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Discussion Starter · #1 ·
Is there a company who makes an engine management system that utlizes a wideband and that can adjust A/F on the fly based on the readings it receives from the wideband?
So...once it's installed, the engine management system adjusts A/F +/- the needed %?

Or...anything similar?
 

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The TEC3 with wideband input will make "minor adjustments." I'm not exactly sure what that means, but that's all I found out from PFS.

Now give me some dots, beatch!
 

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Discussion Starter · #4 ·
Alrighty....Jeff...you only received ONE dot because you supplied a 1/2 answer :D

We have 2 votes for the TEC3.

I remember someone mentioning this as well, but I thought it only data logged, not adjusted on the fly. Anyone else know for sure?
 

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it's called closed loop tuning, and most engine managements will do it (motec, haltech, tec3) if you have a wideband installed.

-Chris
 

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Discussion Starter · #7 ·
doublins said:
it's called closed loop tuning, and most engine managements will do it (motec, haltech, tec3) if you have a wideband installed.

-Chris
R-e-e-e-a-l-y?

No sheit. I guess that that is what "dedicated closed loop idle control &
dedicated closed loop O2 correction" means?
 

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I'm not sure how much adjusting it does though. I was hitting 12.5 AFR under boost, but if the wideband was really being considered it should have adjusted the AFR to 12.0. I'm not an expert on the TEC3, but I thought it would correct something like that.
 

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ISJeff said:
I'm not sure how much adjusting it does though. I was hitting 12.5 AFR under boost, but if the wideband was really being considered it should have adjusted the AFR to 12.0. I'm not an expert on the TEC3, but I thought it would correct something like that.
sounds like it does not correct at all under open-loop conditions. A lot of ems' don't. In fact the only one I know of that DOES correct open-loop is the motec m800, but at the pricetag of a cool 8 Gs :-?
 

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Hmm, I might have mis-understood, but I was told by an expert source that on Haltec E6K the a/f ratio is automatically adjusted for difference (changes) in temperature (hot weather-summer and cold weather (winter). That we don't need to redyno and tune just soley for different seasonal temp. changes....
 

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Discussion Starter · #11 ·
It looks like this is comming down to "open loop" vs "closed loop". Can someone explain to be what the difference is? And of course...since I have the SRT kit...which mine is (my guess would be open).

Thanks :D
 

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redline814 said:
It looks like this is comming down to "open loop" vs "closed loop". Can someone explain to be what the difference is? And of course...since I have the SRT kit...which mine is (my guess would be open).

Thanks :D
Closed loop is when the ECU makes its own adjustments to fuel and timing based on what sensor readings are. Open loop is when the ECU makes fuel and timing adjustments base on preprogrammed values.
 

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Most ECUs run closed loop up to a certain load point then switches to open loop above that. The hype now is getting closed loop operation aka autotuning all the way up to WOT with accuracy and consistency.
 

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Discussion Starter · #14 ·
trekster said:
Most ECUs run closed loop up to a certain load point then switches to open loop above that. The hype now is getting closed loop operation aka autotuning all the way up to WOT with accuracy and consistency.
"autotunig" - I like that. However, I bet it will cost $$$$$.
 

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redline814 said:
trekster said:
Most ECUs run closed loop up to a certain load point then switches to open loop above that. The hype now is getting closed loop operation aka autotuning all the way up to WOT with accuracy and consistency.
"autotunig" - I like that. However, I bet it will cost $$$$$.
The TEC3 has this capability as well now. They just released a firmware upgrade which I installed a few weeks ago. Once you interface the wideband unit to it, you can go to the EGO table and plug the the desired AFR at specific map and rpm points. You can also plug in the lower and upper limits of AFR (voltage) so that if the TEC3 reads anything outside the limits it will fall back to your base map settings. Sounds all good but I have yet to try it. I have been told by others that it may not work reliably at WOT but it does work much better than a factory narrow band because it will autotune at much higher loads. I am hoping to get better mileage out of this. The other nice feature is being able to datalog AFR vs RPM.
 

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Oh, and for any of you interested in a digital wideband unit, check out Innovate Motorsports. I got mine from them and it works awesome and the fact that it's digital should make it work much better when trying to autotune. FYI, many of the early WBs are analog ie FJO which may not process quickly enough for autotuning.
 

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ISJeff said:
I'm not sure how much adjusting it does though. I was hitting 12.5 AFR under boost, but if the wideband was really being considered it should have adjusted the AFR to 12.0. I'm not an expert on the TEC3, but I thought it would correct something like that.
After a lot of help from Chris (trekster) I think I'm starting to understand how this is all working. I looked at my settings for the wideband and it only allows the wideband to make corrections to the AFR up to 135kPa MAP. After that point, the TEC3 relies on the predefined values in the Volumetric Efficiency table. Even when the TEC3 uses the data from the wideband, it has an authority range of 2%. I don't know if that is a 2% change in AFR or 2% change of the values in the VE table. This would explain why my AFR of 12.5 didn't get adjusted to 12.0 at full boost.

All of these paramters can be changed - maximum MAP, RPM at which the wideband data is considered, and authority range. Do I want to be the one to test out how well they work at full boost? No thanks.

On a side note, how do you figure out what boost you're running at by using the MAP? You can't just convert the kPa to psi because that would mean I am running at 27psi daily.
 

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Discussion Starter · #19 ·
Thanks for the follow up. I can understand your unwillingness to play with it under full boost. But, do you know if PFS has completed such testing yet and would be able to send you TEC3 users a new map (or what ever that file would be called)? If so, that's pretty damn cool...
 

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I don't know if they are ready to fully trust the wideband to run the car. When I spoke to Peter about 3 weeks ago, I was asking him about the adjustments and he said "minor adjustments." I think he was talking about the 2%. He said nothing about giving the wideband full control.

Damn, this car stuff is a lot more interesting than creating crappy web pages. Maybe I went into the wrong field.
 
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