What should be my first tweecer mod?

[DoctorB712]

What should I change first. I would like to start with only one thing (not the fan or egr stuff).

Thanks

Sig for info on my car

 

[Zero Signal]

Enter your true MAF transfer curve from the flow sheet and make sure your injector slopes correspond with your injectors My moto: Driveability FIRST!

 

[DoctorB712]

There are some curves already stored in the program. I have a PMAS (new prom) for 24. Should I use that or make one with the calibration sheet?

second, how do I change the injector slope? Scalar or table. Details would be good at to what exactly I would ned to do.

Thanks

 

[final5-0]

There are some curves already stored in the program. I have a PMAS (new prom) for 24. Should I use that or make one with the calibration sheet?

http://forums.stangnet.com/showthread.php?t=623370

second, how do I change the injector slope? Scalar or table. Details would be good at to what exactly I would ned to do.

Thanks

I'd move to the j4j1 cal file

Works better with mods

Has all the 24lb inj values already setup for you

Like Mr. Jonn said above

Driveability FIRST!

Grady

 

[DoctorB712]

Concerning the J4J1 file. The injectors are already set at 24. There must be other differences between the cobra and normal GT file? Spark, fuel tables... etc?

What are some of the major differences?

 

[Zero Signal]

I don't know . . . . before my heads and cam, I tried running the J4J1 and with the stock longblock, it's kind of a pain to get the car to run right. After the heads and cam it was great to work with.

For the MAF curve, you really want accuracy. I would enter in the flow sheet that you got with your MAF you lazy bum!

 

[final5-0]

Concerning the J4J1 file. The injectors are already set at 24. There must be other differences between the cobra and normal GT file? Spark, fuel tables... etc?

What are some of the major differences?

Since you are just getting started, I'll not go into detail and just list some of the things that I believe make a real noticable difference in CL operation which makes the Cobra file so much better for drivability with a combo that has h/c/i, maf, larger inj, and so on.

load scalar
inj slopes
inj offsets
inj breakpoint
various air flow values at idle conditions
not as many spark & fuel adders

As for OL or WOT operation

The fuel tables are fatter and the spark tables are softer. This will mean if one is stock or close to stock and loads up the Cobra file ... they will feel a loss of power. This is easily fixed with a bit more spark btw.

The combo as you see it in my sig would not idle worth a dam, burn your eyes at idle big time from over rich fuel raio, surge and buck at cruise, and in general ... had massive drivability issues with the t4m0 file This kinda stuff was even happening with me using the stock maf which has a curve that is a 100% known fact.

anyway

I worked for about a week on the t4m0 file with not a lot of success.

I loaded nothing but inj slopes & offsets in an unmodified j4j1 file and did a quick upload to the pcm and took a drive.

About 85% of my drivability gremlins were gone

Many peeps with similar combos have experienced the same as well

To be fair here, my tuning knowledge was not all that much in those days and these days, I most likely could tweec the t4m0 to my satisfaction
BUT
That is not the important thing here

IMHO, This is one of those rare times that the easy way out can be the best way to get the job done

Grady

 

[DoctorB712]

>The fuel tables are fatter and the spark tables are softer. This will mean if >one is stock or close to stock and loads up the Cobra file ... they will feel a >loss of power. This is easily fixed with a bit more spark btw.

What do you mean by "a bit more spark". I am mostly stock for now and would like to fix that loss of power with the cobra file. So is it a table, scalar function I need to change? How much do you change it by?

 

[blksn955.o]

the best way to do the timing will be in the spark tables.

you will need to kill a few tables by putting 55's in all cells, in the MBT and boarderline, while making the Alt. and base match each other. I wanna say thats it but I dont have my tweecer or notes here at work with me.

for perf. on the WOT side of things work with the top 2-3 rows of spark values and have say all your spark in by like 2,500-3k rpm...like you want 29-30-ish total spark to reach that level at the 2,500-3k area.

 

[DoctorB712]

What if I use the spark tables from the T4M0 and put them in the cobra file? Would that work?

Just thinking of different options.

 

[blksn955.o]

realy for perf. both the t4m0 and j4j1 are preaty lame for spark and both could use a bit of adj.

 

[DoctorB712]

I looked at the tables and there is 3 spark base:

spark_base_add_af_rat
spark_base_ECT_mult
spark_base_table

and 2 for MBT

MBT_table and MBT_ECT

Do I need to change all of them or do I focus on one?

p.s. Anybody have the T4M0 file? My car is in storage until next week. I am playing around with the software to get use to it and would like to upload the T4M0 file to see!

 

[blksn955.o]

the table that is labled "base" or that has no other defs. (as I call them that denote a more detailed functions) but is simple are the "master" tables, like the MBT_table, the others are "sub" tables, if you dissable the MBT master it takes out all other sub tables.

