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I hear a faint knocking sound from the engine after 3000 rpm after I accidentally kept it at the 8000 rpm red line on 4th gear for too long as I tried keeping up with the MFD and Apexi PFC commander read outs when doing a test run.

My guess is bottom end damage. ;)

Please advice.

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number 6 big end probaly. Its quite common unfortunatly. The blue R34 (Pics of engine in my sig) was freshly imported and no-one advised the owner of the precautions before tracking it. It lasted two laps of sandown before spinning number 6, it ended up needing a full rebuild as it destroyed the crank.

number 6 big end probaly. Its quite common unfortunatly. The blue R34 (Pics of engine in my sig) was freshly imported and no-one advised the owner of the precautions before tracking it. It lasted two laps of sandown before spinning number 6, it ended up needing a full rebuild as it destroyed the crank.

What precautions are you talking of? Warming up before running/fresh oil etc. or something more?

I've also got a R34 gtr, how much oil should be put in at each change? Literature suggests 4.9L, is that enough???

That sounds about right. I normally fill mine up too the end of the full marked on the dipstick. With consent high revs, alot of oil gets pumped up to the top of the head leaving bugger all in the sump if you run the oil level at the normal full level mark.

Keep it in mind dude.

Oil change and filter, I put in 6-6.5L of oil into the engine (stock capacity sump), only way to reduce the chance of oil starvation when getting into it!. Stock oil pressure gauge doesn't react fast enough, I use an extra aftermarket oil pressure unit.

Ouch, sounds harsh.. Is it a tap sound or a knock? Oil pressure affected, is it worse when cold, comp test done?

Totally different scenario but my old S15 was incorrectly diagnosed with bottom-end damage (similar symptoms, progressively loud rattle above 3k and down on power), when i was sure otherwise. Pulled the cover off and found my cams were chewed out due to poor maintenance , blocked oil lines, etc. Easy fix in the end.

Ouch, sounds harsh.. Is it a tap sound or a knock? Oil pressure affected, is it worse when cold, comp test done?

Totally different scenario but my old S15 was incorrectly diagnosed with bottom-end damage (similar symptoms, progressively loud rattle above 3k and down on power), when i was sure otherwise. Pulled the cover off and found my cams were chewed out due to poor maintenance , blocked oil lines, etc. Easy fix in the end.

^^^ another common issue, we do heaps of sr's and rocker and cam wear is an epidemic in S14 and S15 (early).... the problem stemmed from tight ass owners and dealers using the cheapest oils, they would become claggy and block the oil squirter rail.

Thanks for the tips guys., Opened up the bottom end and noticed conrod bearing # 1 seems to have spun around a few times. Luckily the crank seems fine. Have ordered a set of nismo bearings from nengun which I'll hopefully get in the next couple of weeks. Any suggestions with the running in part?

Thanks for the tips guys., Opened up the bottom end and noticed conrod bearing # 1 seems to have spun around a few times. Luckily the crank seems fine. Have ordered a set of nismo bearings from nengun which I'll hopefully get in the next couple of weeks. Any suggestions with the running in part?

Have you had the crank machined and measured up? what size bearings? looks like next time you'll be picking up engine bits off the road it you don,t do a proper rebuild.

Thanks for the tips guys., Opened up the bottom end and noticed conrod bearing # 1 seems to have spun around a few times. Luckily the crank seems fine. Have ordered a set of nismo bearings from nengun which I'll hopefully get in the next couple of weeks. Any suggestions with the running in part?

Make sure you get it (crank) measured up, usually they will hammer the crank a bit and score it, depending on when it let go it could also be cracked (usually in the radius) or bent (0.03-0.20" ) is not uncommon i have about 6 or 7 bent rb26 cranks here that spun bearings @ 6000rpm and up (i collect fkd engines :blink: )

not to mention you need to pull the whole motor apart and clean it thoroughly to remove the bearing material from everywhere. you are mad if you just chuck new bearings in and bolt it back up again

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