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Signman · 06-12-2020, 10:45 AM

You are doing the right thing running closed loop in either mode it will get you in the ball park without loosing a good engine. Watch the correction and adjust the table accordingly until less than 5% then you can run open loop and correct manually if you choose. The reason most don't like closed loop is sometimes the adjustment will slow the car when the table is good. Also remember the processor is making calculations which take time therefore the inaccuracy due to the correction applied later in time at the wrong cell. It's your choice as you become more comfortable.

My advice is to take the car to a good chassis dyno hub or not as long as the tuner is good and familiar with the combo. Doing it at the track will take a lot of runs. You can test fuels determine optimal timing and get the table set to make the most power and be safe in one day. You will still need to tune at the track due the difference in load. The dyno will apply similar load but there are a lot of variables so this is just part of it.

The AFR you end up as optimal will be determined by fuel, air flow/heads/intake, combustion chamber, squish, and the position of the O2 Sensor. The further down the header more lean will be optimal which is why asking for a number from others may not be helpful. Believe it is optimal to have the O2 within 18" of the exhaust valve. Pick the most lean or rich hole checking plugs consider the location for bung placement or run all eight.

Have heard these engines like as much as 13.2 AFR but again this may be dependent on how much fresh air the sensor is seeing which is a reason to not put it in the collector it will work and the car will perform either way. I don't believe the header is not pulling fresh air are high RPM there will always be a small amount and this can be true closer to the exhaust valve therefor the variable on the optimal O2 for your setup.
Also the O2 sensors don't last forever when your data log doesn't look right change it they can last several seasons or several per season. Leaded fuel is a big part of this. Don't drop them or bang anything near them.

06-12-2020, 10:45 AM	#7
Signman Senior Member Join Date: Oct 2003 Location: Lower Slower Delaware Posts: 535 Likes: 22 Liked 269 Times in 99 Posts	Re: 95 LTI Camaro You are doing the right thing running closed loop in either mode it will get you in the ball park without loosing a good engine. Watch the correction and adjust the table accordingly until less than 5% then you can run open loop and correct manually if you choose. The reason most don't like closed loop is sometimes the adjustment will slow the car when the table is good. Also remember the processor is making calculations which take time therefore the inaccuracy due to the correction applied later in time at the wrong cell. It's your choice as you become more comfortable. My advice is to take the car to a good chassis dyno hub or not as long as the tuner is good and familiar with the combo. Doing it at the track will take a lot of runs. You can test fuels determine optimal timing and get the table set to make the most power and be safe in one day. You will still need to tune at the track due the difference in load. The dyno will apply similar load but there are a lot of variables so this is just part of it. The AFR you end up as optimal will be determined by fuel, air flow/heads/intake, combustion chamber, squish, and the position of the O2 Sensor. The further down the header more lean will be optimal which is why asking for a number from others may not be helpful. Believe it is optimal to have the O2 within 18" of the exhaust valve. Pick the most lean or rich hole checking plugs consider the location for bung placement or run all eight. Have heard these engines like as much as 13.2 AFR but again this may be dependent on how much fresh air the sensor is seeing which is a reason to not put it in the collector it will work and the car will perform either way. I don't believe the header is not pulling fresh air are high RPM there will always be a small amount and this can be true closer to the exhaust valve therefor the variable on the optimal O2 for your setup. Also the O2 sensors don't last forever when your data log doesn't look right change it they can last several seasons or several per season. Leaded fuel is a big part of this. Don't drop them or bang anything near them. __________________ Frank Ferrucci I/SA 1271 "Be Thankful for the Gifts You are Given"