O2 sensors with Power Comander V
#11
The PCV operation depends on known/predictable ECU behavior as it works as a delta off of it. Thats one reason you must know what map you are running in the bike along with its state of modification to select the right PCV version. The ECU adjust its behavior based on the O2 sensors, which makes it unpredictable and that makes a mess of the PCV. The PCV is a completely open loop system where it simply makes the best guess based on what works well for most riders, and the O2 sensors must be disabled so they do not interfere with what the PCV wants to do. You can also have a PCV equipped bike professionally tuned.
Since the PCV has no O2 indirect AFR feedback, it has to run very rich to be sure your bike doesn't melt when you happen to load up on the wrong blend. Using the O2 sensor allows you to tune closer to the edge (but not too close) and not worry so much about the fuel, or in other words, to be able to get the most out of the fuel you have (power, mpg).
The much more expensive and optional PCV auto tune modules add broadband O2 sensors back into the mix in an attempt to compensate for fuels as well as other engine modifications. There are several aftermarket products and methods to accomplish this, some better some not so good depending on your situation and skill.
One thing I've never done and will never do is proclaim the PCV as the best tuner for everyone. It has its own feature set just like other tuners on the market and it is up to the rider to determine which features are most important to him. What I'm trying to do here is dispel misconceptions and falsehoods that seem to never go away.
Last edited by iclick; 07-21-2010 at 01:06 PM.
#12
The reason the PCV works best as an open-loop device is because of the limitations of the stock narrow-band sensors, not the PCV. These narrow-band sensors are only able to make very small adjustments to AFRs and if your PCV map applies too much change over the ECM values, which most do, the O2 sensors won't be able to adjust and will likely trip a code.
This is simply untrue. The O2 sensors have little affect on power and act mostly as switches that are able to make only minute changes in AFR values and only at 50% TP or lower. Once you roll-on the throttle, where detonation is most-likely to occur, you are out of closed-loop, so their affect on performance or detonation is minuscule at best. To suggest the PCV is deficient because the lack of O2 sensors will cause the bike to "melt" is completely false. I ran very lean values (up to 14.7:1) in my PCIII and PCV in the cruise range before I upgraded to Auto-Tune and never had a detonation problem. If your bike was tuned on premium and you change to a lower-grade of fuel the O2 sensors aren't going to help you much if any to keep detonation from occurring.
"Much more expensive" is a gross exaggeration, but I'll resist the temptation to go there again in the interest of brevity and to keep OT. Auto-Tune isn't in place to compensate for fuel-quality changes, but exists to keep AFRs to your spec throughout the RPM and TP range. To suggest that retaining the stock narrow-band O2 sensors is a major ingredient toward the goal of a detonation-free or well-tuned bike is simply not true.
This is simply untrue. The O2 sensors have little affect on power and act mostly as switches that are able to make only minute changes in AFR values and only at 50% TP or lower. Once you roll-on the throttle, where detonation is most-likely to occur, you are out of closed-loop, so their affect on performance or detonation is minuscule at best. To suggest the PCV is deficient because the lack of O2 sensors will cause the bike to "melt" is completely false. I ran very lean values (up to 14.7:1) in my PCIII and PCV in the cruise range before I upgraded to Auto-Tune and never had a detonation problem. If your bike was tuned on premium and you change to a lower-grade of fuel the O2 sensors aren't going to help you much if any to keep detonation from occurring.
"Much more expensive" is a gross exaggeration, but I'll resist the temptation to go there again in the interest of brevity and to keep OT. Auto-Tune isn't in place to compensate for fuel-quality changes, but exists to keep AFRs to your spec throughout the RPM and TP range. To suggest that retaining the stock narrow-band O2 sensors is a major ingredient toward the goal of a detonation-free or well-tuned bike is simply not true.
For those that's following this thread, just a quick note that most of the above is the same old school nonsense we have been hearing for years. The assertions and marketing spin have been discredited before but I don't want to take the time to now correct them now.
The PCV working better on late model bikes because of O2 sensor limitations is BS, better that what? What is better? Raw power, simplicity, smooth tune, mileage, street, strip, parked in the garage? The PC brings along its own baggage, but works well enough for a lot of riders.
Those of you that want the truth will find it, but with this kind of unintentional misinformation and distraction around it can be difficult to sift through it all... but I guess it does serve the purpose of discussion.
The OP simply asked why the O2 sensors need to be eliminated and that's simply because the PC converts a bike to completely a open loop system that doesn't work well with the ECU doing any adapting. Completely open loop has its advantages, and baggage.
#13
The PCV working better on late model bikes because of O2 sensor limitations is BS, better that what? What is better? Raw power, simplicity, smooth tune, mileage, street, strip, parked in the garage? The PC brings along its own baggage, but works well enough for a lot of riders.
Those of you that want the truth will find it, but with this kind of unintentional misinformation and distraction around it can be difficult to sift through it all... but I guess it does serve the purpose of discussion.
The OP simply asked why the O2 sensors need to be eliminated and that's simply because the PC converts a bike to completely a open loop system that doesn't work well with the ECU doing any adapting. Completely open loop has its advantages, and baggage.
