i dunno if this means im running rich or lean its not under load i know it has to be under load to test...but is it rich with high number or lean??
Tuning running rich or lean?? AFR gauge vid
- Thread starter Brin
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Tuning running rich or lean?? AFR gauge vid
i dunno if this means im running rich or lean its not under load i know it has to be under load to test...but is it rich with high number or lean??
This was filmed on idle I assume? It oscilates around 14.7 on idle and jumps around on pressing the gas pedal. This is about right. Below 14.7 is rich, above is lean 
But in all honesty, you should get your homework done about AFR, fueling, lambda correction etc. if you need to ask such a question.
But in all honesty, you should get your homework done about AFR, fueling, lambda correction etc. if you need to ask such a question.
This was filmed on idle I assume? It oscilates around 14.7 on idle and jumps around on pressing the gas pedal. This is about right. Below 14.7 is rich, above is lean
But in all honesty, you should get your homework done about AFR, fueling, lambda correction etc. if you need to ask such a question.
ah right well im running fairly lean then
i took it for a drive and touches 17 at times just short drive without giving it any real boost...even 5th gear cruise off boost its running lean at around 15?? 
When you're cruising or at idle it should be somewhere on around 14.7 it may even be higher (leaner) when you back off the throttle. When you're accelerating/boosting or under load it should be between 11 and 13 (on a turbocharged car), sometimes even lower (richer) ideally.
This will give you a VERY rough idea of how it works:
You want to be to the left or on the left hand side of that flat bit in the middle of the graph at all times (except idle, cruise and backing off). Unfortunately its not really as simple as that graph makes it out to be, the torque moves around a bit under different conditions, with different engines and different fuels. In fact there is nearly an infinite number of varaibles due to hardware and circumstance which is why we need to tune in the first place. And then there is ignition timing which is a whole new ball game.
This will give you a VERY rough idea of how it works:
You want to be to the left or on the left hand side of that flat bit in the middle of the graph at all times (except idle, cruise and backing off). Unfortunately its not really as simple as that graph makes it out to be, the torque moves around a bit under different conditions, with different engines and different fuels. In fact there is nearly an infinite number of varaibles due to hardware and circumstance which is why we need to tune in the first place. And then there is ignition timing which is a whole new ball game.
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As said, it differs, pictures I have seen show 12.5 to be optimal for power.
On top of pictures like this you should also consider fuel addition for cooling effects in turbo applications. I have setup mine for 11.5 at full boost, 12.5 when entering boost. This kills the power I guess, but keeps EGT under control and prevents unwanted knock. This is also what very modern ECUs do. For extreme setups I have heard of people going as low as 10 AFR.
Brin, btw, here is a nice bed time read for you:
http://www.megamanual.com/begintuning.htm
On top of pictures like this you should also consider fuel addition for cooling effects in turbo applications. I have setup mine for 11.5 at full boost, 12.5 when entering boost. This kills the power I guess, but keeps EGT under control and prevents unwanted knock. This is also what very modern ECUs do. For extreme setups I have heard of people going as low as 10 AFR.
Brin, btw, here is a nice bed time read for you:
http://www.megamanual.com/begintuning.htm
Hmmmm, do you have a wideband or a narrow band in your track car. Sounds like a narrow band TBO wideband will hold a figure when you put your foot down that's the whole point.
This is basically the thinking that costed the individual I quoted couple of posts back three engines.
well seeing as my car is set up by the countrys best subaru tuner i think its ok.this gauge is just to be able to see what fuelling is like at a quick glance and tto check no lambda sensor problems.car runs over 300 bhp now and perfect.most peoples tubo cars go bang due to too much boost and poor maintanance not a narrow band gauge being used.
It will have been set up on a wideband anyway, so no panic/problem. It's just that a wideband will give you much more information -- useful if you're tweaking yourself
I think the point Woj is trying to make is a narrow band gauge doesn't give you any useful information on a turbo charged car unless you care about emissions or just like flashing lights. A narrow band will show a rich condition even when a turbo charged car is running dangerously lean. Anyhow Brin was talking about how a wideband should respond and your answer related to how a narrow band would respond which is why I pointed it out.
