Tuning AF and timing with tweecer.

[mackey]

Well I finally got an LC-1 with digital readout for my car and now I can start tuning the AF. I have got it close with the tweecer RT, but I still have problems with a cold start, and the idle hanging when I come to a stop. I am hoping to figure most of these otu when I get the AF dialed in.

My question is, is the best way to dial the AF ratio the MAF table?

Also after I dial this is what is the best way to dial in the spark tables. I know no pinging should be present but is it mostly guess and check? I've seen a few tables and I'm just wondering how to set it up. I am going to be copying one for right now but would like to do some tweecing to it in the future.

What is the A/F I should shoot for? If going all performance?

Should I change the TB scalar, since I went from stock to 75mm TB?

How do I turn adaptive learning off?

Combo:
TFS H/C/I
Pro-m 80mm
24# injectors
3:73s
MAC shorties, prochamber,flowmasters
255gph pump

 

[WhiteDevil]

To work on my A/f Ratio under normal driving i use EEC Analyzer which uses your datalogged KAMRFs to calculate adjustments to your MAF curve.

 

[Stanger007]

I still have problems with a cold start, and the idle hanging when I come to a stop. I am hoping to figure most of these otu when I get the AF dialed in.

What are the symptoms of your cold start problem?

My question is, is the best way to dial the AF ratio the MAF table?

For closed loop, using EECAnalyzer is the easiest way. You drive around, feed it the log and it analyzes your KAMRF to see what the computer was doing and it makes adjustments to your MAF Tranfer.

Also after I dial this is what is the best way to dial in the spark tables.

Tuning the spark is done a couple of different ways. This has been covered a good deal in the eectuning.org site as well as in the FAQ here I believe. Also look in the manual that comes with the latest beta of the twEECer software, Mike gives some good hints for maximum N/A spark. Aluminum heads can usually take more timing without detonating than iron heads can.

The dyno is the ultimate tool for fine tuning spark.

You can find it here also: http://www.mustang-tech.org/wiki/images/2/21/Tweecer-Beta3-Getting-Started.pdf

What is the A/F I should shoot for? If going all performance?

I'd shoot for somewhere between 12.0-12.5.

Should I change the TB scalar, since I went from stock to 75mm TB?

Yes, the TB Airflow scalar as well as Neutral Idle Airflow function should be altered. EECAnalyzer will help you with the calculations here.

How do I turn adaptive learning off?

http://www.mustang-tech.org/wiki/94-95_Mustangs_Tuning_Adaptive_Strategy

Combo:
TFS H/C/I
Pro-m 80mm
24# injectors
3:73s
MAC shorties, prochamber,flowmasters
255gph pump

Sage2k's car is very similar - we started with J4J1 and made a few changes. He has the hanging idle problem as well and is going to get off his butt and run EECAnalyzer one day soon (hint, hint Sam ) to correct it.

Wes

 

[mackey]

What are the symptoms of your cold start problem?



For closed loop, using EECAnalyzer is the easiest way. You drive around, feed it the log and it analyzes your KAMRF to see what the computer was doing and it makes adjustments to your MAF Tranfer.


Tuning the spark is done a couple of different ways. This has been covered a good deal in the eectuning.org site as well as in the FAQ here I believe. Also look in the manual that comes with the latest beta of the twEECer software, Mike gives some good hints for maximum N/A spark. Aluminum heads can usually take more timing without detonating than iron heads can.

The dyno is the ultimate tool for fine tuning spark.

You can find it here also: http://www.mustang-tech.org/wiki/images/2/21/Tweecer-Beta3-Getting-Started.pdf


I'd shoot for somewhere between 12.0-12.5.


Yes, the TB Airflow scalar as well as Neutral Idle Airflow function should be altered. EECAnalyzer will help you with the calculations here.


http://www.mustang-tech.org/wiki/94-95_Mustangs_Tuning_Adaptive_Strategy


Sage2k's car is very similar - we started with J4J1 and made a few changes. He has the hanging idle problem as well and is going to get off his butt and run EECAnalyzer one day soon (hint, hint Sam ) to correct it.

Wes

Isn't tuning from the KARMF tuning from the stock narrowband? Wouldn't I rather use the wideband to get more accurate air:fuel

 

[Stanger007]

Isn't tuning from the KARMF tuning from the stock narrowband? Wouldn't I rather use the wideband to get more accurate air:fuel

The stock narrowbands are actually pretty good at sensing stoich. They are about worthless when it comes to determining any other air to fuel ratio, however.

I can confirm this for you - I'm in the middle of perfecting the MAF transfer for my new 90mm Lightning meter. The narrowband sensors are nearly dead on with what my LC-1 sees.

If you want to run open loop all the time then you can definitely go by solely what the wideband says. If you keep adaptive strategy enabled then the readings from the stock O2s will be constantly skewing your ratios.

