Flash vs altitude
- Thread starter dcnblues
- Start date
No, the narrowband O2 cannot make that much of an a/f difference.
It mainly just monitors and confirms the stock a/f.
It mainly just monitors and confirms the stock a/f.
You are giving the stock O2 too much credit.
It cannot make big changes, only very small.
The flash set up without will run fine at elavation, but, if you live high up, have it dyno tuned high up and it'll run a little better.
No different than taking a newer car, say a 5.0 Mustang, deleting O2's, having it dyno'd in Denver at 5k', the driving over the Rockies at 11k'
It's not going to run fantastic, but it won't harm it either.
It cannot make big changes, only very small.
The flash set up without will run fine at elavation, but, if you live high up, have it dyno tuned high up and it'll run a little better.
No different than taking a newer car, say a 5.0 Mustang, deleting O2's, having it dyno'd in Denver at 5k', the driving over the Rockies at 11k'
It's not going to run fantastic, but it won't harm it either.
it has a barometric pressure sensor, so in theory it will adjust based upon altitude
dcnblues
Registered
Thanks guys! That makes sense.
PS getting bung plugs shipped to California doesn't seem directly possible. FYI. But these seem like they will work:
STAINLESS BROS M12X1.25 O2
PS getting bung plugs shipped to California doesn't seem directly possible. FYI. But these seem like they will work:
STAINLESS BROS M12X1.25 O2
But for sure base adjustments change even in open loop modes, your light throttle cruise fueling is vacuum based which osba delta between map and baro pressure
TonyM995
Registered
I’m not sure where you heard it only makes small changes. I could be wrong but my understanding of the factory narrowband is the closed loop compensation only happens when out of range of what the narrowband reads. So if richer it will try to reduce fuel, if leaner it will increase fuel.
Kinda like the AFR target is all the narrowband can read (14.6:1 - 14.8:1) and all the ecu cares is if the measured reading is above or below that.
They state this more eloquently than I can:
do i need wideband oxygen sensor
rusefi - GPL internal combustion engine control unit - rusefi/rusefi
github.com
I’d love to dig through Suzukis code. The open source ecu I found there is a method that calculates how far off the AFR is and shows if it's within range to not make adjustments. It would seem reasonable Suzuki would do something similar.
rusefi/firmware/controllers/math/closed_loop_fuel_cell.cpp at master · rusefi/rusefi
rusefi - GPL internal combustion engine control unit - rusefi/rusefi
github.com
I’m not sure where you heard it only makes small changes. I could be wrong but my understanding of the factory narrowband is the closed loop compensation only happens when out of range of what the narrowband reads. So if richer it will try to reduce fuel, if leaner it will increase fuel.
Kinda like the AFR target is all the narrowband can read (14.6:1 - 14.8:1) and all the ecu cares is if the measured reading is above or below that.
They state this more eloquently than I can:
do i need wideband oxygen sensor
rusefi - GPL internal combustion engine control unit - rusefi/rusefi
I’d love to dig through Suzukis code. The open source ecu I found there is a method that calculates how far off the AFR is and shows if it's within range to not make adjustments. It would seem reasonable Suzuki would do something similar.
View attachment 1660002rusefi/firmware/controllers/math/closed_loop_fuel_cell.cpp at master · rusefi/rusefi
rusefi - GPL internal combustion engine control unit - rusefi/rusefi
...that is a small change
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TonyM995
Registered
Read my post again. The sensor makes no changes.
Just because the sensor only reads 14.6-14.8:1 doesn’t mean the engine will only adjust within that range.
The atmospheric pressure sensor (that I’ve removed from my bike) reads from 0 - 10,000 ft which means the bike can be run in a wide range of conditions. For that to be possible I’d imagine it will need to make big changes.
I’m here learning and making sense of everything as well.
Read my post again. The sensor makes no changes.
Just because the sensor only reads 14.6-14.8:1 doesn’t mean the engine will only adjust within that range.
The atmospheric pressure sensor (that I’ve removed from my bike) reads from 0 - 10,000 ft which means the bike can be run in a wide range of conditions. For that to be possible I’d imagine it will need to make big changes.
View attachment 1660011
I’m here learning and making sense of everything as well.
You are talking about 2 different sensors, the narrowband O2, vs the barometric pressure sensor, which is making the changes.
