knock retard without logging knock

[nutbag355]

So as the tiles suggests, i was playing around with a mates car on the road the other night for half an hour and i couldnt get the thing to increase spark due to retarding it up to 8 degrees in some spots even though no knock was logged or present got me scratching my head a little. log posted shows it. bin attatched to

shaun3.xdl

(11.77 KiB) Downloaded 244 times

Shauns.bin

(128 KiB) Downloaded 239 times

if anyone is keen to have a look thats be great, probably something ive checked/unchecked or havent checked/unchecked

original bin is "vs_v6_$51_enhanced.v1.4"

cheers

[Wade]

Not burst knock or anything like that?

[nutbag355]

No as there is nothing showing up in the active knock loop. so its not false knock either. thought it may have been torque managment but im unable to increase the timing enough to reach the threshold so unlikely to be that either..

[Wade]

Burst knock is active in this tune and can remove up to 20deg+ of timing

[nutbag355]

so you are suggesting i should set the burst knock retard range to zero?

[Wade]

By the way burst knock has nothing to do with knock. Not in that way anyway. I had a look and it’s set in this bin by default. It’s only set in some bins. What it does is anticipate knock worked off sudden tps increase and automatically removes timing anticipating knock weather there actually is knock or not. Max out the coolant temp to for burst knock and see if it still does it

[nutbag355]

cheers mate ill give that a go next time im in the car.

[bf6379]

I have looked at many of the programs for V6 and V8 Commodores that have knock sensors, but I can't find any parameters that detail the value of spark retard when a knock is detected.
Is this due to deficiencies in all of the xdfs?
Is it listed under some obscure name?
I can find Burst Knock Retard values, but all of them are set at zero anyway.

[immortality]

There should be a scalar for maximum knock retard but how much it pulls out depends on how much knock it detects. Basically it pulls enough timing to get rid of the knock and no more.

[bf6379]

Thanks immortality. After some more research I believe it might be under ESC parameters. The VS V8 Commodore bins that I looked at (BLJX and BMZL) have ESC params - Maximum Retard set to 11.95 degrees.

What I do find strange is that engines running BLJX don't have a knock sensor, but the bin still has the maximum retard value. The knock sensor malfunction flag in that bin is switched off. The BMZL bin is for the 185 kW engine, which does have a knock sensor.

Why would the bin have this value set if it does nothing?