AEM fuel/ignition controller
#76
If you keep the AFR at 14.7:1 your going to blow your motor dude. Let me explain what you need to do with the piggyback.
You need to keep your WOT and load AFR at around 11.5 - 11.8 :1. What your going to be doing is called o2 feedback tuning along with fuel tuning. The car needs to THINK its at 14.7:1, not actually be at 14.7:1. You do this by tapping into the narrowband o2 signal. Then while your tuning you must keep your fuel trim within +/- 10 i believe on our ecm(you really want to be around +/- 5). So what you will need to do is use the fuel map AND the o2 map together. You add fuel with the fuel map(or whatever AEM calls it), and then spoof a 14.7 AFR with the o2 map by altering the AFR seen by the o2 sensor so when the added fuel is there, the car only reads 14.7:1. Thats the only way your going to keep from throwing a CEL. Now it would be nice if the piggyback does this on its own, but from what i have seen from the original software i dont believe it did.
You need to keep your WOT and load AFR at around 11.5 - 11.8 :1. What your going to be doing is called o2 feedback tuning along with fuel tuning. The car needs to THINK its at 14.7:1, not actually be at 14.7:1. You do this by tapping into the narrowband o2 signal. Then while your tuning you must keep your fuel trim within +/- 10 i believe on our ecm(you really want to be around +/- 5). So what you will need to do is use the fuel map AND the o2 map together. You add fuel with the fuel map(or whatever AEM calls it), and then spoof a 14.7 AFR with the o2 map by altering the AFR seen by the o2 sensor so when the added fuel is there, the car only reads 14.7:1. Thats the only way your going to keep from throwing a CEL. Now it would be nice if the piggyback does this on its own, but from what i have seen from the original software i dont believe it did.
the way it appears to be done on the AEM forums is that the majority of the tuning is done via o2 feedback and then cleaned up afterwards with the fuel map. guess it doesn't really matter though as long as you get the correct result.
so in reality, you really should only be reading 14.7:1 at idle and/or vacum right? i don't have a wideband so not sure how it all reads under partial throttle and coast down...
#77
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as long as you are increasing air flow into the motor some how, i.e. larger piston bore will draw more air in; upgrading to performance cams; upgrading to a higher flowing intake manifold; upgrade to a performance exhaust header; porting and polishing the head; bore out the throtle body or get a larger throtle body (dont recomend the larger throtle body, dont know if would work, but boring out the stock throtle body will work)
those kinds of things in conjunction w/ the f/ic would work well. the only thing that would make it better would being able to advance the timing but that also would require using premium fuel to prevent early dentination.
those kinds of things in conjunction w/ the f/ic would work well. the only thing that would make it better would being able to advance the timing but that also would require using premium fuel to prevent early dentination.
Are you kidding? lol. You buy a wideband o2 Sensor and it tells you your Air/Fuel Ration(AFR). You use that while your tuning to make sure you keep it correct for the rpm and boost level your at. It depends on how your tuning too. Are you tuning via Speed Density, using Boost vs RPM or are you tuning for Throttle position vs Air flow(i believe Alpha-N). If your asking those questions you should not be considering tuning or putting power mods into your car until you fully understand how an engine works. From hardware to tuning. They have great books out that will get you started in the right direction. Just dont stop reading, and let me tell you it took me 8+hrs a day of reading for about 6 months to get to the point where i feel like i know enough to go through with my build. I am also very technical and learn very quickly on my own so it could vary per person. Before this car i knew as much as you do right now.
what are the names of some of the best books you read? i read a few and want more cant find any that i think are good
#78
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If you keep the AFR at 14.7:1 your going to blow your motor dude. Let me explain what you need to do with the piggyback.
You need to keep your WOT and load AFR at around 11.5 - 11.8 :1. What your going to be doing is called o2 feedback tuning along with fuel tuning. The car needs to THINK its at 14.7:1, not actually be at 14.7:1. You do this by tapping into the narrowband o2 signal. Then while your tuning you must keep your fuel trim within +/- 10 i believe on our ecm(you really want to be around +/- 5). So what you will need to do is use the fuel map AND the o2 map together. You add fuel with the fuel map(or whatever AEM calls it), and then spoof a 14.7 AFR with the o2 map by altering the AFR seen by the o2 sensor so when the added fuel is there, the car only reads 14.7:1. Thats the only way your going to keep from throwing a CEL. Now it would be nice if the piggyback does this on its own, but from what i have seen from the original software i dont believe it did.
