94-95 Spark Tables Inside

[final5-0]

I've been working with some of the guys over at the Corral with various pcm topics. I put together an image of the Base Spark Tables for all of our cars (Cobra R not included) for them and I thought some of you guys over here who have not had the opportunity to see stuff like this might like to take a peek also.

The thing that motivated me to put this up was the typical PING THREAD that you see come up about every week on this site and over at the Corral as welll.

For some time now I've made mention about there being differences in the Spark Tables between the GT & the Cobra.

Now everybody can see for themselves.

j4j1 is the Cobra

t4m0 is the stick trans GT

For those of you who have auto trans Stangs, your u4p0 & w4h0 pcm's use the same table as the GT.

Maybe this will give some an idea of why the GT's ping from day one no matter what you do to try and fix it, lol.

Another thing the GT has that makes it more prone to ping than the Cobra is it's fuel table is leaner.

A mention to those who have not seen this kind of stuff...........................
You most likely have heard about our pcm's being load based.....................
Take a look at the left side of the table.............and what do you see, lol

If anybody has Q's or comments about these tables feel free to start a discussion.

Later
Grady

 

[wytstang]

What does the load #'s mean (0.8/0.7/0.6/ect {volts maybe})??

 

[WhiteDevil]

Good post man. Just so everyone knows .9 load is WOT the lowest Load is like coasting. THe lower area is idle and then the mid range is part throttle.

 

[blksn955.o]

Great comparo, Grady Toss up screen shot of a comparo of the j4j1, and T4M0 fuel tables and see how rich these things run from the factory.

I noticed also that when I finaly got the fan controles working with the cooler 190* t-stat that the pinging went away and I am able to run more timing in the higher load areas. This is with the egr still hooked up and turned on and an A/F commanded of 13.1-13.2 timing at 32* in high load on the j4j1. I ran a real quick gt tune (realy base just to see if it pinged) with the fan setting for the 190 and an added 5* across the board with no pinging with 87.

Idle is like .1 to .2 (I see like .15-.17 or so if I recall in my datalogs).

 

[final5-0]

What does the load #'s mean (0.8/0.7/0.6/ect {volts maybe})??

Danny

Just like John said!

The top load row is the greatest
The bottom row is the least

I'll give you some different kinds of driving conditions that may help make things more clear.

1) At idle I show a load of about 25%

2) WOT in 3rd gear@6200 rpm I show a load of about 123%

3) On the highway in 5th gear I went from a steady cruise to a very gentle increase in speed of about 55mph to 60mph with a tps voltage of 1.35volts to 1.45volts and the load range was about 30% to 40%.

Hope that kinda sorta gives you an idea of how the load thing comes into play as they say

Later
Grady

 

[HISSIN50]

Great stuff Grady. I saw your post on Danny's thread on the other board.

 

[final5-0]

Great stuff Grady. I saw your post on Danny's thread on the other board.

You just can't stand it ....................... can you?

Sooner or later .........................

We're gonna win you over to the self tuning camp!

Later
Grady

 

[94GTLaserRC]

Im with this function on the TwEECer, but Im subscribing for future reference.

Thanks Grady!!

RC

 

[mo_dingo]

At 5k at low load, it said 40*. Does that mean 40* advance not including the dizzy's timing of 10*? That is absolutely nuts....
Scott

 

[HISSIN50]

Scott, you dont want to know how much advance I have (extrapolating timing marks on balancers is not something I like doing).

Grady, someday someday. In the meantime, I will keep lookin for a place to stick some bigger jets.

 

[WhiteDevil]

At 5k at low load, it said 40*. Does that mean 40* advance not including the dizzy's timing of 10*? That is absolutely nuts....
Scott

Right, its only 40 not 40 plus 10. All the numbers are based on the assumtion the base timing is a 10. So when you advance it then you fool the comp, when you put your timing at 13 degrees you at +3 to that WHOLE table. You probably wouldnt be at 5k at a low load though, only if you hammered it and then let off.

 

[final5-0]

At 5k at low load, it said 40*. Does that mean 40* advance not including the dizzy's timing of 10*? That is absolutely nuts....
Scott

You bring up a good point I forgot to mention.

All of the values are as they appear ONLY if you have your dizzy set at the factory value of 10*.

If your not at 10*, you would need to + or - by that set amount.

These values might be a little more or a little less due to ect, act, and stuff like that.

For the most part, these tables give you an idea of what is goin on with the spark in your Stang's pcm.

Later
Grady

 

[Rootus]

Argh! Grady! You're supposed to keep this stuff secret!!! How can we be 3l33t if everyone knows how it works??

Dave

 

[HISSIN50]

Argh! Grady! You're supposed to keep this stuff secret!!! How can we be 3l33t if everyone knows how it works??

Dave

Dave, I dont think you have to worry. I have no idea what 3l33t is. (The best I could do is figure it is an alpha-numeric phoenetic for 'Elite').

 

[94GTLaserRC]

Argh! Grady! You're supposed to keep this stuff secret!!! How can we be 3l33t if everyone knows how it works??

Dave

I just put this thread on my entire office Email list !!
RC

 

[bayellowstang]

Hey Grady, How about a shot of the tables your running?

Have you played with the load scaling at all. I have my load set to follow the factory graph in EEC analyzer and it made a huge difference in how it runs.


And I'm with Rootus!!! LOL

 

[wytstang]

Thanks for adding to my confusion Grady/John j/k I understand now [Ace Ventura Voice on] I have excercised the demon[/Ace Ventura voice off]

 

[final5-0]

Hey Grady, How about a shot of the tables your running?

Have you played with the load scaling at all. I have my load set to follow the factory graph in EEC analyzer and it made a huge difference in how it runs.


And I'm with Rootus!!! LOL

Steve

Its no seceret really but I'm not gonna go the trouble to copy, paste, host, and bla, bla, bla, all that stuff again, lol.

I just had the total amount of spark I wanted in by 2500 and you can use the top or top two load rows for your WOT conditions.

I've thought about playing with the ls but when I talk to peeps with mild na combos like mine, some say it did not make much if any difference.

Later
Grady

 

[final5-0]

Great comparo, Grady Toss up screen shot of a comparo of the j4j1, and T4M0 fuel tables and see how rich these things run from the factory.

Thats a great idea Greg........why don't you do that?

I noticed also that when I finaly got the fan controles working with the cooler 190* t-stat that the pinging went away and I am able to run more timing in the higher load areas. This is with the egr still hooked up and turned on and an A/F commanded of 13.1-13.2 timing at 32* in high load on the j4j1. I ran a real quick gt tune (realy base just to see if it pinged) with the fan setting for the 190 and an added 5* across the board with no pinging with 87.

Idle is like .1 to .2 (I see like .15-.17 or so if I recall in my datalogs).

No ping with 87 ...... way to go

looks like your getting stuff dialed in pretty good

Later
Grady

 

[WhiteDevil]

Steve

I've thought about playing with the ls but when I talk to peeps with mild na combos like mine, some say it did not make much if any difference.

Later
Grady

Yeah i played with min using EEC analyzer. It brought my idle load down, and my wot load down. Didnt change much as for driveablity, the only thing i noticed was the my RPMs didnt seem to hang as much when coming to a stop, but it was only a very slight difference.