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I have an issue with my Power FC showing a knock on gear changes. Normally there is no problem with detonation, the most it will display is maybe 10 on the graph. However when you go for the next gear there is a spike on the display, sufficient sometimes to make the warning light flash.

If anyone could help with the following:

Is this normal?

Is this anything to worry about?

Are there settings other than the 20x20 maps that can be adjusted?

Should I be looking at the BOV's (Apparently not standard, but plumbed back. In my defence I didn't change them, it came like that)

Setup is on an RB26DETT with 13lb boost, exhaust & not much more.

Any help would be appreciated

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I have an issue with my Power FC showing a knock on gear changes.  Normally there is no problem with detonation, the most it will display is maybe 10 on the graph.  However when you go for the next gear there is a spike on the display, sufficient sometimes to make the warning light flash.

If anyone could help with the following:

Is this normal?

Is this anything to worry about?

Are there settings other than the 20x20 maps that can be adjusted?

Should I be looking at the BOV's (Apparently not standard, but plumbed back.  In my defence I didn't change them, it came like that)

Setup is on an RB26DETT with 13lb boost, exhaust & not much more.

Any help would be appreciated

The knock level warning is adjustable, have a look at the Commander when the dash warning flashes. That will tell you how big the problem is. If the warning is set at 30 and it goes to 31 then don't worry, if it goes to 90 then I would be looking for a reason. You should also note that the dash warning light comes on for other reasons than knock. The Commander readings will tell you what it is.

We get dash warning flash due to the rpm limiter (ignition cut) and, as meshmesh suggested, when the twin plate clutch rattles.

Hope that helps

Thanks for that fellas.

Unfortunately I dont have a twin plate clutch, but I do have some lovely fluffy dice.

It is not the engine buzzing to the red line as the light sometimes comes on when you back off as well as when you change gears. I'm fairly sure I wasn't pulling 8 grand in fifth....

I will check the thresh hold for the knock sensor, but am pretty confident it will be whatever Apexi set it up for at the factory, which I think is about sixty.

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