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Discussion Starter #1
well, caning my engine to 9000rpm may not have been such a great idea. Car doesn't really have increased knock under power, but when spinning freely, I'm hearing this whispering flutter at 3000~5000rpm. Last time I heard this sound, I spun a bearing 9 months later.

Is this a sound others have heard (or am I just paranoid)? Could this be the first symptom of unhappy bearings? If I pulled my engine and replaced the shells with EXACTLY the same ones I put in before, would it be sorted? Or do big ends and crankshaft pins change?

In general, no real increase in peak knock, but the knock graph looks noisier under light to no load, which indicates that the knock sensors are listening to mechanical noise at those times.

My oil system is killer though - I'm at 8.5 bars of pressure when I'm hard on the gas. Tomei pump + extended sump + Accusump. Is it really possible to spin a bearing when the oil supply is more than sufficient??

If I spin a bearing though, might as well do a 2.8 stroker. Am I right in that all I would need are new bearings, a stroker crankshaft, and properly sized conrods, and I can reuse the HKS pistons (sized for stock engine stroke, 87mm bore)?
 

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If I spin a bearing though, might as well do a 2.8 stroker. Am I right in that all I would need are new bearings, a stroker crankshaft, and properly sized conrods, and I can reuse the HKS pistons (sized for stock engine stroke, 87mm bore)?
Depends on the stroker kit I think. I think that one of the kits uses shorter rods and the other uses a higher gudgeon pin. I can't remember which is which though!
 

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cant see it being a bearing in your last case. Not when you heard the noise 9 months before. Maybe 100-200 miles before but i would guess you covered maybe 3000 miles + in the 9 months?
 

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...I have an RB30 sitting in a cubboard at work waiting for my RB26 to expire.

....I'm fine for it to live there a bit longer yet!
 

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Discussion Starter #6 (Edited)
sounds like you need an excuse to drop a 2.8 in there haha
I've got 6000km on this build so I'm not particularly excited by having to rebuild the damned thing again, although 6000km represents over a year of driving for me.

Even still, I wanted 30,000~40,000km out of this engine. Five years. The flutter is getting more pronounced, and only shows up off-load.

Hope it goes away. Rarely, this does happen.

However, I think I'm going to start collecting parts. 2.8 stroker bits. Would be lovely to have a fully built with forgies 2.8 longblock sitting on the sidelines; downtime on an engine failure would be around three days!
 

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I've got 6000km on this build so I'm not particularly excited by having to rebuild the damned thing again, although 6000km represents over a year of driving for me.

Even still, I wanted 30,000~40,000km out of this engine. Five years. The flutter is getting more pronounced, and only shows up off-load.

Hope it goes away. Rarely, this does happen.

However, I think I'm going to start collecting parts. 2.8 stroker bits. Would be lovely to have a fully built with forgies 2.8 longblock sitting on the sidelines; downtime on an engine failure would be around three days!

surely it should have more then 6000 kms life ?

i did 8000 kms in my old cossie a 2.0 4 pot at 2.2 bar 470 bhp and that was as good as ever when i sold the engine.

please dont tell me 6000 kms is the norm for an rb26dett engine :bawling:
 

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Ship it to R.I.P.S

RB30

Job Done!
 
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