PowerFC's "Knock Rating"

[T0nyGTSt]

The PowerFC has a knock sensor or rating when you hook up a hand controller.

Now apparently a 'rating' under 60 is good.

You can expect new cars to have a rating of 10-20.

A car that has done 100,000km might have 30-40.

But danger time (rebuild/retune) is when it hits 50/60.

Can anyone shed light on this?

I was told this applies to N/A and turbo cars (Or anything an FC can hook to).

I'll give you my rating later

T.

[2rismo]

But danger time (rebuild/retune) is when it hits 50/60.

nopers...no way...nuh.... Hardly danger time unless it does it under anything other than full load. 60 isn't anything to worry about as long as you dont hit it all day every day.

80-90 plus is a problem if it's ALL the time.

Adrian

[T0nyGTSt]

My car pulls and 11-12 btw.

Is good???

T.

[two40]

Originally posted by 2rismo

nopers...no way...nuh....  Hardly danger time unless it does it under anything other than full load.  60 isn't anything to worry about as long as you dont hit it all day every day.

80-90 plus is a problem if it's ALL the time.

Adrian

umm, how's 100+? i used to get that on a daily basis.

j/k

although i did get a reading of 110-120 one time. really had the pedal welded though;)

[two40]

Originally posted by T0nyGTSt

My car pulls and 11-12 btw.

Is good???

T.

that's very acceptable;)

[2rismo]

i used to get that on a daily basis.

bastard tells me this after i buy the car from him!!!

lol... 11-12 is great. 100+ a few times on super hot days or with the boost right the way up. doesn't hurt. I also get VASTLY better (read: lower) knock levels when using Evolution 98 fuel. That stuff smacks the ar$e off of optimax, synergy, bp etc...

Adrian

[Gav]

There is nothing magical about the 60 level of the knock sensor except that the PFC flashes the engine warning light if this limit is reached.

From experience I found that at levels of over around 60 detonation was audible via stethoscope (when on the dyno) and over around 100 the detonation was audible from within the cabin (obviously very bad). Personally I liked to keep the knock sensor levels below 30.

On hot days the knock would often increase at certain load/rpm points. I would then isolate those points and advance the ignition (ie move closer to TDC) and/or richen the fuel map around those points.

Takes a bit of trial end error and best done with someone else driving! Also helps to have a predrawn 20x20 grid on a clipboard.

[DJ_L3ThAL]

i find that if i get wheelspin in first and hit the rev limiter i get about 80-90 LOL i guess its the extra noise from the 'bopbopbop' of the rev limiter, otherwise on full load i get around 30s usually, but need to do some more testing