My second log on 20 Pounds of boost
Very Slow GS-T
10-15-2004, 02:51 PM
This log is on 20 pounds of boost on a garett 60 trim turbocharger, 255 High Pressure Walbro Fuel Pump, 660cc Injectors, and a Stock Fuel Pressure Regulator.
RPM Timing Airflow O2 1 Bank 1
3536----29------5.51------0.52
3732----27------6.9-------0.86
4004----22------8.93------0.86
4316----19------11.26-----0.88
4688----14------14.85-----0.9
5076----13------18.47-----0.9
5460----9-------20.21-----0.88
5800----14------20.8------0.88
6124----14------21.4------0.88
6432----15------21.75-----0.88
6700----18------21.87-----0.88
6956----16------22.04-----0.88
7148----15------22.2------0.88
7328----16------22.34-----0.88
Does the timing look dangerous or does the timing look fine? Am I going to have to do a boost leak test or can you tell if I have a boost leak from the airflow? If I do have to do a boost leak test, how do I do it or is there a sticky on this forum to tell you how to do one?
RPM Timing Airflow O2 1 Bank 1
3536----29------5.51------0.52
3732----27------6.9-------0.86
4004----22------8.93------0.86
4316----19------11.26-----0.88
4688----14------14.85-----0.9
5076----13------18.47-----0.9
5460----9-------20.21-----0.88
5800----14------20.8------0.88
6124----14------21.4------0.88
6432----15------21.75-----0.88
6700----18------21.87-----0.88
6956----16------22.04-----0.88
7148----15------22.2------0.88
7328----16------22.34-----0.88
Does the timing look dangerous or does the timing look fine? Am I going to have to do a boost leak test or can you tell if I have a boost leak from the airflow? If I do have to do a boost leak test, how do I do it or is there a sticky on this forum to tell you how to do one?
kjewer1
10-15-2004, 04:14 PM
Couple things strike me as odd. The timing is where I expected to see it, but airflow isnt even close. Airflow is low enough that you never hit the highest load map. So I would say you are getting knock. Assuming you are still around -30%, you are really around 28 lbs/mins, but the ECU only sees the 20% after the AFC. This is why tuning with things that modify airflow signals is a pain in the ass ;) O2 voltage is something I almost never go by. But on a 2g I would say you are too lean. With 660s and -30s, you should be quite rich! So something isnt adding up. Is the vac line on your fuel pressure reg still attached? Looks like your getting full boost around 4000 rpm, which is normal.
Add 5% on the AFC "high" map and take another log. Lets see what it does to airflow and O2 voltage.
To do a leak test, there is a vfaq on it.
Add 5% on the AFC "high" map and take another log. Lets see what it does to airflow and O2 voltage.
To do a leak test, there is a vfaq on it.
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