Eagle7
New member
Thank you master. I walked away from my computer troubled by my "is it binding?" comment, and came back to write essentially what Greg wrote. Wouldn't have done it nearly as eloquently, though.
It does something different (which is why you want to use it). This is precisely why it is not equivalent.
Andy Bettencourt
Super Moderator
That IS the definition in the GCR my friend. Page 111.
Andy Bettencourt
Super Moderator
Quoted again for a very simple truth.
chuck baader
New member
Ok, we'll assume
. Chuckl
. Chuckl
Eagle7
New member
Eagle7
New member
Sorry forHmmm. Serves me right for using an old GCR.
Thanks for the correction.
but now I really don't understand this rule.Other existing sensors, excluding the stock air metering device, may be substituted for equivalent units.
Equivalent - [FONT=Univers,Univers][FONT=Univers,Univers]The same form, fit, function, and dimensions. [/FONT][/FONT]
[FONT=Univers,Univers][FONT=Univers,Univers][/FONT][/FONT]
[FONT=Univers,Univers][FONT=Univers,Univers]So I can replace a sensor, say a coolant temp sensor, with an alternate, but it must be the same form, fit and dimensions as the OEM sensor? So it must have the same shape, it must screw into the same hole, it must use the same connector, it must have exactly the same dimensions. I cannot belive that was the intent of the rule. Especially since "equivalent" wasn't in the glossary when the rule was written. I think the glossary entry added this year totally changes this rule.
[/FONT][/FONT]
Andy Bettencourt
Super Moderator
I think you are reading too much into it. If you want to replace your OEM sensor, it should be the same. If you want to ADD one to run your allowed gauge, it can be what runs the guage because you damn well can add that gauge and that is what makes it work. Of course it can not also do something that is prohibited as we know.
Now WRT sensors that provide input to the ECU, there is a specific rule. What is stock (or equivilent) or what is listed as legal to be added. Right?
Now WRT sensors that provide input to the ECU, there is a specific rule. What is stock (or equivilent) or what is listed as legal to be added. Right?
...and thus makes it wholly redundant to GCR/ITCS 9.1.3.C paragraph three, which WAS in the rules prior to the ECU change, as I recall...
Which makes one wonder: just exactly what was the point of GCR/ITCS 9.1.3.D.1.a.6 last sentence, if not to do exactly as Marty implies...?
Eagle7
New member
I quoted the rule that explicitly listed which sensors ("other existing") that could be substituted for the stock sensors. See tGA's comments.
Ultimately (ITAC guys take note) this conversation reinforces my opinion that we shouldn't even have acted on this item. It doesn't ask for a rule change: It asks for an interpretation, a function that we aren't empowered to exercise.
Greg said it: The ITAC isn't the source of a resolution to this kind of question and we did *not* contribute to clarity or serve the membership well by getting involved. In fact, we complicated the conversation with the reply in Fastrack.
K
Greg said it: The ITAC isn't the source of a resolution to this kind of question and we did *not* contribute to clarity or serve the membership well by getting involved. In fact, we complicated the conversation with the reply in Fastrack.
K
Andy Bettencourt
Super Moderator
Except open conversation like this help everyone understand the multitude of thoughts and issues on this item and potentially others that may use 'equivalent' wording. 
JoshS
New member
Chuck,
I'm definitely not an expert but I don't think your characterization of the difference between NB and WB is correct, or at least, it's incomplete. The O2 sensor doesn't know whether or not you are at WOT, of course.
A NB is essentially a binary signal. Either your mixture is stoichometric or it isn't. But a WB will give you an idea of how far off you are. The only thing that's pertinent to WOT is that often you don't WANT to be at stoichometric at WOT, which is why most systems go open-loop at WOT -- the NB O2 sensor can't help in that situation.
A decent analogy would be this -- imagine there was no allowance for a throttle position sensor in the rules. Your car comes with a kick-down switch that allows the car to know when you are at full throttle, but it doesn't know any more details than that. Would you be able to use the "equivalence" allowance to replace the kick-down switch with a throttle position sensor?
Last edited:
planet6racing
New member
Sorry for
Other existing sensors, excluding the stock air metering device, may be substituted for equivalent units.