 

[DoctorB712]

I noticed that most of the sub tables in the J4J1 files are set at 0 while in the Gt file they are not. What are the benefits of disabling theses "sub" tables? Is it good not to have them and if so why did ford put them in?

p.s. I feel the more I am reading the more confused I get However I guess its part of the learning curve!!!!

 

[final5-0]

Here is a little tip that has always served me well when dealing with all that EEC stuff

Until you know what it is
and
How it works

Don't Hose Around With IT

Grady

 

[DoctorB712]

Why is the Y axis of the base spark table different on the GT vs cobra file? On the cobra file there is no 0.9 load and there is a 0.05 and on the GT there is a 0.9 load and no 0.05?

Thanks

 

[final5-0]

Why is the Y axis of the base spark table different on the GT vs cobra file? On the cobra file there is no 0.9 load and there is a 0.05 and on the GT there is a 0.9 load and no 0.05?

Thanks

There are quite a few subtle differences like this.

Some I understand and others I don't

By the time you reach a load of .8 ... having one more row is not gonna make much diff.

Having a row as small as .05 seems kinda useless but maybe you can obtain it during decell.

IMHO, I would not plug in stuff from the t4m0 as some of those subtle changes make up the advantange the j4j1 has in drivability.

Below is a copy & paste of general spark info from my site that may give you some ideas.

The question of why I don't get the spark values I call for comes up a lot. The final spark value can be effected by lots of things in a + or - way. Scalars can + or - the value but usually, you have to be at an extreme such as very high ECT's for an example.

There are four main Spark Tables and they are Base, Altitude, MBT, & BDLN (borderline). They all work together and can effect the final spark value by a + or - amount. To explain how they work is beyond this effort but very good write ups can be found on the various tuner sites if you wish to research.

My method for stable spark values by Spark Table manipulation.

Kill the Altitude, BDLN, & MBT Tables by using the value of 55 in all cells.
Use only the Base Table for tuning.

For the final values in the Base Table you will have to play with them a bit to see what your combo likes as each one can be different. I know I have to back down the spark a bit for hot Texas summers or I can hear a slight amount of ping.

Here is a rule of thumb for best WOT performance.
This is for na NOT forced induction combos.

Have all spark in by 2000 to 2500 rpm and a total amount in the range of 32 to 38.

You will be at max load for wot conditions and most peeps use the highest 1 or 2 load rows for WOT Tuning tweecing. I use the top two load rows myself.

Before we go any farther

*** CAUTION ***

Just as we dialed the spark back a bit for safety when tuning for fuel you wanna ensure your NOT lean when working with WOT spark tuning. DO NOT set your value to say 36 to 38 and let it rip with a WOT blast. If you don't have a wide band then you are not really sure where your final fuel ratio is so you are even more at risk for motor damage.

An old drag racers trick is to bump the total value up a couple of degrees at a time while all the time having a keen ear to hear ping. After the slightest amount of ping is heard the value is usually dropped back by a couple of degrees.

Remember my mantra for safety!

BIG FUEL ...... little spark

My Base Spark Table top two load row values are below.

500 700 900 1100 1300 1500 2000 2500 3000 4000 5000
10 12 14 18 22 26 32 34 34 34 34

The Scalar Spark_Adder_Global should be a value of 0
If you are gonna use this scalar to tune you might as well use the mechanical method of twisting the dizzy for spark tuning which gives no flexability at all.

DIZZY SETTING ...... stock setting of 10 and never change it again.

Killing the Shift Retard

We talked about this eariler but briefly, the Scalar spark_min_for_tip-in_retard value needs to match your total amount of advance in your Base Spark Table which will cause no retard when you tip in the throttle to WOT.

Since you got iron heads Matt, you may wanna start off kinda easy with something like a total value of 30@3K. You can then slowly juice it up a little bit at a time. Iron heads are more prone to the ping thing don't ya know.

Hope that helps Matt

Grady

 

[DoctorB712]

I'm not sure if I underdstand the shift retard? Mine is set at 5 now in the scalar. How can 1 value match a table of value?

My timing is set at 10, spark adder global=0.

Thabks again. I am focusing only on spark for now... fuel stuff later when I get wideband.

 

[final5-0]

I'm not sure if I underdstand the shift retard? Mine is set at 5 now in the scalar. How can 1 value match a table of value?

OK Mr. Noob

Just said that to give you an idea of how you can use dlogs to see it in action.

I've laid out step by step details for testing the tip in retard several times here and on the Corral. You will be blown away by how it really works.

Search it up and you will see it in your dlogs ... in all its Glory
and
You won't even have to shift

Its kinda cool & you'll have some fun

btw, gimme some feedback after you perform your little test run and envoke the big fix

Grady

 

[DoctorB712]

I will let you know next weekend... i't finally coming out of storage... if we dont get snow

If I understand your min_for_tip-in_retard is 34 Right!

Thanks for all the advice.