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hi i was just wondering what most people would call acceptable knock levels on a r33 with power fc. fmic and a hks 2535 running 15 pound boost ? since having the power pc fitted and tuned it has been back 3 time s cause of hight knock levels, so my question is how high is too high b4 damage is start to be done cheers dean

Edited by mid life crisis
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When i tune cars i tune them to show no more knock then 40 and then set the engine light to flash at 60 so you know you must back off then.

who is tuning the car for you? where are you ?

hi i was just wondering what most people would call acceptable knock levels on a r33 with power fc. fmic and a hks 2535 running 15 pound boost ? since having the power pc fitted and tuned it has been back 3 time s cause of hight knock levels, so my question is how high is too high b4 damage is start to be done cheers dean

have spoken with the tuner here in sa and it apears to be only recording a high knock level when the car starts to hit the rev limiter. below the limiter it apears ok the engine light is not comming on but the knock level showed up at 73 .normal boosting it seems to be under 30 only peaks when the limiter is hit

hey

when you hit the limiter it will make noise and read high levels. as long as its not doing it on power then it should be ok. I would invest in a soft rev cut for your car like the gizmo rev limiter to help this (which is what i am doing)

Sometimes when i am really agressivly revving the engine to the limiter (massive backfire sound and flames from exhaust) it will read at 100 as well.

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