Equivalent - [FONT=Univers,Univers][FONT=Univers,Univers]The same form, fit, function, and dimensions. [/FONT][/FONT]
[FONT=Univers,Univers][FONT=Univers,Univers]So I can replace a sensor, say a coolant temp sensor, with an alternate, but it must be the same form, fit and dimensions as the OEM sensor? So it must have the same shape, it must screw into the same hole, it must use the same connector, it must have exactly the same dimensions. I cannot belive that was the intent of the rule. Especially since "equivalent" wasn't in the glossary when the rule was written. I think the glossary entry added this year totally changes this rule.[/FONT]
[/FONT]
Marty:
That rule was written so that people could buy parts from Autozone et al. instead of needing to go get OEM parts from the dealer. Example: On the Saturn, the coolant temperature sensor is known to go wonky and mess with the ECU. Going by the original set of rules (before this one was added), I needed to go to Saturn and purchase the sensor, costing me about $40. Now, with the new rule, I can get the sensor with the same Fit, Function, and Dimensions, but without the OEM part number and made of plastic instead of brass for ~$15. Another example that was used on this board was brake rotors - theoretically, before this rule, these needed to be purchased at the dealer with the OEM part numbers.
So, yes, the replacement part should fit in the same location and serve the same purpose as the part it is replacing.
chuck baader
New member
Josh, I agree. I certainly did not do enough research before requesting a clarification. No one as yet has answered the basic question...what is the difference? (that the CRB hangs their collective hat on.)
As for the TPS, most cars of my era use just that. So we allow a linear pot to replace a switch but not the O2? Maybe we should outlaw all electronics and go back to multiple carbs..just think of the money we could save!! Chuck
As for the TPS, most cars of my era use just that. So we allow a linear pot to replace a switch but not the O2? Maybe we should outlaw all electronics and go back to multiple carbs..just think of the money we could save!! Chuck
RexRacer19
New member
Maybe this would be useful for the discussion. Certainly not the gospel, but a good explanation of the two sensors being discussed.
http://en.wikipedia.org/wiki/Oxygen_sensor
http://en.wikipedia.org/wiki/Oxygen_sensor
Boy, are we seriously drifting off the range here...
Bill (Planet 6), I accept your thesis as reasonable, but I think it's flawed. As I noted above, if that was the intent of the rule then there would be no need for the notation within the ECU rules, as it's already specified in the opening paragraphs. This means one of three things: either the rule was poorly written (NO WAY!!!!), it's actually redundant to the opening paragraphs, or there were other reasons behind that rule.
I'm taking Door Three, Alex.
Andy comes out and states, in effect, the sensor have to be the same as stock. Josh states it's a matter of range (binary versus analog). Others above imply the sensor has to be the same physically. But let's take this logically; are you telling me that if you're using a MoTec or a HalTech, or a MegaSquirt, or whatever, that the sensors you're using to feed that beast - with the exception of TPS and MAP - must all be stock, using the stock voltages and stock ranges? So, you really believe that the intent of the rule as stated is that if you install a Haltech ECU into your car, you can ONLY use the stock sensors and add only a TPS and MAP? Be careful of your answers here.
Door Three basically says that the interpretation of the rule is to keep you from adding additional sensors to your car that, with the exception of TPS and MAP, were not original equipment. This would, for example, preclude you from adding a crank angle sensor. It does not, however, preclude you from replacing existing sensors (i.e., water temp, oil pressure, IAT, etc) with sensors that have the same function (e.g., measures water temp, measures oil pressure, measures intake air temperature) but may be reasonably different in terms of physical characteristics and characteristics of sensing. Thus, one can replace the OE water temp sensor with a Bosch sensor that measures within a different voltage range and/or possibly a wider range and/or tighter tolerances.
Thus, we go full-circle back to the wideband sensor issue. Given the allowance in the ECU rule for replacing a sensor with one that has "equivalency", and given that an O2 sensor's function is to sense the level of O2 in the system, and given that per Door Three we are OK with folks replacing other sensors with equivalent sensors but may have different ranges and/or tolerances, it is not a very large leap of faith to state that a wideband O2 sensor is an equivalent sensor in that it measures relative oxygen level yet it measures over a wider range with tighter tolerances.
To take a position contrary to this means that NO other sensors may be replaced with any parts other than what is described in the opening ITCS paragraphs (what Josh is stating) and thus:
- GCR/ITCS 9.1.3.D.1.a.6 last sentence is wholly redundant and confusing, thus we now expect the ITAC to immediately address this discrepancy by recommending this sentence to be stricken from the regulations entirely, and
- Anyone that is using sensors that do not meet the OE specifications of the parts as delivered with their vehicles is operating contrary to the rules and should immediately discontinue using them and re-adjust their Haltechs/MoTEC/Megasquirts to use OE sensors only. Furthermore, anyone whose car came stock with a MAP and TPS may only use those stock items; you may not replace them with ones more-compatible with your ECU (no allowance in the rule to replace, only "add").
Fun, huh?
Just to toss in more confusion, for those of you saying you can't add sensors other than a TPS and/or MAP, are you stating that adding a baro read solenoid or a temperature sensor - or any other kind of atmospheric measurement device - directly on the board of the ECU itself is illegal (and was thus illegal prior to the ECU rule being opened up)? If you say it's Ok to do so ONLY if it's on the board, why can't you do it as part of the "virtual ECU" (tm, Bill Miller) given that there's no physical or geographical limitations to what an ECU can be?
