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Discussion Starter · #1 ·
I freely admit that 99% of my posts here are about being a complete hypochondriac about my car. So, with that disclaimer said...

A couple months ago I tested my car with a 9500rpm rev limit. Performance was pretty crazy, but I don't think it was too healthy. Since then, I have noticed a barely perceptible rise in noise from the head, and an average rise of 3-5 on the Power FC knock meter, with a more jagged curve off load (which usually indicates mechanical noise versus actual knock).

It's easy enough to pull the cam covers off and have a look. Any pointers on what to look for, other than just sticking feeler gauges in and checking bolt torque for the cam cradles?
 

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Discussion Starter · #3 ·
eeap. so if a particular cam lobe is marked up, then that valve is out of whack...meaning head-off to sort the bucket, shim, or retainer...d'oh.
 

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eeap. so if a particular cam lobe is marked up, then that valve is out of whack...meaning head-off to sort the bucket, shim, or retainer...d'oh.
well, yeah, if you have a uniform marking on all lobes then i would just put that down to wear, but like you say, if you have one specific lobe marking or anomaly then you have a tappet issue.

also toby, bearing in mind your paranoia, are you sure you do have a NOISIER head or are you just expecting to because you rev'd high a few months back??

kev-san:thumbsup:
 

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Discussion Starter · #5 ·
noise level is higher, but truth be told, it's still very quiet compared to a lot of other RB26s and only appears when the engine is very hot.

Could just be one of those things, not worth dealing with until the engine gives out. Some engines are just noisy - mine was really done up very tight and other than normal piston slap when icy cold, never made much of a peep. I'm half-whining really, because my engine knock readings are still under 30. I just make note of it because if the engine is properly warm and I go full boost, I might see 25-26, but if the "noise" is there, then while lifting or off load, I'll see 28~30.

Just occurred to me that maybe I might want to check my crank damper as well, make sure that's torqued on and that the woodruff keys are good and tight. Crank flex can make everything inside the bottom end rattle a bit I think.

(what I really ought to do is take all my gauges and bin them. If I didn't have all this information, I'd think my car has been running dead perfect since it was finished in Summer 2008....)
 

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at the risk of sounding like a pillock, what exactly are knock readings? what is knock?

kev:thumbsup:
 

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Discussion Starter · #7 ·
I obsessively read the knock readout on my Power FC Commander, and that ten-second graph, looking for clues about the engine's "health" like reading tea leaves. I really ought to just drive and just use the idiot lamp warning. It's a slow weaning process however. I disconnected the backlighting to my gauges (only the needles are lit) so if I really want to see what's going on (I drive 90% at night) I can, but I don't stare at them.

<signed> Gauge Addict
 

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I obsessively read the knock readout on my Power FC Commander, and that ten-second graph, looking for clues about the engine's "health" like reading tea leaves. I really ought to just drive and just use the idiot lamp warning. It's a slow weaning process however. I disconnected the backlighting to my gauges (only the needles are lit) so if I really want to see what's going on (I drive 90% at night) I can, but I don't stare at them.

<signed> Gauge Addict
thats nice toby, but what is knocking?:sadwavey:
 

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thats nice toby, but what is knocking?:sadwavey:
I think the knocking that Toby is referring to is the knock sensor... It is suppose to detect det.
 

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Discussion Starter · #11 ·
no det in my engine; I've got det cans for that and of course have a listen quite often. And of course I've got two additional knock sensors on top of the two stock ones; all were replaced with new units about 10,000km ago.

Knock, ping, det, preignition....they all mean the same thing: fuuuuuuuck me I've got to rebuild the engine!!
 
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