so even with a wideband and an AFC to tune for a correct a/f ratio you still need something else to make it better is that what your saying? like how you said he has an egt and a wideband. what does the egt do in that instance?
wideband
- Thread starter mkiii88supra
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jimi87-t said:
Lol yeah, I get the distinct impression you don't have nearly the problems with your car others do. That intake setup of yours also proves you're a stickler for detail
.mkiii: EGT is Exhaust Gas Temperature. It's usually measured with a type K thermocouple. There is a direct corelation between EGT and mixture so it can be helpful for tuning as long as you understand the relationship. It's simply looking at another way to determine mixture but also has limitations. You need to search around this site or Google some of this stuff to gain an understanding of the basics.
EGT rises as you approach stoich and then falls so you can be either on the rich or lean side of "peak". About 200 degrees or so on the rich side is best power while 100 or so on the lean side is best economy. There is also a limit you don't want to exceed. The problem with EGT is it's an aggregate of all cylinders unless you have a probe in each exhaust runner. Course, that's also true of an O2 sensor.
Most car guys use a single EGT but in airplanes we use what's called an engine analyzer. A neat gadget that displays and tracks EGT in each cylinder in bar or digital form. Google JPI Instruments or Electronics International to see examples of these things. They're not cheap but you can get them used. I had one on a car of mine for several years. I use lots of aerospace stuff on my cars since I have it laying around.
You guys are all about making power and fuel be damned but as long as the induction and fuel delivery systems are designed properly (to minimize the spread between mixture, and thus EGT) in each cylinder it's possible to go in the other direction.
Your stock O2 sensor is designed to keep the mixture at stoich during cruise right? What if you could change that? What if you could have the engine run 100 degrees or more lean of peak EGT? Your fuel economy would dramatically increase and the engine would run cleaner and cooler. Since the throttle and mixture are independent in piston powered aircraft these are the same techniques taught to every pilot that flies them. Jets are different (although EGT is still critical) but running the mixture lean of peak EGT, even at 75% power, in piston aircraft is a common and correct procedure and woe be the pilot who forgets to do it.
I did this to a car. Since a car engine loafs at around 20-30% power on the highway it's not dangerous to lean it past peak EGT. The car I used had a simple engine ecu so I modified it to provide an offset from controlling at stoich. This gave me a "dail a mixture" knob on the dash. By measuring all 6 EGTs using an aircraft engine analyzer (a simple 6 point EGT probe would've also worked) I could set that puppy well lean of peak and get 25-30% better highway mileage than stock. The trick is it only works as long as you're steady state but for long stretches of highway under crusie control it works as well as it does in airplanes. In fact, if you really want to understand mixture and it's effects on an engine study the stuff pilots are taught or read the tech articles on those websites.
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so i know that LM-1 and i think Ians Wolf does data logging and fuel mapping? i was also looking at the maftpro.. i dont think it does mapping, it may but it makes it easier somehow? i was also looking at the aem 6-1, but i think its just for monitoring , not tuning?
what other systems are available out there. and what would you recomend for someone like me who is a novice to tuning? im going to research it all before i buy, but i would like to know what i should be looking for. the fuel mapping is intimidating, but i dont think its beyond my skills,, if i take the time to learn it??
what other systems are available out there. and what would you recomend for someone like me who is a novice to tuning? im going to research it all before i buy, but i would like to know what i should be looking for. the fuel mapping is intimidating, but i dont think its beyond my skills,, if i take the time to learn it??
Joel, I'm no a whiz on modding so I'll leave it to the guys here who know but no matter what you do, the fact that you're willing to do your homework and learn puts nothing beyond your reach. It's what separates the pros from those with endless frustration. There is a lot of talent here if you're able to cut through the BS. Search Google for wideband stuff, lots out there. There are even sites for rolling your own controller. Good luck.
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Joel, here is a simple break down on what is going on, If I leave any thing out I will have to clarify tomorrow.
In order to run more boost safely you need to take control over your ECU, so that you can tell it (or trick it) to add or take away fuel. In order to do this you need a piggy back. That is what a SAFC or a MAFTPRO is. Fuel mapping is done in the piggy back. The map is telling the ecu when to add or subtract fuel.