I know what you think the rules say. I know what you think the rules mean. But that ain't what they are...and if you think this is the only rule in the ITCS with this kind of clever ambiguity, well, you ain't readin'...
GA
Bill (Planet 6), I accept your thesis as reasonable, but I think it's flawed. As I noted above, if that was the intent of the rule then there would be no need for the notation within the ECU rules, as it's already specified in the opening paragraphs. This means one of three things: either the rule was poorly written (NO WAY!!!!), it's actually redundant to the opening paragraphs, or there were other reasons behind that rule.
I'm taking Door Three, Alex.
Andy comes out and states, in effect, the sensor have to be the same as stock. Josh states it's a matter of range (binary versus analog). Others above imply the sensor has to be the same physically. But let's take this logically; are you telling me that if you're using a MoTec or a HalTech, or a MegaSquirt, or whatever, that the sensors you're using to feed that beast - with the exception of TPS and MAP - must all be stock, using the stock voltages and stock ranges? So, you really believe that the intent of the rule as stated is that if you install a Haltech ECU into your car, you can ONLY use the stock sensors and add only a TPS and MAP? Be careful of your answers here.
Door Three basically says that the interpretation of the rule is to keep you from adding additional sensors to your car that, with the exception of TPS and MAP, were not original equipment. This would, for example, preclude you from adding a crank angle sensor. It does not, however, preclude you from replacing existing sensors (i.e., water temp, oil pressure, IAT, etc) with sensors that have the same function (e.g., measures water temp, measures oil pressure, measures intake air temperature) but may be reasonably different in terms of physical characteristics and characteristics of sensing. Thus, one can replace the OE water temp sensor with a Bosch sensor that measures within a different voltage range and/or possibly a wider range and/or tighter tolerances.
Thus, we go full-circle back to the wideband sensor issue. Given the allowance in the ECU rule for replacing a sensor with one that has "equivalency", and given that an O2 sensor's function is to sense the level of O2 in the system, and given that per Door Three we are OK with folks replacing other sensors with equivalent sensors but may have different ranges and/or tolerances, it is not a very large leap of faith to state that a wideband O2 sensor is an equivalent sensor in that it measures relative oxygen level yet it measures over a wider range with tighter tolerances.
To take a position contrary to this means that NO other sensors may be replaced with any parts other than what is described in the opening ITCS paragraphs (what Josh is stating) and thus:
- GCR/ITCS 9.1.3.D.1.a.6 last sentence is wholly redundant and confusing, thus we now expect the ITAC to immediately address this discrepancy by recommending this sentence to be stricken from the regulations entirely, and
- Anyone that is using sensors that do not meet the OE specifications of the parts as delivered with their vehicles is operating contrary to the rules and should immediately discontinue using them and re-adjust their Haltechs/MoTEC/Megasquirts to use OE sensors only. Furthermore, anyone whose car came stock with a MAP and TPS may only use those stock items; you may not replace them with ones more-compatible with your ECU (no allowance in the rule to replace, only "add").
Fun, huh?
Just to toss in more confusion, for those of you saying you can't add sensors other than a TPS and/or MAP, are you stating that adding a baro read solenoid or a temperature sensor - or any other kind of atmospheric measurement device - directly on the board of the ECU itself is illegal (and was thus illegal prior to the ECU rule being opened up)? If you say it's Ok to do so ONLY if it's on the board, why can't you do it as part of the "virtual ECU" (tm, Bill Miller) given that there's no physical or geographical limitations to what an ECU can be?
I know what you think the rules say. I know what you think the rules mean. But that ain't what they are...and if you think this is the only rule in the ITCS with this kind of clever ambiguity, well, you ain't readin'...
GA
Last edited:
shwah
New member
Wow. Has the racing season ended early this year?
Agreed that there is some grey here, that Greg is theorizing about exploiting.
I think he would end up on the wrong side of a protest, but we just don't know until that were to happen.
As far as I am concerned do eet. You won't make one more measurable horsepower, and will put your engine at more risk than running off open loop maps developed with appropriate dyno tuning.
My approach is like the others. Have one. Log it. Don't run closed loop on the ecu on track. Maybe run closed loop on the dyno during tuning to see what it 'wants'.
Agreed that there is some grey here, that Greg is theorizing about exploiting.
I think he would end up on the wrong side of a protest, but we just don't know until that were to happen.
As far as I am concerned do eet. You won't make one more measurable horsepower, and will put your engine at more risk than running off open loop maps developed with appropriate dyno tuning.
My approach is like the others. Have one. Log it. Don't run closed loop on the ecu on track. Maybe run closed loop on the dyno during tuning to see what it 'wants'.