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[hrdtail78]

Mayor,

Lets take WOT out of the pic.  Easiest thing to tune for several reasons.  On a decent combo, not max effort or even great combo.  Just a decent one.  You will have a positive pressure in the pipe.  Pressure is equal to 90 degrees of the surface.  Doesn't matter if it is in the pipe or going through a small hole to a block, and then being sampled.  Easiest way to prove this is talking about a DJ sensor with Herko block.  1. you have access to this system, 2. Herko blocks need a vacuum source.  Hold 100% throttle at 4500 rpm.  Toggle pump on and off.  AF doesn't change.  Do same test at 1250 and 7% throttle.  AF will change.  W/out a vacuum dependent block.  The lead hose can be disconnected.  Same can be seen.

My concern on BB vs NB will always be lighter kpa loads.  For reasons the chart shows, but that isn't my biggest concern.  It has been discussed before about the tolerance of AFR these thing will run on.  My biggest concern is polling and sample rates.  At what crank position does DJ poll it's sample?  Is it the same crank degree every time?  Is it the same frequency (samples per second) at 1000rpm as it is for 3000rpm?  We are dependent on an averages at lower kpa's.  I hope that average isn't low because it averaged data after the slug of air passed, or before it got to the sensor.

NB sensors poll at a known position of the crank.  Not trying to convince you of anything.  Just trying to bring some things up for discussion.

[hrdtail78]

Steve, I'm referring to vtuned (TTS) or basic tuned (Power Vision) narrow band tunes in the 75-80+ kPa and extended cells in lambda based calibrations. 

IME I have found the opposite.  BUT I have also seen CLB (or target lambda) tables come into play.  Program blending or hand blending.

[mayor]

if very heavy load up until wide open is thrown out of the discussion, then I tend to agree that narrow bands and broad bands are 6 of one, half dozen of the other. 

My concern on BB vs NB will always be lighter kpa loads.  For reasons the chart shows, but that isn't my biggest concern.  It has been discussed before about the tolerance of AFR these thing will run on.  My biggest concern is polling and sample rates.  At what crank position does DJ poll it's sample?  Is it the same crank degree every time?  Is it the same frequency (samples per second) at 1000rpm as it is for 3000rpm?  We are dependent on an averages at lower kpa's.  I hope that average isn't low because it averaged data after the slug of air passed, or before it got to the sensor.

NB sensors poll at a known position of the crank.  Not trying to convince you of anything.  Just trying to bring some things up for discussion.

I share the same concerns.  I think there is an advantage of the narrow band report speed, and I see a huge advantage with a tuning system that ties the ecm into the sample time.  The later is why I would like Steve to try to incorporate an analog BB sensor input into the Data Master/Vtune program. I'm sure that the report speed of the BB's may not allow that to work though.   

I'm not feeling like you're trying to convince me of anything, I enjoy the discussion.  I also value your opinion.  Same goes for Steve. 

Steve, I'd actually settle for dual non scaled  0-5v inputs...if the scaled option was too tough.    

[Steve Cole]

The problem is trying to compare apples and oranges. When people are lead to believe or think they know that Narrow bands will not measure this that or the other thing, when the truth is they have little to No idea what they can do. My whole point has always been the same and that is simply that the Broad Band systems on the market today are not capable of even coming close to what is claimed. The Broad Band sensor is capable of being much better BUT due to how they are being used they are not. So if the poor range they have today, due to the misuse of them, is good enough, that's fine.

Now if you take a simple Narrow Band sensor and use it, it cannot measure the entire range of a Broad Band can do. If we take the range that we need for most internal combustion engines running gasoline we DONOT need the entire range of a Broad Band sensor. A Narrow Band can and will do the job well enough! Not as well as a properly used Broad Band can, but, well enough for the applications we are talking about and as well as the way Broad Bands are being used today.

Another little missed fact is that the response time of a Broad Band sensor is ~280 Ms once up to operating temperature, that's as fast as it can respond and there is not a damn thing you or I can do about it! So that gets you 3.57 samples per second MAX. As they age or measure richer mixtures that slows some more.  An engine fires each cylinder 8.333 times per second at 1000 RPM, so a Broad Band gets you (8.333/3.57) 2.33 engine firings per sample taken at 1000 RPM. Now let's look at 6000 RPM! That's 50 engine firing cycles per second, so (50/3.57) 14.00 engine firings per sample taken. So a little simple math shows you just how much your not seeing!

A heated Narrow Band sensor up to temperature is ~10 Ms today! So that gets you 100 samples per second MAX. In the HD case the sensor is read once each and every firing cycle at the same place in crankshaft position each time. So, An engine fires each cylinder 8.333 times per second at 1000 RPM, so a Narrow Band can get you (8.333/100) 0.083 engine firings per sample taken at 1000 RPM. Now let's look at 6000 RPM! That's 50 engine firing cycles per second, so (50/100) 0.5 engine firings per sample taken. Since HD has limited it to once per engine cycle it's easy to see the sensor response is not at issue at all with the Narrow Bands like it is with Broad Bands.

So with this information which would you want to be using?

[mayor]

So with this information which would you want to be using?

simple answer, both.  I see no need to limit to just one. They both have their strong suits, and they both have their weaknesses. 

I think that you make a valid point that narrow bands are faster, but in reality once you get above 4,500 rpm or so the need starts to exist to read outside the typical NB operating range. Let's take your 6,000 rpm example.  How often is a HD motorcycle operated at the rpm below ~80 kPa?  That same question applies to 5,000 rpm as well. 