The OP was only concerned about the O2's being disconnected, and he is still using the BPS.
TonyM995
Registered
You stated the stock O2 sensor doesn’t make big changes. That’s not accurate. Sensors are inputs- they don’t make changes.
I posted the code from an ecu that’s responsible for reading the O2 sensor and calculating the right amount of fuel in order to achieve the target AFR. The ecu determines the change, not the O2 sensor.
I mentioned the barometric pressure sensor to illustrate that the ecu can and will make big changes. And Greg mentioned how it’s relevant to the OP’s question.
I posted the code from an ecu that’s responsible for reading the O2 sensor and calculating the right amount of fuel in order to achieve the target AFR. The ecu determines the change, not the O2 sensor.
I mentioned the barometric pressure sensor to illustrate that the ecu can and will make big changes. And Greg mentioned how it’s relevant to the OP’s question.
Ok, my failure to word it correctly again.
Of course the ecu is making the changes, not the O2 itself, as it IS only a sensor, I am well aware of that.
The bottom line still remains, the O2's are off, the ecu is flashed, and the bike is still safe to ride from sea level to as high as any passable road will take you.
Which was all the op was concerned about, and the stock narrowband's input does not allow the range of wideband, it has a small range.
@sixpack577 @TonyM995 Thank you for that exchange. Now I understand.
(and thanks for the C code ... ah, memories)
(and thanks for the C code ... ah, memories)
Man I love fuel injection!
I got tired of continually leaning the mixture as the aircraft keeps climbing every couple of thousand feet with the old style float carbs.
Carbs are still an option in your diet
but EFI Lycoming aircraft engines are amazing! The ECU has to calculate for extreme altitude changes and I don't have to do a thing (almost)!! It's pretty much the same thing with bikes etc, but I doubt I'd worry about altitude changes so much as an aircraft because aircraft engines have a very high compression ratio and 100LL fuel.
Density altitude can be overcome with forced induction
I got tired of continually leaning the mixture as the aircraft keeps climbing every couple of thousand feet with the old style float carbs.
Carbs are still an option in your diet
but EFI Lycoming aircraft engines are amazing! The ECU has to calculate for extreme altitude changes and I don't have to do a thing (almost)!! It's pretty much the same thing with bikes etc, but I doubt I'd worry about altitude changes so much as an aircraft because aircraft engines have a very high compression ratio and 100LL fuel.Density altitude can be overcome with forced induction
TonyM995
Registered
And going from lower elevation to higher just means less dense air so the bike would run rich at higher elevation. That’s certainly not going to hurt anything.
Good call that density altitude can be overcome with a turbo. This is why I need a turbo.
I just like to figure out the details of how everything works.
Good call that density altitude can be overcome with a turbo. This is why I need a turbo.
I just like to figure out the details of how everything works.
And going from lower elevation to higher just means less dense air so the bike would run rich at higher elevation. That’s certainly not going to hurt anything.
Good call that density altitude can be overcome with a turbo. This is why I need a turbo.
I just like to figure out the details of how everything works.
You better!
Dot your i's and cross your t's with that fuel tech install, lol.
That's a big first time undertaking, especially on a new bike...but much respect for the effort and ability.
I need to spend more time in the garage but I’ll get to the final harness this weekend. Then I should have every sensor mapped out. The handlebar switches seem a bit more complicated but I just need to figure out what I want each switch to do.
dcnblues
Registered
Thanks again for all the expert commentary. I can now head off to the Wyoming Montana border at will with an easy conscience.
I don't know. Given a choice between a computer-controlled and piloted aircraft or even motorcycle, and one where the basics like air fuel ratio have to be monitored and adjusted by the pilot/rider, I think I would choose option b.
Here's a litmus test. The gearless electric is a little quicker, arguably because the Hayabusa has to shift gears. If you had the option for a CVT Hayabusa, would you take it, or do you prefer manually shifting gears?
I personally don't use the quick shifter much, because I feel it's harder on the transmission than when I use the clutch.
*And oh boy do I hate hate hate the fact that my Japanese sedan with a CVT puts in fake shifts because they have to sell cars to dumb monkeys who are used to the sensation of accelerating more slowly due to shifting. And they don't give you an option to turn off those fake shifts, which I feel would be fairly easy to do.
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