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tatasta
June 30th, 2009, 11:52 AM
Hey,

I've been trying to get rid of this KR in the 2000 to 2600 RPM area. I've made some changes to Burst Knock in B6210 Air mass delta and lowered sensitivity and spark. I'm running good fuel. I don't get any KR @ WOT but this one to two degrees in the 2000-2600 RPM area is kickin' my ass.

Thanks

http://i625.photobucket.com/albums/tt334/tatasta/KR2bmp.png

http://i625.photobucket.com/albums/tt334/tatasta/KR1.png

Aloicious
June 30th, 2009, 06:48 PM
Hey,

I've been trying to get rid of this KR in the 2000 to 2600 RPM area. I've made some changes to Burst Knock in B6210 Air mass delta and lowered sensitivity and spark. I'm running good fuel. I don't get any KR @ WOT but this one to two degrees in the 2000-2600 RPM area is kickin' my ass.

Thanks


I had a simmilar issue a while back in the exact same range, it ended up simply being the spark table. I don't have my tuning computer with me, but I'd say return the knock sensitivity to normal, lower the specific cells that the KR is happening in around 1-2* more than the KR that is happening, then lower all the adjacent cells around 1/2 as much than that to smooth the spark transision between cells and as a safety net to prevent the KR.

if I understand it correctly, Burst Knock doesn't actually appear as KR in a log, so that wouldn't have any affect on the KR you're getting.

whatever you do, I'd DEFINANTLY return the knock sensitivity to where it is stock, lowering that is simply crippling something that is there to protect you. you need to attack the cause of the KR, not how it is reported.

joecar
July 1st, 2009, 03:21 AM
+1.

BTW: you can set more display digits on your wb afr by doing rightclick->properties->series->series 4 and change format from "%.1f" to "%.2f".

tatasta
July 1st, 2009, 02:48 PM
+1.

BTW: you can set more display digits on your wb afr by doing rightclick->properties->series->series 4 and change format from "%.1f" to "%.2f".

Thanks. I will adjust those settings. Also, I did find a problem in my spark table. Kind of embarrassed that I did not notice it before. It was not like a mountain but was obvious enough.

Also, I am using Photobucket but still can't get my images to post clearly. Anything you see I am doing wrong??

Thanks again!!

mr.prick
July 1st, 2009, 03:33 PM
Images are clear to me.

Aloicious
July 1st, 2009, 03:47 PM
Images are clear to me.

yeah I can see them they look fine to me too.

tatasta
July 2nd, 2009, 09:10 AM
Ok, thank you.

joecar
July 2nd, 2009, 02:54 PM
Images are good and clear.

Knock is a difficult problem, especially at low speed medium-high load... try subtracting 2-4 degrees from those areas.

Aloicious
July 2nd, 2009, 03:06 PM
Images are good and clear.

Knock is a difficult problem, especially at low speed medium-high load... try subtracting 2-4 degrees from those areas.

+1

although I'd return the knock sensitivity to stock settings first though. because if you desensitized it and your logs are showing 1.8*, it may actually be much more than that depending on how much you lowered it.

do a log with the KR sensitivity at normal stock settings and lower the cells KR is happening in 1-2* more than your KR amount. then lower all the adjacent cells 1/2 as much. that has always worked very well for me.