Andy Bettencourt
Super Moderator
True...true. Not an allowable 'addition'.
True...true. Not an allowable 'addition'.
Eagle7
New member
Yes on a Megasquirt. The Gego value in the log is the % multiplier of fuel due to O2 sensor input. 100% means no effect. It can also be determined without a log by checking the configuration (connect a computer and check a setting). However all of that assumes standard ECU firmware that doesn't "lie".
I personally would be happy to disconnect my WBO2 if a competitor expressed a concern.
I think that this was greg's only point and I agree with it being hard to police. I do agree it is not technically legal to use it for the ecu, just hard to control what someone does with the info.
Bill Miller
New member
Exactly
Wires in the engine harness aren't exactly 'free'. You can modify them or replace them Doesn't say you can add additional ones. And please don't say that changing what they're connected to falls under 'modification'.
Do you consider the ECU to be part of the engine harness? I don't.
And while I appreciate what you're saying, I don't know of anything in the IT PP&I that allows things specifically because it 'makes something easier'.
chuck baader
New member
A question for the rules nerds. First, a NB O2 sensor sends a signal to the ECU, upon which adjustments are made. How in the hell does that differ from a WB O2 sensor? Functionally they both do the same thing. Since ECUs are free, and all ECUs manufactured since there has been an O2 sensor use them to adjust mixture, DUH!!!!! Chuck
And (thanks again, Bill) my Schrick aftermarket cam "does the same thing" as the stock one I took out. It just does it better.
Not really. From the GCR:Equivalent - The same form, fit, function, and dimensions.
I can't simply pull out the stock NB O2 in my Golf and plug in a WB. I need a controller, that generates the signal that makes the new one - with more wires - work. That's NOT the same in "function," even if it does screw into the same bung.
K
I don't see this as that hard to police. If the wires go to the ECU it is not legal, period (even in practice sessions, test day ok though). I don't care what you say you're doing with the data, or any log files you produce that show it wasn't used for tuning. I could generate similar log files in my car that say your car was using the sensor. Clearly those would be fabricated, but what proves yours aren't also?
Hmm, maybe if I stick a nitrous bottle in an extra temperature gauge...
Hmm, maybe if I stick a nitrous bottle in an extra temperature gauge...
Without a clarification that an equivalent sensor has to function in a 100% factory electrical specification, and since connectors can be modified or replaced; then it really is not a hard stretch to get to changing sensors out. That is what this is about.
No. But I am trying to understand that if I put another ECU in that will require different ECU connections. Do I have to use the existing ecu connector (aka an ECU adapter), or can the cutters come out and just remove that connector and use the new one? My read is the connector can be replaced with another since it is serving no additional function than the previous one. Also since it is still connecting up the the factory sensors (now that that is clear), I will be ok.
Now how would you be able to connect additional power and ground, or communications for data logging and gauges to the ECU without adding additional wire? And would I be able to omit emissions equipment wiring and connectors in the new system? Or can I only modify it to a really short connector?
It may need to fall under the, it will keep the cost down, since the ECU (especially standalone) can do the translation of the sensor to the datalogger/ gauge vs. an additional standalone box.
This is the reason I and others have data loggers hooked to the ECUs. Why should we duplicate sensors, especially slow moving ones like temperatures, when the ECU is already doing it. Now in my case, I did add an oil pressure sensor for datalogging and gauges, since the factory is just a trigger switch. Now I would have liked to change that switch complete out to the sensor in the "new" ECU. Internally it would have become the electric switch it replaced, but after this discussion it does not seem to be legal.
Also why did they then allow for TPS and MAP sensors? That did make it easier (and potentially less $$) to switch from MAF to a speed density. Though those Miata's still have to suck their air through the factory MAF sensor.
Again I am not looking to make a big deal out of this I just want to know what can be done so I do it only once.
ummm nothing says that the data logger and the ecu must be seperate components (both are allowed) and most aftermarket ecus have some data logging ability. I give up you can think whatever you want, someone will do this and get away with it, it won't be me.
Ron Earp
Administrator
So it looks like the popular opinion is that you can't use your wide band to allow the ECU to adjust fuel metering during the race.
Questions:
- During a race what if you, the driver, observe your dash mounted wide band O2 sensor display and reach over and turn a potentiometer (or whatever actuator you like) that adjusts your air fuel ratio? Legal?
- During a race what if you, the driver, reach over and turn a potentiometer (or whatever actuator you like) that adjusts your air fuel ratio (no wide band O2 sensor involved)? Legal?
Last edited:
Gary L
New member
Both (1). and (2.) seem legal to me. In my particular case, an EGT guage is my budget-racer version of the WB O2 sensor. The potentiometer in this case is a driver-adjustable fuel pressure regulator. Observe the EGT guage, adjust the FPR... my stock 1971 briefcase-sized "ECU" never knows the difference.
