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Discussion Starter #1
I still have some paranoia regarding my car. I'm past worrying about knocking and det - I've learned how to map and I've got a good strong, yet a touch conservative map, and I'm running 114 octane brew. With a close eye and ear on the engine (plus four knock sensors) I'm satisfied with my tune and the boost I run.

But I find myself worrying constantly about my bearings. A lot. I have spent thousands on my oil system, and as far as wet sump RB26 systems go, I don't think anyone has gone further than I have. I watch oil pressure like a hawk - it is the most prominent gauge on my dash. I fret over oil selection, worried about too thin or too thick.

I worry most about sounds. I've finally determined that my boost solenoid fluttering is just that, the boost solenoid. But any ticking or fluttering sounds freak me out. They are barely audible, considering that I've got uprated cams.

Where I realized that I have a problem though, was yesterday when I was stuck in traffic. Oil temps hit nearly 100, and I started to hear a very soft fluttery sound at low RPM. I panicked and pulled off to let the engine cool down and possibly avert a spun bearing disaster.

Now rationally, 100 degrees is the temperature where an oil actually reaches its rated viscosity. So it's not "too hot". Furthermore, should I be panicking over every peep my engine makes, but even my mechanic can't hear, despite detailed descriptions of what I'm "hearing"?

I've spun a bearing before, and it makes a LOT of noise. I guess what I'm wondering is...is there any way to hear that a bearing is on the verge of letting go?

And what about preemptive reshelling of the whole engine? How would you know when to do that? If indeed that's something that ought to be done? I know that drag Skylines need wrist pins replaced fairly often, especially if they haven't been upgraded to 22mm.

Bearing shells seem like something that would be very simple to lock into place. When rebuilding my engine last year, yeah, they snap into place, but I just stared at the design and wondered why wasn't there something very simple, like locking notches, to really pin them down?

Or how about this question - I've done everything possible I can think of to make for happy bearings - they were sized correctly, they get plenty of oil. I preoil the engine with 2 bars of oil pressure before starting it up. Now, the conrods and crank are supposed to float over, and not ever touch, the bearing shells. So, how can they, or do they, ever wear out? Or have the clearances change over time - which could only happen due to wear? With the mechanism simply spinning, bearings should last forever. But with each piston producing over 100bhp, could that downforce squeeze the oil out and cause some metal-to-metal contact? I do know that a straight-six crank is long enough to flex.

What's the final word on bearings in high-powered RB26s? I know my map is good, that my valves were done right, turbos can be replaced anytime. If I could just trust my bearings, I could really enjoy my car with true peace of mind.

Can anyone give me some sage wisdom from experience? Either to calm me down...or further my paranoia? :p
 

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I know that drag Skylines need wrist pins replaced fairly often, especially if they haven't been upgraded to 22mm.
New one on me.

You worry way too much man.
 

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Chill out dude. If its going to happen its going to happen. The more you worry the less you are going to enjoy the damn thing. Any car makes tons of noises, some of them explainable, some of them just because they are big metal machines.

next you will be tucking it up on a cold night with a duvet and a hot cup of cocoa.

CHILL OUT
 

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Discussion Starter #4
New one on me.

You worry way too much man.
I know - I think I should just condition myself to accept that the ticks and flutters that come out of my engine are normal, although I do have to logically connect them to something - like I'm hearing the valve buckets, or something concrete.

Rob, I'd ask you if you also hear faint fluttering sounds, like thin pieces of metal gently rattling, but I think in your 1000bhp engines there's an enormous racket, considering the power they're set to produce!

The guy who built my engine said that wrist pins will inevitably bend under the cylinder pressures of high-output engines. Hence sizing up to 22m from the stock 21mm. I went through holy hell with him because he said my HKS pins had bent slightly (they were replaced by Tomei pins). Rolling them across the table, I didn't see a thing, but when assembled, the piston would stick a little through it's range of motion. That added a month's delay and eventually aggravation when I supplied (very expensive) Ross Racing pins which he refused to use because they were not sized to metric specs (although they did fit).

But I'd take your word over his - he doesn't build monster drag engines, you do!
 

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chop up your oil filter every oil change and relax lol

how many miles do you have on your build and how many do you expect out of it?
 

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Discussion Starter #6
around 6,000km, I'm hoping for 50,000km (but I expect to go through 2-3 sets of turbos during that time).
 

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Chill out dude. If its going to happen its going to happen. The more you worry the less you are going to enjoy the damn thing. Any car makes tons of noises, some of them explainable, some of them just because they are big metal machines.

next you will be tucking it up on a cold night with a duvet and a hot cup of cocoa.

CHILL OUT
this is brilliant, thank you! I know I'm being a pussy, I needed someone to slap me and man up, stop thinking of the thing as some fragile glass rose, and treat it like the supercar that it is, and give it to her hard the way she was built to take it!!:thumbsup:
 
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