Thread: AFR and Timing Tuning (02 Regal GS 223k!!!)

Correct yes open loop =wot and pe, and yes no worries if you're trims are very close.

Your Afr is dependent on your stoich Afr value.

Originally Posted by 91parkave

Correct yes open loop =wot and pe, and yes no worries if you're trims are very close.

Your Afr is dependent on your stoich Afr value.

On a cold start the car is in open loop until it warms up which turns into closed loop.

Under normal driving it is still in closed loop then correct?

Once PE/wot is entered open loop is then entered until you take your foot out which then closed loop is entered again?

Stoich is obtained with the quality of fuel and what it is set at correct? (14.7)

Yes you are correct on all counts

Stoich is whatever you set you're fuel you're too. I set mine to 14.68.

Originally Posted by darkhorizon

No, you should never do this.



Maf tuning in this manner gets you nowhere, other than a janky ass maf curve based on whatever your o2 sensor, engine diagnostics, evap status, egr status, air temperature, feels like displaying in the LTFT at the time.



You want to leave the LQ4 file completely stock if at all possible. Changes here are the absolute worst place to make adjustments for "mystery" things being wrong with your tune. The maf sensors almost never have variance from car to car unless you have an obvious air filter issue... which I usually handle in the IFR value, as its the mathmatically easiest way to adjust a logarithmic equation that is the maf curve.



Its not preference or anything.. tuning the maf is just wrong if you have a stock maf sensor. If you have trouble with your commanded afr matching actual afr in the WB, the easiest way to adjust for this error is in PE, as it is not controlled by the narrowband.

That is what I have to work with. If this matters I have no egr or evap.

So I should put the lq4 maf table and don't touch it and then what?

How do I go about getting my trims in check? What histogram would have to made for that? Don't a lot of people modifty the maf table to get the trims in check? That is why they do this, or no?

For afr at wot which PE would I modify if not the maf like others? As seen are stock vs what its at now. Some say do it this way some say do it that way. Especially the tuner guide contradicts some.

You read made sure you smooth your maf after changes.

I would like to know how you approach this type of thing. I am not debating with you.

Originally Posted by darkhorizon

You shouldnt have to. Trims do stuff.. its what happens. If they are doing dumb stuff then you have a mechanical issue (maybe your maf tube is stupid) so you will have to adjust a bit... as said before its easier to do that outside of the maf table typically.




Every tuner guide made is completely wrong. Dont look at them for any value. People that "tune" are also not experts in any form... the guys that write the HPT software in fact have no idea what they are doing unless they spend significant time looking at complicated de-compiled assembly code. Even at that point its hard to see a clear picture of whats going on.

Where this "tune fuel trims to 0" idea came from is just stupid if you think logically about it.

How do you tune a cammed w-body then? Lots and lots of air being drawn in just for example.

How would you get my issue dialed in? If you are adding 6psi or so more than stock then there will be an adjustment needed. Like wise bigger injectors will cause trims to jump.

Is this your own little secret of the right way to things? Not willing to share?

Originally Posted by darkhorizon

NIC cam for example works great with stock maf... commanded PE matched actual PE afrs dead nuts every single one I have tuned right out of the box.



You have a mechanical issue.. the maf sensor installed does not match the pcm maf table.




boost is not measured for fueling reasons in a 3800pcm.



Bigger injectors get different IFR values... its "tuned" when you put the correct values in. "crazy" sized injectors (80+lb) can cause some interesting issues by increased deadtimes or less linear flow rates, but its usually not sigificant enough to worry about, or you could adjust it in the maf on a per car basis, without using the narrowband.



I share all my "secrets". The "secret" is nerds sit around the internet reading 10000000000 things on tuning and are convinced its a 223 step process... its no harder than screwing a new air filter on in reality.... The hardest and really only "tuning" part is figuring out what AFR you want to run in PE... and thats something you can ask experts like myself or figure out on your own.

If your commanding 11.5 for your NIC cam and getting 11.5 then which table are you modifying? RPM vs Time?

Do you personally ever touch PE vs TPS?

Am I right when I say it must be one of both of those?

