tunercat(% change to fuel air ratio v.s rpm @wot)

is this the only place on tunercat to change the air fuel ratio? changed this form -6% to -8%,-10%,-11% in some area's, made very little change to mv, car is still very rich,955mv to 910mv, I need to get down to 830-850mv(peak power) % 850-870 peak tq, any suggestions?

Multiple posts regarding tuning with our 02's. You can search for them, but the bottom line is this: you cannot tune with our 02's.

your 850mv is different from my 850mv and the true AFR it will be at. My suggestion is to wideband test it.

Ben

I was going to leave the topic of tuning with O2s alone...but :D

when you don't have a dyno facility or a wide-band in your backyard....you use what you can. Reading the plugs on an unleaded fuel/FI isn't going to tell the story (NA).

What gives..? Why are you giving us grief over using our O2s to get the tune closer.....? It has been my experience that many have used them as a general guideline and actual testing is needed to determine what each car likes.

Given, the O2s are not accurate and what your car likes and what my car likes are two different things, but there are some consistencies. I bet most on here would concede that 950mV+ is a bit too rich. I would also venture to say that most would agree that 820mV and less are pushing the lean window a bit much. Somewhere in the middle is a good area to be. Is it exact...no. Do we know that....yes. Are you being even remotely helpful in assisting us in working with what we have to reach a reasonably-accurate goal....hell no.

Last week I asked for a basic, simple direction on best practices for a HOT-cam, stock heads car. I got squat. I did my own thing. Car ran about the same mph, but .15 slower. I took too much out of the power enrichment (the % @WOT vs RPM and temp tables). The car wouldn't 60ft well and was quite weak till half track. That's one lesson learned that I might have avoided if someone had given me a bit of the advice I'd asked for.

There are few on this board that know it all or even have all the resources available needed to do the best possible work. Some of us might not even know how to best word a question/response in order to get our need/point to the reader. The main thing is to try and help one another to get the job done with what we have and know. Inferring that folks are not doing it right because they don't have the most sophisticated tools for the job isn't being a friendly Internet neighbor.

And I'd like to apologize for hijacking the post.

to answer your question....no, it's not the only place. The VE tables are an excellent place to make changes but it requires much more testing and time (it's easier to completely hose yourself with the VE and MAF tables). I attacked the PE as a first-step in testing before moving to the VE and MAF tables to make adjustments. It's much safer as the PCM will continue to try keeping the proper A/F going. If you play with the other two tables and make wide-sweeping changes without some data giving you direction....you might need a broom and dustpan later.... All this is for NA of course.

Originally posted by dougg01
I was going to leave the topic of tuning with O2s alone...but :D

Given, the O2s are not accurate and what your car likes and what my car likes are two different things, but there are some consistencies. I bet most on here would concede that 950mV+ is a bit too rich. I would also venture to say that most would agree that 820mV and less are pushing the lean window a bit much. Somewhere in the middle is a good area to be. Is it exact...no. Do we know that....yes. Are you being even remotely helpful in assisting us in working with what we have to reach a reasonably-accurate goal....hell no.

to answer your question....no, it's not the only place. The VE tables are an excellent place to make changes but it requires much more testing and time (it's easier to completely hose yourself with the VE and MAF tables). I attacked the PE as a first-step in testing before moving to the VE and MAF tables to make adjustments. It's much safer as the PCM will continue to try keeping the proper A/F going. If you play with the other two tables and make wide-sweeping changes without some data giving you direction....you might need a broom and dustpan later.... All this is for NA of course.

Doug,

Well, lets just say we will never agree regarding the 02's, but that is cool.

As for not being helpful, well here is a post where I and others cover AFR tuning in PE. http://web.camaross.com/forums/showthread.php?s=&threadid=143169

My intent from my first post was to help comprehend the inaccuracies of using our 02's - that is it. That to me is helpful to anyone that does not understand this. I guess I should not assume that others have found secondary sources in trying to tune at WOT.

Ben

Originally posted by 95Blackhawk
Well, lets just say we will never agree regarding the 02's, but that is cool.

what...agree they are inaccurate and vary from car to car and even sensor to sensor...? I agree. I also agree that's my only source for A/F data other than plugs and timeslips (BLMs too).


I guess I should not assume that others have found secondary sources in trying to tune at WOT.
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Found...they are available....not free and for a quality shop....not local. I have other responsibilities and I can't take time out to visit the dyno....make passes.....examine the data.....tune.....return to the dyno and repeat the procedure again until I am optimal. If it was 20 minutes away....it might be more feasible..... I'd thought about either and EGT or wideband gauge.....neither of which are cheap.....might go that way eventually. For now....I'd rather be a moron and use the values my car spits out now since it fits my budget.

how can you possibly tune for wot using the o2s. the computer doesnt even see them in open loop. some body has got to explain this to me. if you could use the o2s for tuning wide open throttle you would not need a wide band o2.

Doug,

Did you read my attached forum? That gives a way I was able to get accurate results without going to a wideband.

I just hope others are able to recreate what I was able to accomplish in order to confirm my findings. I am not sure if you have a MAF since you talk of VE, so it may not apply to you.

