slow2000z28

just the basics so far...

IDEAL
(Rich) (Lean)
Base (ltrims) - 0 +

(Lean) (Rich)
WOT (O2's) .800 .880-.890 .900

(Rich) (Lean)
A/F (WOT) 12.5 12.8 or .9 13.3

A/F (non-WOT) PCM will try to maintain 14.7:1



AFR Info

9.0:1 BLACK SMOKE (NO POWER)

11.5:1 RICH BEST TORQUE @ WOT

12.2:1 SAFE BEST POWER @ WOT

13.3:1 LEAN BEST TORQUE @ WOT

14.6:1 STOCHIMETRIC AFR ( CHEMICALLY CORRECT )

15.5:1 LEAN CRUISE

16.5:1 BEST FUEL ECONOMY

18.0:1 CARBURETED LEAN LIMIT

22.0:1 EFI LEAN LIMIT



courtesey: hp tuners help files


ill post more as i compile it

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QTP LT's, QTP ORY w/ Cut outs, ported tb, ported Maf, msd wires, 4.10 gears, upgraded axles and drive shaft, built Rockland T-56 trans, t/a rear girdle, centerforce clutch, cold air intake, flowmaster, and standalone computer tunning from HPTuners
weiand intake on the way and sts turbo kit hopefully by this spring.

misnblu

It's confusing at best.
Plus, it really tells you nothing of true a/f tuning.


This is really confusing.
(Lean) (Rich)
WOT (O2's) .800 .880-.890 .900

(Rich) (Lean)
A/F (WOT) 12.5 12.8 or .9 13.3

I don't have my wideband yet but do have a scan gauge to register numeric reference of wot a/f.
I'm running about .920-.925 at wot with 42psi of fuel.
(or .9 13.3) Does this mean I'm running 13.3 a/f at .90??

See the confusion??

I'd like to know more and if you could post a better reference, would be helpful.
Something else to consider is the amount of knock retard you have when you do a/f tuning.
This is what I'm working on now with the scan gauge showing knock retard in degrees and actual real time voltage from the 0-1volt a/f reading of the O2 sensor through the scan gauge.

Misnblu

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ButcherRacing

Probably just petty but I read that the stochimetric ratio was 14.7:1 not 14.6:1 but I could be wrong.

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misnblu

Correct.

Misnblu

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slow2000z28

technically it is 14.7 but really a rounded up number from 14.67244 to 1
as far as the other part...
(Lean) (Rich)
WOT (O2's) .800, .880-.890, .900 -the first numberf is the lowest it should be the middle numbers are the average and best they should be, and the last is the highest. all numbers are in the standard millivolts that stock o2 sensors put out.

(Rich) (Lean)
A/F (WOT) 12.5, 12.8 or .9, 13.3- the same as above applies here, first is lowest, middle is hoped for, and last is highest. a basic AFR guage will tell you these numbers

A/F (non-WOT) PCM will try to maintain 14.7:1
any more questions?

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QTP LT's, QTP ORY w/ Cut outs, ported tb, ported Maf, msd wires, 4.10 gears, upgraded axles and drive shaft, built Rockland T-56 trans, t/a rear girdle, centerforce clutch, cold air intake, flowmaster, and standalone computer tunning from HPTuners
weiand intake on the way and sts turbo kit hopefully by this spring.

slow2000z28

[quote=

See the confusion??

I'd like to know more and if you could post a better reference, would be helpful.
Something else to consider is the amount of knock retard you have when you do a/f tuning.
This is what I'm working on now with the scan gauge showing knock retard in degrees and actual real time voltage from the 0-1volt a/f reading of the O2 sensor through the scan gauge.

Misnblu[/QUOTE]

i will gladly post the whole tunning guide but it will be extremely long. i cant post a web site bc it didnt come from a web site it was emailed to me from a moderator from hp tuners. ill search to see if i can find it as a post on there forum

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QTP LT's, QTP ORY w/ Cut outs, ported tb, ported Maf, msd wires, 4.10 gears, upgraded axles and drive shaft, built Rockland T-56 trans, t/a rear girdle, centerforce clutch, cold air intake, flowmaster, and standalone computer tunning from HPTuners
weiand intake on the way and sts turbo kit hopefully by this spring.

slow2000z28

http://www.hptuners.com/forum/showthread.php?t=4742
http://www.hptuners.com/forum/showthread.php?t=5573

try these from hp tuners for your application misnblu

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QTP LT's, QTP ORY w/ Cut outs, ported tb, ported Maf, msd wires, 4.10 gears, upgraded axles and drive shaft, built Rockland T-56 trans, t/a rear girdle, centerforce clutch, cold air intake, flowmaster, and standalone computer tunning from HPTuners
weiand intake on the way and sts turbo kit hopefully by this spring.

misnblu

Incorrect.
I'm just getting started.
First with the stock o2 and afpr along with my scan gauge to reference actual stock o2 voltage with knock retard in degrees so that I know when I'm having knock.

Later, I'll be getting a wideband controller, the NGK AFX unit and tie the analog output to the scan gauge I have so that I can datalog my a/f and set the best a/f I can until I get my PTPerformance FTM fuel management controller.

HPTuners will be next and should then have a true 14.9 second ride that will be fully tuned n/a style with turbo parts coming in one by one.

Then, heh, it's into the 12's with a fully custom built engine, turbo system that will give Cavaliers a little respect in my local area.

