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Hi guys,

Not sure whats going on but on the way home from work this afternoon my powerfc showed a knock level of 65 when it came onto boost. I thought it may have been a one off so i took for another little run to see what it would do and it came up with a level of 73 and the engine light flickered i believe. Car records a knock level of 1 when first started at idle and when off boost around 6. The engine has only done around 15,000k's and is an rb30/25 conversion. I filled up this morning from a shell using there premium fuel and as far as i can recall didnt come onto boost untill i was on my home when the kock level spiked. Any suggestions on what it may be or anything to check?

Thanks in advance,

Matt.

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Hey gfunk,

I am running a cataltic converter. I knocked 4 degrees out of the tune last night and took it for a hard boost and knock levels were fine. According to an experienced friend of mine it indicates the fuel is rubbish. Ill run this fuel out with the timing knocked back and keep the car off boost and fill up with some trusty bp fuel and let you know how it goes. Caltex you break my balls.

Yeah thanks mate. Am planning on using bp ultimate from now on after this incident. Any particular reason why i should use a few more tanks before i put the tune back to normal? Was planning on bumping it up a degree at a time after getting new fuel and giving it a boost and checking levels untill tune is back to normal on the next tank. Im no expert but from what i was told the knock levels i experienced in 2 short bursts yesterday is nothing to worry about in terms of damaging the engine? Of course having those knock levels everyday would be another story.

few tanks means there is no more of the other fuel left, but shouldnt matter much

the knocks wouldnt of done much to the engine, the knock needs to get over 80 to be considered a "true knock"

mine hits 80 one or two times a track day, its not the end of the world :P

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