How do I get the correct IFR's then for 42lb injectors (if they are wrong)?

This is a zzp 1.0 I found.

Originally Posted by darkhorizon

I built my own transmission friendly PE vs RPM (vs time i guess) table... It removes the time part and focuses on dumping extra fuel at the shift points.



I do some fancy crap on the turbo drag cars, typically not much if any on SC cars.



PE vs coolant temp is the "main" commanded PE afr table.



I use the narrowband to help... Eyeball the trims to see what direction they generally go and go from there. (between -10 and -6 most the time? subtract 7% and consider it tuned) I have my own math saved off thats usually close enough for me not to ever adjust them after the fact unless someone is paying me alot of money or they are convinced i need spend 3 days working on it and I want to look busy tuning their car.

Remember fuel trims take a few power cycles to learn correctly, so go with a base flash and drive around for awhile... throw the gauge up on the scan tool and glance at it while you are driving around to get an idea of how much adjustment you might want to make... tune WOT/PE a while after you make the IFR correction.

RPM vs time I understand the rpm but how do you know when/where to adjust to in the sec area?

PE vs TPS will having a number of 1.300 up to 20% net better mpgs at all?

How do I go about knowing how far to adjust the injectors 0-100 kpa wise? Also where do these numbers come from? I am sure I can find a few different IFR's charts in random 42.5' tunes.

Is there such thing of the correct IFR chart? Or will there be a baseline that will have to be modified?

Should I set my commanded afr from 11.5 down to 11.2 in Base vs ECT across the whole board?

As for the IRF table. How do you go about tweaking this? Doesn't a bigger number lessen fuel? Is there a general percentage to add onto a stock IFR value for a closer correct rate of 42.5's?

This makes no sense you tune maf because you have a LQ4 maf in a non factory installation. Too easy to do. Why you would skew perfectly good injector data makes no sense in this situation not to mention saying the HP tuners software writers don't know what there doing. I'm pretty sure there credentials and experience far. Exceedes daarkhorizon. That being said there's more than one way to get to your goal. If anything try both methods see what works well for you.

If it were me input proper injector data work in maf and ve and go from there

Originally Posted by 91parkave

This makes no sense you tune maf because you have a LQ4 maf in a non factory installation. Too easy to do. Why you would skew perfectly good injector data makes no sense in this situation not to mention saying the HP tuners software writers don't know what there doing. I'm pretty sure there credentials and experience far. Exceedes daarkhorizon. That being said there's more than one way to get to your goal. If anything try both methods see what works well for you.

If it were me input proper injector data work in maf and ve and go from there

I'm not taking sides. Im a bit confused on what/what not to do. I just don't know where my injector data came from or if it is right. I know you sent me that spread sheet as I posted a few pages back but the values just didn't make sense.

You gotta part number for your injectors? Look on the injector itself for a part number

Originally Posted by 91parkave

You gotta part number for your injectors? Look on the injector itself for a part number

I don't know exactly what they are. I know they are 42.5's

#01D030B



Google came up with this

http://www.hptuners.com/forum/showth...ectors-support

http://shop.zzperformance.com/store/...jectors-6.aspx

How are the initial #'s found though? Going from stock to bigger injectors to start off where you need to be.

I can't seem to find the post now but I thought I came across you saying 21% would need to be modified for a 42 and 19% for a 39#.

I didn't understand.

Originally Posted by PWNED

How are the initial #'s found though? Going from stock to bigger injectors to start off where you need to be.

I can't seem to find the post now but I thought I came across you saying 21% would need to be modified for a 42 and 19% for a 39#.

I didn't understand.

I'll send if I can get you the correct fuel injector data..usually when you have Delphi injectors they have a platform that they came installed on. Usually you can download the stock hpt file out the repository and copy paste that correct injector data

Originally Posted by 91parkave

I'll send if I can get you the correct fuel injector data..usually when you have Delphi injectors they have a platform that they came installed on. Usually you can download the stock hpt file out the repository and copy paste that correct injector data

They say Delphi but then zzp says lucas. Besides finding a vehicle with them there must be an equation to get you to the same #'s just incase.