Skids4kids in the mid....not the bum like some Member 609 Member For: 11y 1d Gender: Male Posted 17/09/15 11:11 PM Share Posted 17/09/15 11:11 PM If its in gear under load does it exhibit same signs as revving at idle? Link to comment Share on other sites More sharing options...
HI PSI Member 1,572 Member For: 17y 10m 30d Gender: Male Location: Central Queensland Posted 17/09/15 11:46 PM Author Share Posted 17/09/15 11:46 PM If its in gear under load does it exhibit same signs as revving at idle?Yes, it exhibits the same symptoms when under load. Link to comment Share on other sites More sharing options...
JETURBO ...JD TUNING ADELAIDE... Gold Donating Members 23,708 Member For: 15y 10m 24d Gender: Male Location: Adelaide Posted 17/09/15 11:57 PM Share Posted 17/09/15 11:57 PM The engine ran for three days, before the intake valves smashed into the pistons and cracked the head casting. ^^^ why did this happen ? ^^^ What base tune is in the car ?What cams ?How much crush ?And VCT is 100% locked out ? ( so not working ) What * were they locked to ? Link to comment Share on other sites More sharing options...
HI PSI Member 1,572 Member For: 17y 10m 30d Gender: Male Location: Central Queensland Posted 18/09/15 12:25 AM Author Share Posted 18/09/15 12:25 AM The engine ran for three days, before the intake valves smashed into the pistons and cracked the head casting.^^^ why did this happen ? ^^^What base tune is in the car ?What cams ?How much crush ?And VCT is 100% locked out ? ( so not working )What * were they locked to ?I think, that it is best that I stand aside here, as Daryn is best qualified to answer these questions. I believe that his reply will be some time this afternoon. 1 Link to comment Share on other sites More sharing options...
HI PSI Member 1,572 Member For: 17y 10m 30d Gender: Male Location: Central Queensland Posted 18/09/15 12:28 AM Author Share Posted 18/09/15 12:28 AM Please keep the questions coming........ Link to comment Share on other sites More sharing options...
JETURBO ...JD TUNING ADELAIDE... Gold Donating Members 23,708 Member For: 15y 10m 24d Gender: Male Location: Adelaide Posted 18/09/15 12:41 AM Share Posted 18/09/15 12:41 AM Yeh lets guess every possible situation until we get an answer Or How bout some further info as a solid base suggestions are out there already Link to comment Share on other sites More sharing options...
HI PSI Member 1,572 Member For: 17y 10m 30d Gender: Male Location: Central Queensland Posted 18/09/15 12:50 AM Author Share Posted 18/09/15 12:50 AM Yeh lets guess every possible situation until we get an answerOrHow bout some further info as a solid base suggestions are out there already I am not shirking your questions. I have no knowledge of these, so I have asked the owner to supply this information. He will reply to them this afternoon..Like many of us forum members, he is a very busy man. I am just trying to cover more potential sources, and have more questions waiting for him. 1 Link to comment Share on other sites More sharing options...
WTFWSAT New Member 17 Member For: 10y 3m 29d Posted 18/09/15 03:51 AM Share Posted 18/09/15 03:51 AM This is very similar to the conclusion we've come to. Something completely unrelated to the timing chain is causing a harmonic and it just happens to be that the timing chain is what is turning the vibration into a noise and thus, creating the allusion that the timing chain is the issue. When you are standing in front of the car and it makes the noise, you'd swear it was the chain rubbing on the tappet cover, but it's not. I'm 100% sure it's not rubbing anywhere. We really appreciate everyone's input on the matter and we're just hoping someone has witnessed a similar situation and it can be an easy fix before we pull the engine down completely and start again. I should have started the thread myself but didn't want it to look like I was defaming the engine builder but it appears everyone knows who we're talking about anyway. Auto or manualWe had a similar noise with our Nizpro engine in exactly the same rev range. There seems to be a resonance at that RPM that amplify noises. For us it ended up being exhaust related , but took ages to diagnoses as it definitely appeared to be coming from the engine. SO this noise may NOT be actually coming from the engine. Noise travels strangely through different components and metals.Very hard to diagnose from the short video. Link to comment Share on other sites More sharing options...
WTFWSAT New Member 17 Member For: 10y 3m 29d Posted 18/09/15 04:04 AM Share Posted 18/09/15 04:04 AM The engine ran for three days, before the intake valves smashed into the pistons and cracked the head casting. ^^^ why did this happen ? ^^^ What base tune is in the car ?What cams ?How much crush ?And VCT is 100% locked out ? ( so not working ) What * were they locked to ?The timing chain jumped teeth due to the tentioner failing. (Not naming brands but it wasn't a cheap tensioner) It's now a solid tensioner so it can't fail again. The tune is the same as when it came off the dyno last time. Although we did have to pull quite a bit of fuel out of it to make it idle properly with the new head. Cams are "very big". Maybe 310degrees of duration and 15mm lift. I can't recall exact specs at the moment. The only thing that has really changed from before to now is the head casting. There was no hint of the noise previously, but now it's very audible. The video doesn't do it justice. It's not good. All the lash adjustments are right, can journal clearances are right, the sprockets have all been replaced and have been checked to make sure they're running true etc. thanks for your input. Link to comment Share on other sites More sharing options...
JETURBO ...JD TUNING ADELAIDE... Gold Donating Members 23,708 Member For: 15y 10m 24d Gender: Male Location: Adelaide Posted 18/09/15 04:37 AM Share Posted 18/09/15 04:37 AM A solid tensioner ?So no hydraulic fluctuations......I bet at a specific rpm your chain/guides have a harmonic spazz and the tensioner is passing that onto the timing chain cover and areas Swop it out for a stock item ( its quick enough to do ) and see what happens Link to comment Share on other sites More sharing options...
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