LSJ KR on throttle up transition...

[BADSZ28]

No idea why. Seams to be the only place it does it is when I am off the throttle then go into it. Whether hard or smooth, there is KR. I attached latest tune and log.

[BADSZ28]

Should probably note this is for a 2006 Cobalt SS Supercharged.

[383_Stroker]

Sounds like tip-in knock.. which we don't have a table to adjust.

[BADSZ28]

Is there a way to reduce it? I don't think I have too much timing in there. I basically modeled my timing tables from the GM Stage2 tune. Not agressive at all. And it has the stock pulley.

[dont_blink]

Sounds like tip-in knock.. which we don't have a table to adjust.

Yes we do. It's called burst knock. There should be a table for retard vs. cyl airmass delta, with transitions from .01-.20 I think.

[BADSZ28]

I did see that and made some adjustments. But it did not seam to help. Anyone have a table I could try? Not sure how aggressive I have to be to see results. And I want it to be safe.

[383_Stroker]

Yes we do. It's called burst knock. There should be a table for retard vs. cyl airmass delta, with transitions from .01-.20 I think.

Lol.. thanks for the fix..

well.. then.. what is tip-in knock?..

[jimbos'ss]

click

[dont_blink]

Lol.. thanks for the fix..

well.. then.. what is tip-in knock?..

Same thing. Just different name on a different vehicle.

[383_Stroker]

Same thing. Just different name on a different vehicle.

whew.. thought i was going crazy

[omega_5]

Maybe I'm getting my terminology mixed up.... but I always classified 'tip-in knock' as low end knock due to abrupt throttle changes.... where as 'burst knock retard' is the PCM's timing retard system used to prevent actual knock. In other words; tip in knock is the engine actually knocking, but burst knock retard is preventing knock.

Either way... in an LSJ, they will read the same as we don't have separate KR PID's.

[BADSZ28]

Can someone give me a table that works for them?

[dont_blink]

No. Every car is different based on cylinder wear, spark plug gap, spark plug type, spark plug erosion, effective compression ratio (decked head, non-stock gasket, etc), in coming air temp, density, intake runner wall fuel saturation, total air flow, everything. When we are talking about .02 g/cyl, those little tiny things all matter for low end timing. You need to set it up for your own vehicle. No one in this world has or can make a table for you car that works perfect unless they spend hours doing it themselves with your car in all different scenarios.

[BADSZ28]

No. Every car is different based on cylinder wear, spark plug gap, spark plug type, spark plug erosion, effective compression ratio (decked head, non-stock gasket, etc), in coming air temp, density, intake runner wall fuel saturation, total air flow, everything. When we are talking about .02 g/cyl, those little tiny things all matter for low end timing. You need to set it up for your own vehicle. No one in this world has or can make a table for you car that works perfect unless they spend hours doing it themselves with your car in all different scenarios.

I understand all this. Just trying to get some direction. Do I adjust 10% at a time, 50%...