · Original poster

Will a different air induction kit change the exhaust note on a C4s with PSE, and any idea if it will increase BHP on a car already fitted with X51 kit

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C4s air induction question
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Leading evidence: 'Replace exhaust note' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace exhaust note' (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 sound

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
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Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

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Suggestion

Yes, will definitely change the sound.

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C4s air induction question
Frequently discussed actions (2)

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Replace exhaust note

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 · Original poster

Will a different air induction kit change the exhaust note on a C4s with PSE, and any idea if it will increase BHP on a car already fitted with X51 kit

Original post Read captured discussion
C4s air induction question

Replace sound

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

Yes, will definitely change the sound.

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C4s air induction question
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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.

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

  • 911uk: 1 discussions

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POST 1 / ORIGINAL POSTEROriginal post

Will a different air induction kit change the exhaust note on a C4s with PSE, and any idea if it will increase BHP on a car already fitted with X51 kit

POST 2Original post

Yes, will definitely change the sound. I have a Hayward & Scott PSE-like bypassed exhaust and also tried the 'poor mans' version of the cold air induction kit. It's not a K&N or EVO, but is where you put a cut-down gillete shaving foam cap over the smaller branch of the pipe in between the airbox and the air flow meter (google for 'orange cap', which is the american equivalent and explains it much better than I!). I just wanted to know how it would sound should I go for either the cold air induction kit or the full-on induction kit. Jury's out - sometimes I love it, other times it's just a bit too loud inside the car, especially past 5000rpm.

POST 3Original post

Yes (Well engine note: PSE is on the exit, CAI on the entry) Possibly (not 27 BHP, probably 2-3 BHP, possibly -5 BHP) These things should be viewed as noise adjusters primarily, some can smooth and enhance the airflow (particularly if fitted with a high flow airfilter element - mind the oiled cloth doesn't foul the MAF), some create flow instabilities and extraneous air guide resonance leading to lower entry pressure - think negative AIR RAM)

POST 4Original post

Hi, When I fitted the K&N I noticed a crisper throttle response and a nice throaty induction roar at higher revs. My mate followed me when it had just been fitted and he said it was VERY loud, almost race car like! Can t say I noticed much, if any, power gain though. I haven't had any CEL's and engine runs perfectly.

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