[Steve Cole]

You seem to have your mind frozen and do not want to understand what I posted above. A HD naturally aspirate engine is in no way going, or needs to go, outside of what a Narrow Band can read. You keep repeating that over and over again and your wrong. I do not know how else to say it. While the Narrow Band sensor is not as accurate as it is at say 14.7 it still reads 13.0 as well as a Broad Band does. It also does it as accurately as the Broad Band does as they are being used today by the aftermarket gauges that are being used.

In your stated example using you TS Broad Band unit your data is no better than and possibly worse than what you can get today from the Narrow Bands that are already there and as a matter of fact your TS unit is giving you an average reading of what the engine did over some 14 engine fire cycles at best.  When the Narrow Bands can and do give you a reading from each and every engine cycle.

[mayor]

You seem to have your mind frozen and do not want to understand what I posted above. A HD naturally aspirate engine is in no way going, or needs to go, outside of what a Narrow Band can read. You keep repeating that over and over again and your wrong. I do not know how else to say it. While the Narrow Band sensor is not as accurate as it is at say 14.7 it still reads 13.0 as well as a Broad Band does. It also does it as accurately as the Broad Band does as they are being used today by the aftermarket gauges that are being used.

In your stated example using you TS Broad Band unit your data is no better than and possibly worse than what you can get today from the Narrow Bands that are already there and as a matter of fact your TS unit is giving you an average reading of what the engine did over some 14 engine fire cycles at best.  When the Narrow Bands can and do give you a reading from each and every engine cycle.

ok, maybe I misunderstood this:

I am unaware of anyone that is supplying a system today that really measures narrow bands at heavy loads for tuning at this time, the ones I have tested all extend or project the data as the HD ECM has all or part of the correction terms turned off under those conditions, so I cannot see how you can make the claims your trying to make.

Steve, the above was your own words, not mine....but in the above, we agree.   I do not know of a system on the market today that really measure narrow bands at heavy load and provide data for tuning.  I really don't care about theoretical can do's, I want practical and available.  With that said, I will use a product that is on the market and is accurate enough for the allowable deviation.   

[mayor]

Be careful in assuming that these aftermarket devices using the Bosch LSU4.x sensor are really going to correct as you are lead to believe they are.

what's your take on NGK NTK UEGO sensors?  I'm assuming these do not have the same issues as the Bosch sensors? 

[Steve Cole]

You have been able to measure the Narrow Band sensors at WOT with DataMaster for over 7 years, it's included with the product! There is no one using it at this time for populating the near WOT VE table tuning for you, but that sure doesn't stop you from doing it any more than using Broad Bands to do it. So all it takes is the same amount of effort you put into Broad Bands to do it with DataMaster. So you have practical and available in your hands today.

The NTK sensors are good but it all depends on the electronics they are hooked too. Without knowing that who knows.

[mayor]

You have been able to measure the Narrow Band sensors at WOT with DataMaster for over 7 years, it's included with the product! There is no one using it at this time for populating the near WOT VE table tuning for you, but that sure doesn't stop you from doing it any more than using Broad Bands to do it. So all it takes is the same amount of effort you put into Broad Bands to do it with DataMaster. So you have practical and available in your hands today.

if what you are referring to is sensor voltage, I disagree that it can be done with the same amount of effort.  I would give you possible, but I would not practical.  I don't doubt that some one who puts their mind to it could make it work, but I'm pretty that that same person could have those same cells dialed in with a broad band unit in far less time...with far less miles at heavy load. 

The NTK sensors are good but it all depends on the electronics they are hooked too. Without knowing that who knows.

I bought a couple NGK's Powerdex afr monitors, and the one's I got had the NTK sensors as opposed to the Bosch sensors.  The Powerdex is made by ECM, for NGK.   I've read quite a few comments from Greg Banish on that unit, and he's claiming that they are quite accurate from .7-1 lambda. 

[Steve Cole]

If those units are now coming with the NTK sensor and it's used properly they should be much better than the Broad Band units out there. In the past the NGK units have all used the Bosch sensor with the same downfall as all the others. Greg is a personal friend of mine so I will give him a call and see what he's looked at on the NGK unit.

[mayor]

that would be cool.   

[old_dirt]

Mike, you know that I have been using the powerdex stuff for awhile, and while they do NOT use the same NGK stuff and the lambda pro from ECM, I still can't help but think.... since it IS NGK, and it is ECM...  should be better than the bosch stuff until someone maybe gets 4.9s going.  I have patiently waited for someone like DTT to use a whole new controller and use 4.9s.  4.9s are what OEMs basically use now a days, 4.2s are passe.

[mayor]

I didn't realize that that was the NTK system you had.  I remember you talking about the sensors, but I don't know if you ever told me what the controller was.  How did you get past the scaling issue?  I talked to Sandro a couple of weeks ago and he said he will add that to the list of inputs to the Centurion.  I still haven't spent the money on the TR system yet, but it's on my list of things to do in Cinci.

I really don't understand why DTT doesn't upgrade their system.  I think that the whole system could be improved, not just the sensors.  

[whittlebeast]

This place would make a woodpecker's  head hurt.   It's a two cylinder, wobble fire tractor motor.

.3 sec response time has nothing to do with sample rate,  It has everything to do with matching up the data packets and filtering data.

Andy