Wes

 

[mackey]

The stock narrowbands are actually pretty good at sensing stoich. They are about worthless when it comes to determining any other air to fuel ratio, however.

I can confirm this for you - I'm in the middle of perfecting the MAF transfer for my new 90mm Lightning meter. The narrowband sensors are nearly dead on with what my LC-1 sees.

If you want to run open loop all the time then you can definitely go by solely what the wideband says. If you keep adaptive strategy enabled then the readings from the stock O2s will be constantly skewing your ratios.

Wes

How do I disable adaptive strategy? open loop is when the car starts correct?

Lets talk about a scenario.

My car is running at 15.5:1 Air:fuel (wideband) at idle while running for 30minutes. I want to bring it down to say 13:1 or even 12:1. To do this I would lean out the MAF transfer at the idle voltage, correct?

The adaptive strategy would not get in the way of this right?

 

[mackey]

How do I force the engine to stay in OL?

I've been reading all the manuals, and is there a way to trick the computer into keeping the car running at lets say 12.5:1 rather than trying to go to the stock 14.6:1. What is the table for this? I can't seem to find it. If I can do that I won't have to force open loop. I presume it would be better to stay in CL.

 

[Stanger007]

open loop is when the car starts correct?

You'll be in Open Loop and the Startup strategy (which adds fuel and slowly decreases it - see the "Fuel Table - Startup" to see how this plays in) when you first start the car as well as when you are at WOT.

Lets talk about a scenario.

My car is running at 15.5:1 Air:fuel (wideband) at idle while running for 30minutes. I want to bring it down to say 13:1 or even 12:1. To do this I would lean out the MAF transfer at the idle voltage, correct?

The adaptive strategy would not get in the way of this right?

First thing, because of my experience with the LC-1 and voltage offsets skewing the readings, I would question the 15.5:1 that you are idling at. What do the LAMBSE values say while you are idling, are they constantly below 14.5? How about your KAMRF's?

I bring this up because my LC-1 was slightly off because of a voltage drop by the time my twEECer got the signal. Once I corrected for the drop, my stock O2s and LC-1 read nearly identical to one another.

Second thing - I'm not sure why you would want to bring your AFR down that low at an idle, but the MAF is one place to do it. You'll also have to turn off adaptive learning and adjustment, as that will constantly be forcing you back to what the narrowbands see at 14.7.

If you want to change the OL fuel tables, that is the "Fuel Table - Stabilized Open Loop" table.

How do I disable adaptive strategy?

How do I force the engine to stay in OL?

This link has what you need: http://www.mustang-tech.org/wiki/94-95_Mustangs_Tuning_Adaptive_Strategy

Wes

 

[final5-0]

The topic in this thread seems to be jumping around a good bit and I may not be understanding your objectives correctly

Looks like to me .. If you are trying to obtain a good stable CL tune you would want to keep the adaptive in place and allow it to help your efforts

I don't understand why you would not wanna allow the pcm to use all its various inputs to effectively provide you with the best possible CL tune during ALL different driving conditions

As for the maf curve ... It would seem to me you could start with the info sheet provided with the meter or if you don't have it ... just use a generic curve which is gonna be fairly close anyway

I somehow or the other think you may be trying to mix tuning in Closed Loop with tuning in Open Loop

Again ... If I've misunderstood ... set me straight

Grady

 

[mackey]

Well my objective right now is to get the car dialed in A/F wise.

The point I'm trying to get at is, if I wanted to get the car down to a 12.5 A/F ratio across all RPMS, which would be the easiest way to do it.

Would it be to force OL and go from the wideband,

or

Stay in CL, and let the o2 sensors work it.

If I stay in CL, which values would I change to get the 12.5:1. Is it a table?
If I stay with forcing OL, wouldn't I just have to adjust the MAF transfer?

 

[final5-0]

Well my objective right now is to get the car dialed in A/F wise.

The point I'm trying to get at is, if I wanted to get the car down to a 12.5 A/F ratio across all RPMS, which would be the easiest way to do it.

Would it be to force OL and go from the wideband,

or

Stay in CL, and let the o2 sensors work it.

If I stay in CL, which values would I change to get the 12.5:1. Is it a table?
If I stay with forcing OL, wouldn't I just have to adjust the MAF transfer?

Thanks for clearing all that up for me

The whole reason for the CL tune is to allow you to stay at the optimum af ratio
of 14.7 to 1.00

I guess you could say ... it is called Closed Loop cause the O2's control everything
in a Closed Loop.

Now for the most part ... this is idle, cruise, and light load driving conditions.

The K E Y word in the above sentence is ... load :Word:

Its all about load
and
NOT so much about RPM ... when talking about a 94-95 pcm

You can use the KAMRF values to fine tune the adaptive so it has the ability to
stay in its 12.5% + or - Closed Loop range.

Y O U don't control the CL af ratio
The adaptive will do that for you

Now ... when talking about your WOT af ratio (Open Loop) ............