And oh yeah, like Charles B., I'm still using the stopwatch taped to the steering wheel. I'm thinking some of you guys are taking this shit WAY too seriously. Yes, I know... someone's gotta do it.
chuck baader
New member
Here is the original request based on a question response by Chris Albin:
"Gentlemen: The following is a decision by the CRB concerning wide band O2 sensors.
" Kevin,
The Committee felt that the wide band o2 sensor would only be legal if used to feed a gauge if it were hooked to the ECU it would not be legal. I suggest that he write a letter asking for that change and it may be considered. Last night they did not want to change the language to allow it.
Thanks,
Chris Albin CRB"
I am requesting a re-evaluation of this position for the following reasons:
1. GCR page 333, paragraph 6: "Other existing sensors, excluding the stock air metering device, may be substituted for equivalent units."
Comment: I maintain that a wide band O2 is an equivalent substitution for a narrow band since both units supply the air fuel ratio to the engine control unit (ECU). Both a narrow band and wide band O2 sensors allow the ECU to adjust the fuel air ratio in real time so functionally they are the same. The difference lies in wide open throtle (WOT). The narrow band unit will not adjust fuel air at WOT whereas the wide band will. The difference in functionality is at one throttle setting. See Item #2.
2. It is my opinion that with the allowance of the MAP and TPS sensors, and the substitution of other sensors, the intent of the rules change was to allow after market ECUs which generally (but not necessarily) run closed loop on the wide band sensor.
3. Actually, I feel the wording of the referenced paragraph is adequate as written as "substitution for equivalent units" should allow the wide band unit.
Thanks for your time and interest...Chuck Baader 265512 "
I will reiterate my premise: It does the same thing "functionally"...it has to be legal:026:Chuck
"Gentlemen: The following is a decision by the CRB concerning wide band O2 sensors.
" Kevin,
The Committee felt that the wide band o2 sensor would only be legal if used to feed a gauge if it were hooked to the ECU it would not be legal. I suggest that he write a letter asking for that change and it may be considered. Last night they did not want to change the language to allow it.
Thanks,
Chris Albin CRB"
I am requesting a re-evaluation of this position for the following reasons:
1. GCR page 333, paragraph 6: "Other existing sensors, excluding the stock air metering device, may be substituted for equivalent units."
Comment: I maintain that a wide band O2 is an equivalent substitution for a narrow band since both units supply the air fuel ratio to the engine control unit (ECU). Both a narrow band and wide band O2 sensors allow the ECU to adjust the fuel air ratio in real time so functionally they are the same. The difference lies in wide open throtle (WOT). The narrow band unit will not adjust fuel air at WOT whereas the wide band will. The difference in functionality is at one throttle setting. See Item #2.
2. It is my opinion that with the allowance of the MAP and TPS sensors, and the substitution of other sensors, the intent of the rules change was to allow after market ECUs which generally (but not necessarily) run closed loop on the wide band sensor.
3. Actually, I feel the wording of the referenced paragraph is adequate as written as "substitution for equivalent units" should allow the wide band unit.
Thanks for your time and interest...Chuck Baader 265512 "
I will reiterate my premise: It does the same thing "functionally"...it has to be legal:026:Chuck
Andy Bettencourt
Super Moderator
So Chuck - please help us. Define 'functionally'. How about Kirk's camshaft analogy?
'The same in form, fit and function.' SAME....
JeffYoung
New member
But we are not allowed to "substitute equivalent" camshafts are we?
If we use an aftermarket piece, it is to be identical, not equivalent.
I do think we need definition here. As some of you guys know, I asked around about moving the distributor based cam/crank position sensor in my car to the crank pulley on the theory that it was an equivalent sensor. Basically the same as teh letter we got last week.
The consensus was I was being aggressive but arguably legal. We've now decided it's not (and I had to use the distributor anyway), and that's fine -- but I don't think the "equivalent sensor" rule is as clear as some folks on the CRB seem to think.
Does everyone have their stock air temp and water temp sensors in the same place or did you move them for convenience (i.e. to add a gauge)? If you have a TPS stock, are you using it or one that reads more accurately/is more durable?
And now the kicker -- how about the cam position sensor on the 99 Miata that fails all the time? I'm aware of the fix, am personally fine with it, but don't think it is legal under this strict definition of "equivalent" sensor.
If we use an aftermarket piece, it is to be identical, not equivalent.
I do think we need definition here. As some of you guys know, I asked around about moving the distributor based cam/crank position sensor in my car to the crank pulley on the theory that it was an equivalent sensor. Basically the same as teh letter we got last week.
The consensus was I was being aggressive but arguably legal. We've now decided it's not (and I had to use the distributor anyway), and that's fine -- but I don't think the "equivalent sensor" rule is as clear as some folks on the CRB seem to think.
Does everyone have their stock air temp and water temp sensors in the same place or did you move them for convenience (i.e. to add a gauge)? If you have a TPS stock, are you using it or one that reads more accurately/is more durable?
