AFR and E85....What are you aiming for?

[BEATAV8]

Take it to the track and see how it runs there as a baseline. Knock sensor...was I suppose to plug that back in?

Haha I do want to take it out to Byron but it would be soo nice to go with it "set on kill"

 

[Turbo Loyd]

I have compiled the A/F ratios discussed in this thread and put in a file comparing Lambda, and ratios for E-85 and Gasoline in their respective scales. I prefer to use the gasoline scale as this is what most folks refer to. Ideally using Lambda would eliminate the need to specify our A/F ratio scale used. Please note previous translation tables I have uploaded used 9.7 Stoichiometric A/F ratio for E-85 and this table uses 10.0 from the FAST XFI manual.

My hunch is for higher the boost level slightly lower Lambda numbers are needed. That is why I liked the post by Chevota specifying the preferred A/F ratio at 30 psi boost. I have quite a few runs in using 11.5 A/F on the gasoline scale at the 20 psi to 24 psi boost range.

 

[BEATAV8]

"Works well with a wide range of air/fuel ratios"

Loyd's summary seems to back that up!

 

[8 SEC 109]

I run 0.73-0.75 lambda under power. 0.98 idle 0.95-0.92 cruise.

 

[Rafs-T-Type]

I still think anything in the 10's is too fat for E-85. And my lean cruise is around 18:1 with no problems.

 

[Ttype6]

I still think anything in the 10's is too fat for E-85. And my lean cruise is around 18:1 with no problems.

I suspect that your wideband isn't reading correctly.

 

[Rafs-T-Type]

I suspect that your wideband isn't reading correctly.

A possibility, I just heard and read about re calibrating them at the end of this season . How do you verify it's reading correct after re calibration?

 

[BEATAV8]

If you do a free air calibration the sensor and controller will adapt to the known 21% oxygen in the atmosphere. This adaptation is the "calibration".

I verified my configuration by running both the Powerlogger and the Innovate Logworks software at the same time to make sure they both agree.

Mine idles nicely around 12.7 to 13.0, cruises anywhere from 13.5 to 14.0
Around 15.5 or 16 while cruising, mine will start to sputter and miss.

 

[Rafs-T-Type]

Don't they both get the readings from the same place? Thanks for the other tip. I'll do it in spring so I can see/feel if their is a difference in power/smoothness and check the AFR and corrections.

 

[BEATAV8]

Don't they both get the readings from the same place? Thanks for the other tip. I'll do it in spring so I can see/feel if their is a difference in power/smoothness and check the AFR and corrections.

Logworks gets its data from the DB9 connector, part of the sensor controller. Powerlogger gets its data from the analog output, which then goes through a transfer function in order to display what you see on the powerlogger. A loose connection or an incorrect transfer function could make a mess of what you see on the powerlogger screen.

 

[Rafs-T-Type]

Logworks gets its data from the DB9 connector, part of the sensor controller. Powerlogger gets its data from the analog output, which then goes through a transfer function in order to display what you see on the powerlogger. A loose connection or an incorrect transfer function could make a mess of what you see on the powerlogger screen.

But aren't they both getting the data from the same o2 sensor? So isn't it possible they could both read the same incorrect reading? I have three things telling me the same AFR - scanmaster, powerlogger, and T-pro. After some reading there is plenty of people leaning out to where I am (not buicks though). Granted I still plan to re-cal come spring.

 

[TurboBuRick]

The scanmaster, powerlogger and tpro are all reading from the the lc1's anaog output wire.

Logworks connects directly to the lc-1 controller and reads a digital output.

If the sensor is original I would replace it.

RL

 

[BEATAV8]

But aren't they both getting the data from the same o2 sensor? So isn't it possible they could both read the same incorrect reading? I have three things telling me the same AFR - scanmaster, powerlogger, and T-pro. After some reading there is plenty of people leaning out to where I am (not buicks though). Granted I still plan to re-cal come spring.

Yes it all comes from the same sensor, that's what the free air calibration is important for. If the sensor provides a good free air calibration and there are no active faults coming from the controller, then you can more or less trust it to be accurate. There is a somewhat remote chance that the free air cal could be OK, and the diagnostics detect no faults, and the sensor could still be completely inaccurate when registering less than 21% oxygen. Haven't seen that myself yet.

As Rick mentioned, scanmaster, powerlogger, and T-pro all come from the same analog out so they will all show the same number. Best way to check that configuration is to compare it to the logworks number.

 

[Rafs-T-Type]

The scanmaster, powerlogger and tpro are all reading from the the lc1's anaog output wire.

Logworks connects directly to the lc-1 controller and reads a digital output.

If the sensor is original I would replace it.

RL

Is there a certain time span, or mileage you recommend replacing it at? I can't imaging I have more than 6k miles on that sensor and I would think it would live longer in a E-85 car than a gas car.

 

[Ttype6]

Is there a certain time span, or mileage you recommend replacing it at? I can't imaging I have more than 6k miles on that sensor and I would think it would live longer in a E-85 car than a gas car.

Are you reading the numbers on the gauge that came with the wideband,or just the Scanmaster?

 

[Rafs-T-Type]

Are you reading the numbers on the gauge that came with the wideband,or just the Scanmaster?

Scanmaster mainly, but also Powerlogger and T-Pro. The wideband did not come with a gauge.

 

[Ttype6]

Scanmaster mainly, but also Powerlogger and T-Pro. The wideband did not come with a gauge.

When you read the Scanner,the number you see comes from the Powerlogger so they will be the same. The analog output signal can change when it goes into the Powerlogger if the Powerlogger has a different impedance than the wideband controller operates at. If this is so,the output voltage will change as it enters the powerlogger. Since the Powerlogger interprets the voltage,it will show an incorrect A/F ratio if the voltage is incorrect. One way to check this is to buy a gauge and hook it up and compare. The other way it to check the voltage from the wideband output where it is connected to the Powerlogger I/O board. Check the voltage while the wire is connected to the board and compare it to the voltage while disconnected from the board. If they're not the same you've found your problem. If they're not the same,you would need a way to raise (customise) all of the output voltages in the Volts to A/F output curve.

 

[Rafs-T-Type]

When you read the Scanner,the number you see comes from the Powerlogger so they will be the same. The analog output signal can change when it goes into the Powerlogger if the Powerlogger has a different impedance than the wideband controller operates at. If this is so,the output voltage will change as it enters the powerlogger. Since the Powerlogger interprets the voltage,it will show an incorrect A/F ratio if the voltage is incorrect. One way to check this is to buy a gauge and hook it up and compare. The other way it to check the voltage from the wideband output where it is connected to the Powerlogger I/O board. Check the voltage while the wire is connected to the board and compare it to the voltage while disconnected from the board. If they're not the same you've found your problem. If they're not the same,you would need a way to raise (customise) all of the output voltages in the Volts to A/F output curve.

I had TurbobuRick do all the wiring so I'm pretty sure it's good - He does top notch work.

 

[Ttype6]

I had TurbobuRick do all the wiring so I'm pretty sure it's good - He does top notch work.

I'm sure the wiring is good too. This isn't about wiring. Check the voltage on the wideband output while it is connected to the Powerlogger I/O board. Then check the voltage on that wire when it is disconnected from the I/O board. The connected voltage is what the Powerlogger sees. If it is different from the disconnected voltage,the displayed A/F ratio will be wrong. You need to check this.

 

[TurboBob]

the input impedance of the PL is 57K, there should be no loading effects.

B