You need to keep your WOT and load AFR at around 11.5 - 11.8 :1. What your going to be doing is called o2 feedback tuning along with fuel tuning. The car needs to THINK its at 14.7:1, not actually be at 14.7:1. You do this by tapping into the narrowband o2 signal. Then while your tuning you must keep your fuel trim within +/- 10 i believe on our ecm(you really want to be around +/- 5). So what you will need to do is use the fuel map AND the o2 map together. You add fuel with the fuel map(or whatever AEM calls it), and then spoof a 14.7 AFR with the o2 map by altering the AFR seen by the o2 sensor so when the added fuel is there, the car only reads 14.7:1. Thats the only way your going to keep from throwing a CEL. Now it would be nice if the piggyback does this on its own, but from what i have seen from the original software i dont believe it did.
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the way it appears to be done on the AEM forums is that the majority of the tuning is done via o2 feedback and then cleaned up afterwards with the fuel map. guess it doesn't really matter though as long as you get the correct result.
so in reality, you really should only be reading 14.7:1 at idle and/or vacum right? i don't have a wideband so not sure how it all reads under partial throttle and coast down...
so in reality, you really should only be reading 14.7:1 at idle and/or vacum right? i don't have a wideband so not sure how it all reads under partial throttle and coast down...
o2 feedback is alterning the o2 signal so the car will add or remove fuel. But what you really want to do is make it so the computer thinks its still at 14.7:1 and not at 11.5:1 like you want to be(on an FI car). Your doing this because if the car sees your running too rich, it will pull fuel on its own, which you dont want it to do. And thats where fuel trim comes into play. If you alter the cars fuel trim too much, it will throw a CEL and i believe go into limp mode.
o3nisoaso3, i just searched on the forums and on google for each part of the car. Once i grasped the functions of each part of the car, i went on to turbo systems, and read about each part of that. Take it one step at a time. Your curiosity(sp?) will lead the way, or at least mine did. Try this: every time you read a post about something your unsure of, go to google and search it. Find out as much about that topic as you can. Then come back to the forums and do it all over again.
#80
A good site for boosted early 1990's 2.0L 16V GM engines is www.max-boost.co.uk
#81
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so a clamped signal meaning it tricks the ECM for a certain AFR?? bascially locked on to a certain number so that the ecm believes its that certain number.. sorry confused a tad and confusing myself lol..
#82
those are what i got now
i have cams and full exhaust along with an intake soon, thats what i am tuning for. what kinds of power would i be looking at?
what are the names of some of the best books you read? i read a few and want more cant find any that i think are good
i have cams and full exhaust along with an intake soon, thats what i am tuning for. what kinds of power would i be looking at?
what are the names of some of the best books you read? i read a few and want more cant find any that i think are good
http://www.amazon.com/Modify-Managem...048231-2957245
i also have this one but it doesn't really address tuning:
http://www.amazon.com/Street-Turboch...pd_sim_b_img_2
but pretty informative...
#83
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BTW, Ionninja those are two of the most informative books out there. The How to Tune and Modify EMS gives a very good explanation on how EMS and all the supporting components work in terms anyone can understand.
#84
with what I have read so far, you can simply alter the voltage being sent to the ECU by the o2 sensor and the ECU will then pull or add fuel (to an extent) to get you to the AFR you are looking for...
so for instance, if you need additional fuel at a certain point on the map (the one I saw was MAP vs voltage)...you decrease the voltage being sent to the ECU so it will think its running lean and add additional fuel. this is the basics of it from what I understand...
you can also adjust fuel trims and clamp the MAF as well...
Not only does it clamp it, it offers a signal "skew" in which you can alter the feedback signal from the o2 to the PCM in order to pull your fuel trims back to near 0.
BTW, Ionninja those are two of the most informative books out there. The How to Tune and Modify EMS gives a very good explanation on how EMS and all the supporting components work in terms anyone can understand.
BTW, Ionninja those are two of the most informative books out there. The How to Tune and Modify EMS gives a very good explanation on how EMS and all the supporting components work in terms anyone can understand.
still have alot more to read though...
Last edited by IonNinja; 02-13-2008 at 11:14 AM. Reason: Automerged Doublepost
#85
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This I don't think can happen. AEM states their software only works with analog MAFs. Someone wrote a write up on intercepting MAF that Zinner and I questioned. Neither the software or hardware appears to have digital MAF capabilities. AEM support has also stated on their forum that they don't support digital MAFs.