And now the kicker -- how about the cam position sensor on the 99 Miata that fails all the time? I'm aware of the fix, am personally fine with it, but don't think it is legal under this strict definition of "equivalent" sensor.
Eagle7
New member
Other existing sensors, excluding the stock air metering device, may be substituted for equivalent units.
Andy, it doesn't say "same in form, fit and function" - it says "equivalent". I can't find a definition of that word in the GCR, but it is used in a variety of ways. One use says a brake caliper is equivalent to a wheel cylinder.
I'm convinced in my mind that the allowance to substitute equivalent sensors had the purpose of accomodating the ease of application of the aftermarket ECU - for example, a different resistance curve on a termperature sensor. I do not think "same in form, fit" applies to this purpose.
All that being said, I think the important issue is "function". Reasonable people can argue both sides of whether WB performs the same function as NB. However if the Fastrack response is binding (is it?), what reasonable people think doesn't matter, because "on high" has spoken.
However, the context of the letter is to use the WB signal to control fuel mixture during race conditions. The "not equivalent" response indicates a negative answer to that specific question. I don't believe it provides any guidance with regard to the logging questions raised here.
One writes an email to the CRB to request a rule change. Chuck (apparently) did so, and his rule change request was denied. What the "opinion" of the CRB (or any one particular CRB member) is vis-a-vis the rule application/interpretation is wholly irrelevant.
If Chuck's intent was to get a clarification of an existing rule or a request to interpret a rule a specific way, then Chuck should have used the GCR 8.1.4 process. He did not.
Ergo, nothing (zero, zilch, nada) has changed vis-a-vis the rules regarding wideband O2 sensors, regardless of what one may have read in this month's Fastrack.
GA
If Chuck's intent was to get a clarification of an existing rule or a request to interpret a rule a specific way, then Chuck should have used the GCR 8.1.4 process. He did not.
Ergo, nothing (zero, zilch, nada) has changed vis-a-vis the rules regarding wideband O2 sensors, regardless of what one may have read in this month's Fastrack.
GA
chuck baader
New member
Andy, Kirk's analogy of the cam won't fly since the paragraph we are discussing is for the "engine management computer".
ITCS1.A 6. The engine management computer may be altered or
replaced. A throttle position sensor and its wiring may
be added or replaced. A MAP sensor and its wiring may
be added. Other existing sensors, excluding the stock air
metering device, may be substituted for equivalent units.
1.A.77. Wires and connectors in the engine wiring harness may be
modified or replaced.
Note: the GCR wording is "equivalent", which is defined in the GCR Glossary as " Equivalent: The same form, fit, function, and dimensions." They both look the same, fit the same place, send a voltage signal to the ECU, and use the same wrench. Why aren't they "equivalent"?
I don't know about your wiring and ECU, but the engine harness on my car contains the connection for the O2 sensor. Therefore, "Wires and connectors in the engine wiring harness may be modified or replaced" so it seems to me the wiring is, for all intents and purposes, free.
Therefore, I have a legal ECU, MAP sensor, TPS sensor, and temp sensor...sensors allowed per the quoted paragraph, but the substitution of the O2 sensor is not legal? Someone on the CRB please explain the logic behind the ruling. Chuck
ITCS1.A 6. The engine management computer may be altered or
replaced. A throttle position sensor and its wiring may
be added or replaced. A MAP sensor and its wiring may
be added. Other existing sensors, excluding the stock air
metering device, may be substituted for equivalent units.
1.A.77. Wires and connectors in the engine wiring harness may be
modified or replaced.
Note: the GCR wording is "equivalent", which is defined in the GCR Glossary as " Equivalent: The same form, fit, function, and dimensions." They both look the same, fit the same place, send a voltage signal to the ECU, and use the same wrench. Why aren't they "equivalent"?
I don't know about your wiring and ECU, but the engine harness on my car contains the connection for the O2 sensor. Therefore, "Wires and connectors in the engine wiring harness may be modified or replaced" so it seems to me the wiring is, for all intents and purposes, free.
Therefore, I have a legal ECU, MAP sensor, TPS sensor, and temp sensor...sensors allowed per the quoted paragraph, but the substitution of the O2 sensor is not legal? Someone on the CRB please explain the logic behind the ruling. Chuck
chuck baader
New member
Greg, you are right...I should have done that in the first place. I will make it so. Chuck
JeffYoung
New member
Chuck, I think Greg's point is maybe you don't want to do anything else at this point.....
Also, speaking totally for myslef, what I heard on our call the other night was that a Wideband 02 does not perform the same function as a narrow so it is not the equivalent. That was the rational used to craft the response we recommended.
Also, speaking totally for myslef, what I heard on our call the other night was that a Wideband 02 does not perform the same function as a narrow so it is not the equivalent. That was the rational used to craft the response we recommended.