Predator and Headers
04-11-2006 | 05:37 PM
#1
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TECH Fanatic
Joined: Aug 2003
Posts: 1,769
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From: Lexington, NC
Predator and Headers Ill be installing my headers and TD's shortly, heard you will run rich after the install. I am just wondering if I could just use my predator and lean it out until I start to see some detonation then richen it up a bit? Would this be very benificial?
04-11-2006 | 06:38 PM
#2
I wouldn't mess with it unless you have access to someone with a wideband O2.
Just FYI, the stock tune has PE as follows:
0 ~ 3,400 RPM = 11.9AFR
3,400 ~ 5,000 RPM = 11.7AFR
5,000 ~ 5,400 RPM = 11.6AFR
5,400 RPM and greater = 11.4AFR
So theoretically, taking 5% out would lean you out to 12.5~12.6AFR down low. What you can't be sure of is 1) Did the Predator tune lean it out some already? 2) How have my headers affected my tune (ie too rich down low/too lean up top)? AND 3) What is the PCM doing to try and compensate for the new conditions (ie positive LTFTs @ WOT)? There's just too many variables to be guessing, which brings me back to find someone with a WBO2. Don't just guess...
Just FYI, the stock tune has PE as follows:
0 ~ 3,400 RPM = 11.9AFR
3,400 ~ 5,000 RPM = 11.7AFR
5,000 ~ 5,400 RPM = 11.6AFR
5,400 RPM and greater = 11.4AFR
So theoretically, taking 5% out would lean you out to 12.5~12.6AFR down low. What you can't be sure of is 1) Did the Predator tune lean it out some already? 2) How have my headers affected my tune (ie too rich down low/too lean up top)? AND 3) What is the PCM doing to try and compensate for the new conditions (ie positive LTFTs @ WOT)? There's just too many variables to be guessing, which brings me back to find someone with a WBO2. Don't just guess...