Ben

Originally posted by dougg01
when you don't have a dyno facility or a wide-band in your backyard....you use what you can. Reading the plugs on an unleaded fuel/FI isn't going to tell the story (NA).

What gives..? Why are you giving us grief over using our O2s to get the tune closer.....? It has been my experience that many have used them as a general guideline and actual testing is needed to determine what each car likes.

I can never leave an argument alone, as long as it's all in good fun. ;)
Tuning with O2's is really a waste of time...and this has been beaten to death. I understand that if you don't have a dyno local to you that you're kind of screwed. But O2's aren't the answer. Get a do-it-yourself wideband or EGT as either one of those will work so much better than trying to use O2's.

Given, the O2s are not accurate and what your car likes and what my car likes are two different things, but there are some consistencies. I bet most on here would concede that 950mV+ is a bit too rich. I would also venture to say that most would agree that 820mV and less are pushing the lean window a bit much.

I won't concede that. Where did you get 950 and 820 from?
Odd, I've seen 940-960 be 13:1 on a wideband a couple of times.
I've also seen 980 be 12.3:1.
I've also seen 920 be 14:1.
Should I go on?
And all of these runs are logged with datamaster and are on one of my laptops, just not sure which one.
My car went from 930 down to 880 as rpm increased on my car with the stock programming. I've raised the injector constant a little to help lower injector pulsewidth for part throttle, and then raised pe vs. rpm to richen it back up a little. I don't care if it's perfect since it's just my daily driver...I just want it safe when I jump on it. Well, now it pukes a little black smoke when I first hit it...yet O2's are still around 880mv. Real consistent. :rolleyes:

Somewhere in the middle is a good area to be. Is it exact...no. Do we know that....yes. Are you being even remotely helpful in assisting us in working with what we have to reach a reasonably-accurate goal....hell no.

Yeah, I suppose somewhere in the middle is safe. But what are you in the middle of?

Last week I asked for a basic, simple direction on best practices for a HOT-cam, stock heads car. I got squat.

I didn't see that post. Sorry. I'm sure I could have helped you out somehow. Are there any questions you still have that you'd like answered?

That's one lesson learned that I might have avoided if someone had given me a bit of the advice I'd asked for.

Best way to learn is by your own mistakes. I don't think it's right that you bitch that we didn't give you the advice you asked for though.

Inferring that folks are not doing it right because they don't have the most sophisticated tools for the job isn't being a friendly Internet neighbor.

Right. But letting them know that what they are doing isn't helping them is the best we can do. What if some poor guy keeps leaning out his pe vs rpm because he doesn't see his O2's where he wants them...then something bad happens to the car?
Would you like him to come back to you saying that you suggested he keep removing fuel until his O2's read a certain voltage?
Neither would we. That's why very few people here will suggest using your O2's for anything.

The VE tables are an excellent place to make changes

:eek: Oh no...let's not start that argument. :)

I attacked the PE as a first-step in testing before moving to the VE and MAF tables to make adjustments. It's much safer as the PCM will continue to try keeping the proper A/F going.

So in PE mode the computer is trying to maintan a certain a/f ratio? Interesting.

If you play with the other two tables and make wide-sweeping changes without some data giving you direction....you might need a broom and dustpan later

Exact same thing if you use O2 voltage to tune.

I should just put the stock prog on my car and sell all the go-fast stuff cause this is getting to be a bit much for me. I miss metering rods and advance springs.....of course I've been fooling with this stuff long enough that I probably couldn't tell the difference between a jet and a power valve by now.

I am not trying to start crap though. I want some answers because apparently all this time I ahve been mislead to believe the O2 values had some value. Should I be running in open-loop all the time since the O2s don't carry any weight....? I too have seen changes that I've made not make any significant impact on O2 values. I erroneously attributed that to compensations made by other parameters that I may or may not be able to adjust. I do not fully understand all the interplay with tables that I can adjust (me personally), the other I can and don't, and the ones I cannot adjust (not available in tunercat).

Not sure what I am going to do now since many things I thought I did know have been revealed to me as myth. I might need to stop using diacom-p for anything other than confirming shift points, idle operation and timing. Using it as a tuning tool is probably folly since values I used to consider value-added are not since the PCM uses O2 values for determining a few things. Maybe I'll just go back to the old methods....

There was a thread on reading plugs and if you do it like it should be done.....I think you could get good results on an FI car. The key is shutting the car down at the point you want to tune for and checking the plugs without running the car further.... We used to always hit the kill at the end of a pass (or earlier) on T-n-t nights (back in the carb'd days) and coast off into the grass on the return road (safely away from harm...). Have a socket and wrench to yank a handful of plugs once the headers cool. I carried 4 extra plugs to put back in so I could drive back to the pits to properly look at the plugs I removed. That coupled with time slips corrected for climate (assuming the testing was done at the same track all the time) and you got pretty close. Problem is....on my car I'd probably only be able to get 2 or maybe three plugs off at the end of the track since other others require direct contact with the header to remove. Maybe I could just burn my hands....you know....take some pain for the cause and all that. :)

I'm really at a loss. If I was spraying (which I won't) I'd be running an EGT. The only way I can think running an EGT or wide-band would help me is if they came with a data-logging function and those systems appear to be expensive. Maybe a trip to the dyno shop will be worth it anyway... I'll take the data gathered from that and make changes to hopefully get closer than I am now. Just about anything could be an improvement.