In order to know what to set the map to you need a wide band to show you what it is running at, then you can see your high and low spots then program the map in the Piggy back to compensate. The WB does not do maps. It is just a gauge to show you what is going on. This is where you need data logging, like in the LM-1, or some piggy backs and most stand alones also have logging. You download that log onto your PC and view the "line" and then go into your mapping software and add or subtract fuel where need be. (it gets way more complicated with a stand alone, as you need to map everything, such as timing, so we will not go there right now)
I will add to this tomorrow, it's bed time. But that should should help some for now.
In order to run more boost safely you need to take control over your ECU, so that you can tell it (or trick it) to add or take away fuel. In order to do this you need a piggy back. That is what a SAFC or a MAFTPRO is. Fuel mapping is done in the piggy back. The map is telling the ecu when to add or subtract fuel.
In order to know what to set the map to you need a wide band to show you what it is running at, then you can see your high and low spots then program the map in the Piggy back to compensate. The WB does not do maps. It is just a gauge to show you what is going on. This is where you need data logging, like in the LM-1, or some piggy backs and most stand alones also have logging. You download that log onto your PC and view the "line" and then go into your mapping software and add or subtract fuel where need be. (it gets way more complicated with a stand alone, as you need to map everything, such as timing, so we will not go there right now)
I will add to this tomorrow, it's bed time. But that should should help some for now.
thanks jimi, i was confused on the diff between a piggy back and stand alones...that does clear it up a bit, i have been reading about these on here for a while but only recently is some of it starting to make sense to me... (too many initials) lol.. , so i never really understood what i was reading. and the websites are confusing as hell. im sure this has been covered over and over again on here. so thanks for taking the time...
ill keep searching also,
ill keep searching also,
Yeah Joel, the difference between a stand alone and a piggy back is, a piggy back taps into the stock ECU to be able to over ride some of the ECUs functions. A stand alone totally replaces the stock ECU.
this is very informative. thanks again guys. so i have been looking around on the forums and i saw that there is the group buy for the AEM 6in1. now will this do all the monitoring and everything that i need to tune properly? what else would i need with this to make the setup work?
(i already have a AFC-II)
(i already have a AFC-II)
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From what I've read the AEM 6 in 1, is just a basic gauge + o2 sensor controller. This will not allow you to data log, this is really a necessity in order to tune properly. You need to see the graph of what is going on and not just have a nice flashy gauge. The AEM is fine IF you have other means of data logging, as it can send the output to a data logger for recording.
well im not going be tuning myself but your saying that someone else would need the logging to be able to tune the car. if so then what is the best wideband?
If you are taking it to a shop to have it tuned, they will have all the monitoring equipment needed to tune with.
that aem will work in a maft pro thus you can do data logging.... and i believe that gb is over...
well lets see if someone can tell me what would be best for me. (im sure someone can)
i have full 3in exhaust no cat, intake, lexus AFM, 550's, 255lph pump, fmic, hardpipes, HKS SSQV, HKS headgasket, freshed up motor, greddy boost controller, S-AFC, apex turbo timer.
now when i get the car running i want to take it to get dyno tuned so i dont fuck anything up. so i wont be touching the AFC or anything when they are done. now what wideband(if needed) would be best suited for what i need. thanks in advance guys
i have full 3in exhaust no cat, intake, lexus AFM, 550's, 255lph pump, fmic, hardpipes, HKS SSQV, HKS headgasket, freshed up motor, greddy boost controller, S-AFC, apex turbo timer.
now when i get the car running i want to take it to get dyno tuned so i dont fuck anything up. so i wont be touching the AFC or anything when they are done. now what wideband(if needed) would be best suited for what i need. thanks in advance guys
Joel W. said:
The LM-1 is not a piggy back. It is the WB o2 controller and data logger. I will be going with a Maft-pro after the motor is nice and run in.
bigal0043 said:
I didn't know the Maftpro did logging, thanks. That should help people out picking out a WB controller.
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mkiii88supra said:
It would not be needed per say in that case, but you would be fine with the AEM, seeing as you will not be tuning it yourself. And it would be a good idea to run one just to keep an eye on you AFR.
EDIT: also Innovate also makes the LC-1 add to that their gauge and you would have a very simple and nice WB. Their gauge is the best one IMO. (but it can not be use with anything other than an Innovate product) Here is a link to a package for both:LC-1 + XD-16 combo Also don't let the "stand alone" term confuse you, this is NOT an ECU.
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