The O2's drop out cause the load ( there is that word again ) is high and you
use fuel tables & high end portion of the maf curve to control things.

See how those two things are radically different

Grady

 

[mackey]

Which fuel tables would I use to adjust WOT values?

 

[final5-0]

Which fuel tables would I use to adjust WOT values?

Well ... In my version it is called Open Loop Base Stabilized or something
close to that ... I'm not on my pc at this time and can't verify for you to
be sure.

Who knows what it is called in the newer software

You need to tread kinda carefully here :Word:

Watch the spark value and wide band so you don't go too lean

Once again ... If your Closed Loop tune is not established .......
You very well could be setting yourself up for double or triple work

btw ... the fuel table is just a part of the method here

I use that fuel table AND the Open Loop portion of the maf transfer curve
to arrive at my final WOT af ratio.

Grady

 

[Stanger007]

I think Grady and I use the same method to get at our WOT AFR.

I command an AFR in the "Fuel Table - Stabilized Open Loop" table and then "make it so" on the MAF Transfer according to my dialed in wideband.

Wes

 

[mackey]

So i see the table, I'm guessing the easiest way to get this right is to datalog a bit, and then adapt the tables based on my load percentage at different rpms to adjust my A/F Ratio. The easiest way to get the wideband is through the EGR, but what if I need to keep my EGR operational for smog?

 

[Stanger007]

I run a DataQ box that lets you pull in several different inputs. Good if you wanted to log, say boost and AFR and other things.

You can also just disable the EGR while you are doing WOT tuning. Grady has this setup.

Wes

 

[final5-0]

I took the pcm wire that receives input from the egr and hooked it on the center
pole of a switch. I then placed on the sides of the switch the wire from the egr
and the wire from the wb.

This allows me an either or kind of deal between the two devices

As for the af ratio

Have you spent any time on the wiki or my little site

I ask because the steps to dialing in your final WOT af ratio are laid out in detail
on both of those places.

We have talked about it from time to time on this site as well.

Having said that ... I'll give point out the basic tables and functions you will be
working with and you can get the details from one of those other places

table - fuel table stabilized OL
table - spark base table
function - maf transfer (open loop portion only)
function - fuel enrichment for high speed

There is just no way around it
One has to do the research
if
They are gonna be worth a hoot at self tuning :Word:

Here are a few tips
I've used to be the most effective at finding reliable info quickly

This site first

NAME - You know the names of Tweecer users here ... so use them
Greg-blksn955.o ... John-WhiteDevil ... Wes-Stanger007 ... are the ones
I can recall at this moment but there certainly are more

KEYWORDS - The more descriptive or specific ... The better

Example Search - You seek info on WOT af ratio

Using NAME of final5-0
and
KEYWORD of enrichment or stabilized
and
94-95 5.0 Tuning Forum ... Well ... There you have it ... Bingo
More than enough to get you started

Now ... Other Sites

You gotta be careful as you could be mislead by threads
where the talk is on Stangs before and after the years of 94-95. I suggest you
get to know the names of those members who have a 94-95 Stangs and focus in
on their info.

Lastly ... there are a few places where the info is even more focused to your
specific 94-95 Stang and the content is focused to tuning. The wiki and my little
place would be examples of that type.

Grady

 

[mackey]

Well I just got my wideband installed.

The car idles as normal, 14.5-15.6 AFR

WOT: the car is around 9.9 - 10.0 AFR

I was really suprised how much gas it was getting from the j4j1 with a pro-m 24 calibration. I'm guessing I'm leaving a good amount of power behind by pouring this much gas in and hopefully a few tenths at the track. Ran a 12.9 with this tune.

Final50 I started reading your site and bookmarked it. It's very useful.

Also my car goes very lean when I'm at like 3k and just letting the motor brake the car. Is this normal? I just read your info on the spike on acceleration quick, I'm wondering if it could be the same for letting the car speed down with just the motor.

 

[Methodical]

Well I just got my wideband installed.

The car idles as normal, 14.5-15.6 AFR

WOT: the car is around 9.9 - 10.0 AFR

I was really suprised how much gas it was getting from the j4j1 with a pro-m 24 calibration. I'm guessing I'm leaving a good amount of power behind by pouring this much gas in and hopefully a few tenths at the track. Ran a 12.9 with this tune.

Final50 I started reading your site and bookmarked it. It's very useful.

Also my car goes very lean when I'm at like 3k and just letting the motor brake the car. Is this normal? I just read your info on the spike on acceleration quick, I'm wondering if it could be the same for letting the car speed down with just the motor.

Yes going lean when decelarating is normal as fuel is cutoff. I see 20:1 AFR when letting off the gas.

 

[mackey]

Yes going lean when decelarating is normal as fuel is cutoff. I see 20:1 AFR when letting off the gas.

Ok, thanks!