Tuning questions
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Tuning questions For starters, I already have an LT4 knock module but my mail order tune was not set up for roller rockers, headers, etc.
Is there anything additional I need to do in the tune to make sure I'm not getting "false knock".
I am picking up some knock here and there, and thinking about throwing in some 111 octane and see if it goes away. If it does then I know it was real, if not I'll just tune it out.
Next, I am only pulling a max of 80Kpa at WOT, why is this? I thought it would go to 100. Obviously something is causing it to still pull a vacum, how can I start chasing this down?
Then I am getting 40-41 deg of timing shown on the scanner at WOT, when the tune only commands 38 in the 75-80kpa area for that rpm....
The correction Spark Correction vs MAP vs Coolant Temp is zeroed out in the 80deg C row, and the engine was at 82.3C when I was did the log.
I've attached the datamaster log if anyone wants to check it out.
Thanks for any help,
Greg
Is there anything additional I need to do in the tune to make sure I'm not getting "false knock".
I am picking up some knock here and there, and thinking about throwing in some 111 octane and see if it goes away. If it does then I know it was real, if not I'll just tune it out.
Next, I am only pulling a max of 80Kpa at WOT, why is this? I thought it would go to 100. Obviously something is causing it to still pull a vacum, how can I start chasing this down?
Then I am getting 40-41 deg of timing shown on the scanner at WOT, when the tune only commands 38 in the 75-80kpa area for that rpm....
The correction Spark Correction vs MAP vs Coolant Temp is zeroed out in the 80deg C row, and the engine was at 82.3C when I was did the log.
I've attached the datamaster log if anyone wants to check it out.
Thanks for any help,
Greg
Last edited by gregrob; Mar 2, 2010 at 03:44 AM.
Thread Starter
TECH Senior Member
iTrader: (8)
Joined: Sep 2008
Posts: 5,130
Likes: 4
From: 6,000+ feet
Thread Starter
TECH Senior Member
iTrader: (8)
Joined: Sep 2008
Posts: 5,130
Likes: 4
From: 6,000+ feet
In doing some reading looks like other at my altitude only see 80Kpa max at wot so that makes sense.
That doesnt explain what is modifying the RPM to read much higher than what is commanded. I'll throw up a few screen shots...
That doesnt explain what is modifying the RPM to read much higher than what is commanded. I'll throw up a few screen shots...
Last edited by gregrob; Mar 2, 2010 at 04:08 AM.
try playing with the burst knock tables. bump them up 5% and see what happens. also there is an airflow% differential knock constant table. bump that up some as well. see if the knock goes away. you should adjust the tables one at a time and then log the car to see which one was the culprit if any.
as far as the WOT timing i believe that is a common ocurrence. my car is off about 3degress. others i have talked to have also seen this problem.
as far as the WOT timing i believe that is a common ocurrence. my car is off about 3degress. others i have talked to have also seen this problem.