Thanks Slow for the links and I'll definitely check them out and see what I need to do to get the car tuned out.
With the newly installed MSD DIS-2 and Royal Purple oil, runs strong for 192,000 miles on it.
This will be good information even though I've still got the stock o2 sensor to work with but have enough tools to make sure I tune it correctly for wot and be safe.

Misnblu

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misnblu

Ok, so what I'm reading with your post on this, my .920 is running lean, yes??
If so, I need to add fuel with more pressure.

I dropped from 42psi which was reading .920 on the a/f voltage and further dropped the pressure to 40psi. It still reads at wot .920.

The car just seem to run better at 40psi overall and seems to have better driveability over a hight psi.
I'll wait for your reply on this before I go any further with this.

Misnblu

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slow2000z28

correct, you are on the rich side of the scale, id tune out some fuel if possible, remember lean makes more power than rich, but be carefu not too lean. if you cant lose anymore fuel then id see about getting soem more air in there to help compensate. ypui say you have msd ign. so that should help compensate for the richer mixture too. a hotter spark plug if your still n/a. adjust timing for the richness..... only if you must.

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QTP LT's, QTP ORY w/ Cut outs, ported tb, ported Maf, msd wires, 4.10 gears, upgraded axles and drive shaft, built Rockland T-56 trans, t/a rear girdle, centerforce clutch, cold air intake, flowmaster, and standalone computer tunning from HPTuners
weiand intake on the way and sts turbo kit hopefully by this spring.

misnblu

So if .92 is rich, then I'll try dropping the fuel pressure to 38psi.
I've had it at 38psi before and again, the car seemed to run better overall and in driveablity.
I'll adjust it lower to 38psi, drive home tonight and get a few readings and see where I'm at.

Again, I know the stock o2 sensor is limited with tuning but I'm just trying to get better overall power while maintaining no or low knock levels.

I'll let you know what it reads later.

misnblu

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misnblu

I dropped the psi to 38, let the car warm up completely to about halfway home and did some runs.
I datalogged one run to see where I was knocking and nothing unusual.
I'm now reading between 910-925 but mostly stays about 910 to 920. It doesn't stay at .920 consistently like it was at 40psi.

I'm going no lower on the psi though.
GM recommends fuel pressure to be about 43 psi or so.

The car runs good but will further tun when I get the wideband.

Misnblu

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slow2000z28

are u running bigger injectors? and when are you checking the o2 reading at WOT or at part throttle? in my case i have a WOT power enrich feature, pretty sure yours does too. this acts in response to the wot signal from the tps. at wot the a/f ratio drops to the factory or tuned setting below 14.7:1. it is this calculation of the new a/f ratio that the o2's are reading. the change doesnt occur at wot but begins at 60% throttle at low rpms, it changes the amoutn that the throttle plate must be open by how high the rpms are. i/e-800-1200 rpms 60% to engage, @ 2000- 3000 rpms it drops to 35% needed to enter the the power enrich mode. also one calculation that you must take into account is the change in timing, as it generally advances on a n/a engine. i tell u all this because simply there is a very complicated calculation going on at wot to obtain the .920mv reading and the only true way to get it down is w/ a tuning software. you would actually have to change something called a fuel multiplier of the power enrich mode to get the .920 down to .890. i/e leaning it out. in return you must lose some timing to keep from detonation. changing your pressure will help slightly but, you really need hp tuners or a comparable software. before forking out 350 for a good wideband id get hp tuners for 600 and btw you can go pretty far w/ stock o2 sensors. i tuned my car w/o a wideband.

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QTP LT's, QTP ORY w/ Cut outs, ported tb, ported Maf, msd wires, 4.10 gears, upgraded axles and drive shaft, built Rockland T-56 trans, t/a rear girdle, centerforce clutch, cold air intake, flowmaster, and standalone computer tunning from HPTuners
weiand intake on the way and sts turbo kit hopefully by this spring.

slow2000z28

pe.txt

this is how the pe table looks on my car

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QTP LT's, QTP ORY w/ Cut outs, ported tb, ported Maf, msd wires, 4.10 gears, upgraded axles and drive shaft, built Rockland T-56 trans, t/a rear girdle, centerforce clutch, cold air intake, flowmaster, and standalone computer tunning from HPTuners
weiand intake on the way and sts turbo kit hopefully by this spring.

misnblu

Hmmmm.
Well, I'm not running bigger injectors, just the stock units.
Also, I'm using short and long trim readings from my scan gauge to set the fuel pressure too.

So far, I'm at 35psi on the fuel pressure with readings of the a/f voltage at .900 and long fuel trims at -3 for idle and about -9.5 to -10.5 at cruise. With throttle, the long term goes down now to -6 or so.
The long fuel trims were at -17 or more for just cruising speed and -10 for idling so it has taken out some of the excess fuel.

Also, the car is running way better than with the fuel pressure at 43psi.
Response is instant and the car now jumps when you go wot. I'm impressed.

But, I don't think I'll go down any further with the fuel pressure.
I've been monitoring knock as well and has none to speak of and have been running premium gas the last few tanks as I've been getting into these adjustments.

What do you think and be honest..
Btw, I'm still investing in an NGK-AFX wideband controller.
With the turbo setup I'm going with, will need it along with HPTuners which I'm also going to acquire.
Misnblu

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