Even if they did, you really wouldn't want to mess with it too much with an electronic throttle. If you skew MAF too far from MAP or TPS you'll end up with limp mode quickly.
Even if they did, you really wouldn't want to mess with it too much with an electronic throttle. If you skew MAF too far from MAP or TPS you'll end up with limp mode quickly.
#86
This I don't think can happen. AEM states their software only works with analog MAFs. Someone wrote a write up on intercepting MAF that Zinner and I questioned. Neither the software or hardware appears to have digital MAF capabilities. AEM support has also stated on their forum that they don't support digital MAFs.
Even if they did, you really wouldn't want to mess with it too much with an electronic throttle. If you skew MAF too far from MAP or TPS you'll end up with limp mode quickly.
Even if they did, you really wouldn't want to mess with it too much with an electronic throttle. If you skew MAF too far from MAP or TPS you'll end up with limp mode quickly.
I don't even know the diff between analog and digital MAF so I can't argue that
I do know they support some form of MAF adjustments but I guess if the above is true we can assume its referring to analog MAFs.
that kinda raises a concern though because in the thread I posted in the tuning forum, I remember reading that if I could make adjustments to the MAF when tuning for mild cams then everything would sort of "fall into place." well if I can't tune the MAF then what? stuck with tuning via o2 feedback?
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I don't even know the diff between analog and digital MAF so I can't argue that
I do know they support some form of MAF adjustments but I guess if the above is true we can assume its referring to analog MAFs.
that kinda raises a concern though because in the thread I posted in the tuning forum, I remember reading that if I could make adjustments to the MAF when tuning for mild cams then everything would sort of fall into place. well if I can't tune the MAF then what? stuck with tuning via o2 feedback?
I do know they support some form of MAF adjustments but I guess if the above is true we can assume its referring to analog MAFs.
that kinda raises a concern though because in the thread I posted in the tuning forum, I remember reading that if I could make adjustments to the MAF when tuning for mild cams then everything would sort of fall into place. well if I can't tune the MAF then what? stuck with tuning via o2 feedback?
The signal that each reports to the PCM. Digital ones report back a frequency analog report a voltage 0-5v.
#88
ohhhh okay actually I remember this being mentioned on the AEM forums somewhere...
sort of off topic but why would an MAF clamp be needed anyway, IIRC the Hahn kit on the LSJ does not max out the MAF so why would this be necessary on 2.2 power levels?
MAP clamp I can understand but not MAF...
sort of off topic but why would an MAF clamp be needed anyway, IIRC the Hahn kit on the LSJ does not max out the MAF so why would this be necessary on 2.2 power levels?
MAP clamp I can understand but not MAF...
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ohhhh okay actually I remember this being mentioned on the AEM forums somewhere...
sort of off topic but why would an MAF clamp be needed anyway, IIRC the Hahn kit on the LSJ does not max out the MAF so why would this be necessary on 2.2 power levels?
MAP clamp I can understand but not MAF...
sort of off topic but why would an MAF clamp be needed anyway, IIRC the Hahn kit on the LSJ does not max out the MAF so why would this be necessary on 2.2 power levels?
MAP clamp I can understand but not MAF...
#90
okay so essentially they're just raising the failure point whereas its not something 2.2 guys can do so we essentially would just clamp it before that point.
makes sense i just didn't think it would be necessary...
makes sense i just didn't think it would be necessary...
Last edited by IonNinja; 02-13-2008 at 02:20 PM.
#91
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with the AEM you aren't clamping the o2 signal you are intercepting it...
with what I have read so far, you can simply alter the voltage being sent to the ECU by the o2 sensor and the ECU will then pull or add fuel (to an extent) to get you to the AFR you are looking for...
so for instance, if you need additional fuel at a certain point on the map (the one I saw was MAP vs voltage)...you decrease the voltage being sent to the ECU so it will think its running lean and add additional fuel. this is the basics of it from what I understand...
you can also adjust fuel trims and clamp the MAF as well...
I got it for Christmas
still have alot more to read though...
with what I have read so far, you can simply alter the voltage being sent to the ECU by the o2 sensor and the ECU will then pull or add fuel (to an extent) to get you to the AFR you are looking for...
so for instance, if you need additional fuel at a certain point on the map (the one I saw was MAP vs voltage)...you decrease the voltage being sent to the ECU so it will think its running lean and add additional fuel. this is the basics of it from what I understand...
you can also adjust fuel trims and clamp the MAF as well...
