How to read knock retard
How to read knock retard I am having some issues in reading the knock retard on my truck. What values are typical and how should they be read i.e. volts, degrees, etc. Also, is it possible for autotap to mess up on the readings.
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Re: How to read knock retard It is measured in degrees.
In a perfect world, you'd have "0" degrees of KR. However, that is generally not the case. Some KR is present at WOT. What is normal and what is getting to be too much is a grey area. In most cases, less than 1 degree to maybe 2-3'ish is on the normal side. You start getting over 3 and you're getting a substantial amount.
What really is more important is "NET" timing. That is your total advance minues KR. I've found that my LS1 (as do a lot of 98 LS1's) like's 24-26 degrees of overall "NET" timing. Whether it advances 24-26 degrees on it's own intitial advance or "NET" of KR, it likes that sweet spot. I'd prefer it to be all initial advance, but that's especially hard on a cammed car.
In a perfect world, you'd have "0" degrees of KR. However, that is generally not the case. Some KR is present at WOT. What is normal and what is getting to be too much is a grey area. In most cases, less than 1 degree to maybe 2-3'ish is on the normal side. You start getting over 3 and you're getting a substantial amount.
What really is more important is "NET" timing. That is your total advance minues KR. I've found that my LS1 (as do a lot of 98 LS1's) like's 24-26 degrees of overall "NET" timing. Whether it advances 24-26 degrees on it's own intitial advance or "NET" of KR, it likes that sweet spot. I'd prefer it to be all initial advance, but that's especially hard on a cammed car.
Re: How to read knock retard </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by CMNTMXR57:
<strong> I'd prefer it to be all initial advance, but that's especially hard on a cammed car. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Try dropping your timing at peak torque. With most aftermarket cams the inertial supercharging of the cylinder comes on fairly sudden which can cause detonation with a 'standard' timing table. A reduction in timing between 4400 and 4800 rpm will usually alleviate this problem and allow WOT timing to be taken much higher. If there is not an adequate reduction of timing at peak torque then the motor will detonate from 4400 rpm on up.
Good Luck,
Kevin
<strong> I'd prefer it to be all initial advance, but that's especially hard on a cammed car. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Try dropping your timing at peak torque. With most aftermarket cams the inertial supercharging of the cylinder comes on fairly sudden which can cause detonation with a 'standard' timing table. A reduction in timing between 4400 and 4800 rpm will usually alleviate this problem and allow WOT timing to be taken much higher. If there is not an adequate reduction of timing at peak torque then the motor will detonate from 4400 rpm on up.
Good Luck,
Kevin
TECH Fanatic
Joined: Nov 2001
Posts: 1,355
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From: Chicago (Elgin), IL
Re: How to read knock retard </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by NoGo:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by CMNTMXR57:
<strong> I'd prefer it to be all initial advance, but that's especially hard on a cammed car. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Try dropping your timing at peak torque. With most aftermarket cams the inertial supercharging of the cylinder comes on fairly sudden which can cause detonation with a 'standard' timing table. A reduction in timing between 4400 and 4800 rpm will usually alleviate this problem and allow WOT timing to be taken much higher. If there is not an adequate reduction of timing at peak torque then the motor will detonate from 4400 rpm on up.
Good Luck,
Kevin </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'm not having any problems! Just stating in a perfect world I'd rather have my optimum timing come from all initial advance, not net of KR.
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by CMNTMXR57:
<strong> I'd prefer it to be all initial advance, but that's especially hard on a cammed car. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Try dropping your timing at peak torque. With most aftermarket cams the inertial supercharging of the cylinder comes on fairly sudden which can cause detonation with a 'standard' timing table. A reduction in timing between 4400 and 4800 rpm will usually alleviate this problem and allow WOT timing to be taken much higher. If there is not an adequate reduction of timing at peak torque then the motor will detonate from 4400 rpm on up.
Good Luck,
Kevin </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'm not having any problems! Just stating in a perfect world I'd rather have my optimum timing come from all initial advance, not net of KR.