Maybe I can just sell my tunercat stuff and get a MAFT+ to tune by ET and mph. Adjust till I get the best results. Much more simple than the crap I see before me now.

thanks for the inputs. :D

WoW! You guys are vehement

Awww man, I wasn't trying to discourage you or anything in any way.
Keep the tunercat. Being able to adjust timing at any map vs rpm is worth it. Also, once you do get the car on the dyno you can get the fuel curved nailed pretty quick. I'd say to do timing and fuel you sould be done in 2 hours and probably 8-10 pulls.
Running open loop won't fix anything. You'd just have total control over fueling under all conditions with the open loop afr table.
All I was trying to say was that you're really chasing your tail by trying to tune by O2 voltage.
Didn't know my input/opinion would scare you away from the world of fuel injection forever.

Also, I still don't understand how some people can spend thousands of dollars on parts for their cars but not want to spend the money to get it to run properly. And I'm not talking about anyone in particular, just that group of people in general.

thousands of dollars...? :confused: Tell me where they are and I will spend it...

I sell, trade and beg for stuff. Just keeping the ole' girl running can be an experience in pain when the $$$ are needed. Once the car got paid off....the spicket ran nearly ran dry.

Tuning at the dyno facility might not be feasible. I'd need my desktop PC since that is my tuning station. 2 hours at the dyno facility....not sure I could swing that. It would need to be done in mulitple trips.

Originally posted by 97Z-M6
how can you possibly tune for wot using the o2s. the computer doesnt even see them in open loop. some body has got to explain this to me. if you could use the o2s for tuning wide open throttle you would not need a wide band o2.

The PCM can "see" the O2 sensor values at WOT, and you can read them with a scanner. But the PCM does not do anything with the O2 sensor values at WOT... it just "sees" them, but doesn't respond in any way. There is feedback, just no reaction.

The argument arises out of the fact that a narrow-band O2 sensor is more sensitive to operating temperature at 800-1000mV than it is to real changes in the A/F ratio. A small temperature change can mask a significant change in A/F ratio.

Originally posted by Injuneer
The PCM can "see" the O2 sensor values at WOT, and you can read them with a scanner. But the PCM does not do anything with the O2 sensor values at WOT... it just "sees" them, but doesn't respond in any way. There is feedback, just no reaction.

The argument arises out of the fact that a narrow-band O2 sensor is more sensitive to operating temperature at 800-1000mV than it is to real changes in the A/F ratio. A small temperature change can mask a significant change in A/F ratio.

Fred...you're cool. :cool:

So, does anyone know what the temperature variance is and can it be tracked...? Is there a way to possibly put the data into a correction table to provide a reasonably-accurate reading...?

Originally posted by Injuneer
The PCM can "see" the O2 sensor values at WOT, and you can read them with a scanner. But the PCM does not do anything with the O2 sensor values at WOT... it just "sees" them, but doesn't respond in any way. There is feedback, just no reaction.

The argument arises out of the fact that a narrow-band O2 sensor is more sensitive to operating temperature at 800-1000mV than it is to real changes in the A/F ratio. A small temperature change can mask a significant change in A/F ratio.

you re right as usuall thats what i meant to say i misspoke sorry. for the confusion. becuase i look at them with data master.

Fred.....Fred is never wrong...except for what does and does not belong in Advanced Tech.:p :D

Now lets see if we can narrow down this temperature-sensitivity and find a way to deal with it or use it to compensate for the reported values. Anyone running an EGT and can see what the O2s are seeing for temps and A/F...? I'd imagine all conditions and tuning will need to be reported because so many things can contribute to the temps.

Geez, I might learn something today after all.

Originally posted by dougg01
Fred...you're cool. :cool:

So, does anyone know what the temperature variance is and can it be tracked...? Is there a way to possibly put the data into a correction table to provide a reasonably-accurate reading...?

No... I'm just old and senile.... :D.

There are charts available that show the output of the sensors as a function of lambda (A/F ratio) and operating temperatures. It gets even more complicated, because of "hysterisis" in the device... if the air fuel ratio is swinging from rich to lean, you get a different mV output than when it is swinging from lean to rich.

I can give you a reference on one of the "auto electronics" texts that has a good chart.

Originally posted by Injuneer
No... I'm just old and senile.... :D.

Senile.....? Okay, let's test it. Give me your car...?

I can give you a reference on one of the "auto electronics" texts that has a good chart.

And I've got to say the magic word......? Please. :)

Of course, this is useless unless we have a temperature, another reasonably accurate thingy, by which to scan the chart and get another rough estimate as to where we are. FAST sounds better and better all the time.

Scratch off the car Fred.... Senility test #2.....can you give me $3,000.00...? (should I word it as a question or statement when directed to the elderly impaired..? BTW. Those kind can't see inside punctuation so we can talk about them in here). :)