I got it for Christmas
still have alot more to read though...
the AEM install instructions shows a Tap to the o2 and not an interseption of the wires.
#93
Ok, I have a quick question, I know that you have to look at your afr when tuning with the piggyback. if i where to put a afr gauge on my tri pod would that work instead of getting the widebrand?
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no, you need to get a wideband as the wideband is a AFR gauge.. what your thinking of is the narrowband afr gauge which will do nothing for reading AFRs for our cars.. you need a wideband
#95
sorry, just different terminology...i was thinking of an addtional wire tapping into the o2 sensor and intercepting or skewing the signal.
not having the o2 sensor go directly to the AEM and then to the ECU
poor choice of words, my bad.
are you an electrician by chance?
analog > volts
digital > frequency
makes more sense to me this way
Last edited by IonNinja; 02-13-2008 at 07:21 PM. Reason: Automerged Doublepost
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yes I know that
sorry, just different terminology...i was thinking of an addtional wire tapping into the o2 sensor and intercepting or skewing the signal.
not having the o2 sensor go directly to the AEM and then to the ECU
poor choice of words, my bad.
thanks that clears it right up for me
are you an electrician by chance?
analog > volts
digital > frequency
makes more sense to me this way
sorry, just different terminology...i was thinking of an addtional wire tapping into the o2 sensor and intercepting or skewing the signal.
not having the o2 sensor go directly to the AEM and then to the ECU
poor choice of words, my bad.
thanks that clears it right up for me
are you an electrician by chance?
analog > volts
digital > frequency
makes more sense to me this way
Also ion, think of analog as 0 - 255 and digital being 1's and 0's.
Oh Witt, the FIC software has a clamp section that requires you put a max voltage you want the ECM to read from the MAF. So it has to be digital because its 0 - 5. Even in the FIC's help guide it tells you how to clamp it.
Cobalt05, yes you are tapping into the o2 sensor but its still skewing the numbers. It doesnt HAVE to intercept it to do it.
#97
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Nope, I have been into car audio(and the racing scene) since 2k1ish and am going to school to be an A.S.E. Master Tech. Already got done with one of my electrical classes hence me actually being remotely knowledgable about this stuff.
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Also ion, think of analog as 0 - 255 and digital being 1's and 0's.
Oh Witt, the FIC software has a clamp section that requires you put a max voltage you want the ECM to read from the MAF. So it has to be digital because its 0 - 5. Even in the FIC's help guide it tells you how to clamp it.
Cobalt05, yes you are tapping into the o2 sensor but its still skewing the numbers. It doesnt HAVE to intercept it to do it.
Oh Witt, the FIC software has a clamp section that requires you put a max voltage you want the ECM to read from the MAF. So it has to be digital because its 0 - 5. Even in the FIC's help guide it tells you how to clamp it.
Cobalt05, yes you are tapping into the o2 sensor but its still skewing the numbers. It doesnt HAVE to intercept it to do it.
A work around is to build a larger diameter custom intake pipe. More airflow will go by at a lower frequency.
http://forum.aempower.com/forum/inde...c,20963.0.html
http://forum.aempower.com/forum/inde...c,21284.0.html
http://forum.aempower.com/forum/inde...c,20502.0.html
I could go on but I think you guys get the idea. If MAF reports back a frequency, AEM FIC can't touch it. Go for the o2 imo.
Last edited by Witt; 02-14-2008 at 12:17 AM. Reason: Automerged Doublepost
#100
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If its 0-5 its analog. I'm quite certain it can't clamp a GM MAF.
A work around is to build a larger diameter custom intake pipe. More airflow will go by at a lower frequency.
http://forum.aempower.com/forum/inde...c,20963.0.html
http://forum.aempower.com/forum/inde...c,21284.0.html
http://forum.aempower.com/forum/inde...c,20502.0.html
I could go on but I think you guys get the idea. If MAF reports back a frequency, AEM FIC can't touch it. Go for the o2 imo.
A work around is to build a larger diameter custom intake pipe. More airflow will go by at a lower frequency.
http://forum.aempower.com/forum/inde...c,20963.0.html
http://forum.aempower.com/forum/inde...c,21284.0.html
http://forum.aempower.com/forum/inde...c,20502.0.html
I could go on but I think you guys get the idea. If MAF reports back a frequency, AEM FIC can't touch it. Go for the o2 imo.