In summary, I have been reading several of your posts here plugging different tuners advantages and disadvantages. If you have merit (and I don't know), you may want to start putting together some links or cite some definitive sources where they can be verified. There are many times where you make statements that incite others yet you do not produce the facts to back it up. I think that you have some valid points but the way you go about stating your case does not give what you write any credibility. Just my 2 cents.
#15
For those that's following this thread, just a quick note that most of the above is the same old school nonsense we have been hearing for years. The assertions and marketing spin have been discredited before but I don't want to take the time to now correct them now.
The PCV working better on late model bikes because of O2 sensor limitations is BS, better that what? What is better? Raw power, simplicity, smooth tune, mileage, street, strip, parked in the garage? The PC brings along its own baggage, but works well enough for a lot of riders.
Those of you that want the truth will find it, but with this kind of unintentional misinformation and distraction around it can be difficult to sift through it all... but I guess it does serve the purpose of discussion.
The OP simply asked why the O2 sensors need to be eliminated and that's simply because the PC converts a bike to completely a open loop system that doesn't work well with the ECU doing any adapting. Completely open loop has its advantages, and baggage.
The PCV working better on late model bikes because of O2 sensor limitations is BS, better that what? What is better? Raw power, simplicity, smooth tune, mileage, street, strip, parked in the garage? The PC brings along its own baggage, but works well enough for a lot of riders.
Those of you that want the truth will find it, but with this kind of unintentional misinformation and distraction around it can be difficult to sift through it all... but I guess it does serve the purpose of discussion.
The OP simply asked why the O2 sensors need to be eliminated and that's simply because the PC converts a bike to completely a open loop system that doesn't work well with the ECU doing any adapting. Completely open loop has its advantages, and baggage.
#16
The PCV working better on late model bikes because of O2 sensor limitations is BS, better that what? What is better?
Raw power, simplicity, smooth tune, mileage, street, strip, parked in the garage? The PC brings along its own baggage, but works well enough for a lot of riders.
Those of you that want the truth will find it, but with this kind of unintentional misinformation and distraction around it can be difficult to sift through it all... but I guess it does serve the purpose of discussion.
The OP simply asked why the O2 sensors need to be eliminated and that's simply because the PC converts a bike to completely a open loop system that doesn't work well with the ECU doing any adapting. Completely open loop has its advantages, and baggage.
Let's have some discussion. Again, if your points are valid you should be able to put those concepts into words.
#18
What baggage is it's open loop so it can't adjust for altitude changes. What baggage is it's a piggyback unit so you still have the ECM. That creates points of failure not otherwise present. It's a fine product, a quality product. You aren't a fool for using one by any means, but you are blind if you cannot see it has it's disadvantages.
They have room for improvement. Since they are piggybacking off the ECM they could read the calibration off the ECM. I believe the TTS unit does. People do have problems with failures of the connectors and the product itself. They could make a more robust product. Who would complain about the same product at the same price failing less often. That isn't saying they fail so often they are piece of crap, but they do fail and as such they could fail less often. This not your God, this is a piece of electronics plugged into your bike.
I love my harley but, sometimes, I have to wonder just wtf they were thinking. I would love it if they built and all out dragster to go with the V-Rod. Turn? Why would you want to do that? Both on the bike I have and their product lineup there's room for improvement. They have yet to acheive everlasting perfection. Niether has DynoJet or any other company I know of.
They have room for improvement. Since they are piggybacking off the ECM they could read the calibration off the ECM. I believe the TTS unit does. People do have problems with failures of the connectors and the product itself. They could make a more robust product. Who would complain about the same product at the same price failing less often. That isn't saying they fail so often they are piece of crap, but they do fail and as such they could fail less often. This not your God, this is a piece of electronics plugged into your bike.
I love my harley but, sometimes, I have to wonder just wtf they were thinking. I would love it if they built and all out dragster to go with the V-Rod. Turn? Why would you want to do that? Both on the bike I have and their product lineup there's room for improvement. They have yet to acheive everlasting perfection. Niether has DynoJet or any other company I know of.
#19
They have room for improvement. Since they are piggybacking off the ECM they could read the calibration off the ECM. I believe the TTS unit does. People do have problems with failures of the connectors and the product itself. They could make a more robust product. Who would complain about the same product at the same price failing less often. That isn't saying they fail so often they are piece of crap, but they do fail and as such they could fail less often. This not your God, this is a piece of electronics plugged into your bike.
The TTS, SERT and SESPT rewrite the tables on the ECM. This is the main difference between the two products.
#20
I do think he's a sounding-board for Steve Cole, who is the originator of TTS and has been banned from this and other cites for bad behavior. I often wonder if Cole isn't sending him a newsletter every week with talking points, yet Coldcase doesn't seem willing to discuss the topics he raises.
I have never denigrated TTS or any other tuner, as in my opinion all of the flash-based tuners like TTS are a very competent products, but I will respond to claims that are made that IMO aren't in line with fact. As always I invite rational and good-natured discussion.
Last edited by iclick; 07-21-2010 at 01:10 PM.