Is Burst Knock reactive or predictive?
01-09-2005, 12:18 PM
#1
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Is Burst Knock reactive or predictive? Does the computer pull timing on throttle tip-in without ever detecting knock or is it only reactionary and pulls timing after detecting knock?
01-09-2005, 01:04 PM
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Originally Posted by narcszm
Does the computer pull timing on throttle tip-in without ever detecting knock or is it only reactionary and pulls timing after detecting knock?
01-09-2005, 01:25 PM
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Originally Posted by jimmyblue
It pulls based on delta cyl air, before knock (meant to
prevent pinging). Trucks have some bad low thresholds
and high timing pullback values.
prevent pinging). Trucks have some bad low thresholds
and high timing pullback values.
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01-09-2005, 05:10 PM
#8
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Well, it's poorly named, but I'm definitely going to leverage this feature of the PCM. I've got heads that ping instantly on tip-in but do OK in more steady-state condition.
Thanks, guys.
Thanks, guys.
01-09-2005, 05:32 PM
#10
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The more error you have in the VE table the worse off
you will be. If you see your tip-in ping preceded by a
dip in the O2 voltage, as TPS rises, this is showing you
that the speed-density tune (which is exposed on any
changing-MAP event) is too lean.
You can let BK pull spark but you will probably be
better off in the end if you fatten up the VE table at
and about the points where you see tip-in ping.
you will be. If you see your tip-in ping preceded by a
dip in the O2 voltage, as TPS rises, this is showing you
that the speed-density tune (which is exposed on any
changing-MAP event) is too lean.
You can let BK pull spark but you will probably be
better off in the end if you fatten up the VE table at
and about the points where you see tip-in ping.
01-09-2005, 06:16 PM
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98's seem to be the WORST with this, and we can't do anything about it 
.
i just deal with it. im going to try changing to 99+ knock sensors but that may be a little off topic.
let's say you have burst knock enabled. will you see that kr via the scanner or it won't show up unless it pulls more timing than the burst knock is set at. i obviously never messed with this since i can't..
i actually e-mailed hptuners about 98's not having this option (a couple months ago when i was heavy into tuning the car), they said they were going to get back to me, then never did
. it is gonna be a bitch to tune when i decide to spray it...
.i just deal with it. im going to try changing to 99+ knock sensors but that may be a little off topic.
let's say you have burst knock enabled. will you see that kr via the scanner or it won't show up unless it pulls more timing than the burst knock is set at. i obviously never messed with this since i can't..
i actually e-mailed hptuners about 98's not having this option (a couple months ago when i was heavy into tuning the car), they said they were going to get back to me, then never did
. it is gonna be a bitch to tune when i decide to spray it...
01-09-2005, 06:57 PM
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Originally Posted by sleeperstyle
98's seem to be the WORST with this, and we can't do anything about it .
i just deal with it. im going to try changing to 99+ knock sensors but that may be a little off topic.
let's say you have burst knock enabled. will you see that kr via the scanner or it won't show up unless it pulls more timing than the burst knock is set at. i obviously never messed with this since i can't..
i actually e-mailed hptuners about 98's not having this option (a couple months ago when i was heavy into tuning the car), they said they were going to get back to me, then never did . it is gonna be a bitch to tune when i decide to spray it...
.i just deal with it. im going to try changing to 99+ knock sensors but that may be a little off topic.
let's say you have burst knock enabled. will you see that kr via the scanner or it won't show up unless it pulls more timing than the burst knock is set at. i obviously never messed with this since i can't..
i actually e-mailed hptuners about 98's not having this option (a couple months ago when i was heavy into tuning the car), they said they were going to get back to me, then never did
. it is gonna be a bitch to tune when i decide to spray it...
01-09-2005, 08:17 PM
#13
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Originally Posted by Another_User
From what I understand, it doesn't show up on the scanner. And changing the sensors won't make a difference because it isn't really knock. It is expected knock. And if I don't get the option to tune it out, I am going to be really pissed.
01-09-2005, 10:08 PM
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Originally Posted by narcszm
I would think you can see it it the Spark Advance in the scanner. Since the Spark Advance shows the total advance after retard, I'd imagine it contains the burst knock in the calculation.
01-09-2005, 11:14 PM
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Originally Posted by Another_User
And if I don't get the option to tune it out, I am going to be really pissed.
well- it is not an option for 98's, either is kr decay rate... im still pissed about it but nothing i can do.
i mentioned changing the sensors so it will hopefully stop getting tip-in kr (i think it is the overly sensative 98 knock sensors hearing phantom knock).
e-mail the guys at hptuners about it, i'd be happy to back you up. it really sucks not having those options (all 98's don't have them from what i've heard...)
feel free to pm me if you get anywhere with that...
- sorry for hijacking the thread btw...
01-09-2005, 11:45 PM
#16
Every 98 I have seen has knock retard that comes from nowhere. Some speculate overly agressive burst knock tables. On most of them I see it just stays a 4 deg retarded at WOT the whole time and most ride in the low octane timing table. And it doesn't go away with racegas either. Funky PCM.
01-10-2005, 06:25 PM
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Originally Posted by Nic00Z28M6
Every 98 I have seen has knock retard that comes from nowhere. Some speculate overly agressive burst knock tables. On most of them I see it just stays a 4 deg retarded at WOT the whole time and most ride in the low octane timing table. And it doesn't go away with racegas either. Funky PCM.
Sorry guys!
01-11-2005, 03:45 PM
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Originally Posted by Another_User
I tuned out the dreaded 4 degrees. That was easy. All I had to do was wait for the option in the software. Waiting is the hard part. HPTuners kicks ***. I feel bad about even saying I might be pissed...they haven't let me down yet!
Sorry guys!
Sorry guys!
01-12-2005, 05:22 PM
#20
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Wow; burst knock really works. I just made it a little more aggressive and it does a great job pulling a little timing on moderate increases in air flow. You can see that the LS6 VCM is tuned to be much more aggressive on Burst Knock than the LS1. Makes sense given the smaller co chamber on LS6 heads.
