OK guys,

some of you may have seen my post about the main spark table with relation to the base timing. I am totally shocked NOW!

I aquired the $1f definition from tunercat to help a friend out with his setup. We were looking at GMEPRO and were not sure if the base timing was already added in the shown value or not. We did clear this up with Terry's verification that it was NOT included.

So then I get Tunercat and again they verify that their definition does NOT include it. So just for the heck of it I send them an email asking if the $6e table contains the base timing, which from everything I read here, says that it is. Here is their exact reply:
[quote]
Hi Jesse,

No, the base timing is not included in the $6E main spark table either. As a rule we don't include the base timing values in any of the main spark tables. Some calibrations do have a spark bias value that is associated with the main spark table. In these calibrations, the bias value is included in the main spark table but neither the $1F or the $6E have a main spark bias value.



Best Regards,

TC[/qoute]

So what the hell gives here...for the past year I have assumed that the base timing was included in the $6e so I have my timing at 6* base and shown value in the table of 32*+6* of WOT adv. so I am running 44* of total timing

It seems like Every time I talk to someone else they give me a different story.

Someone re-explain this to me before I have a nervous breakdown

 

Ok, I just looked through the '7747 and find that there is a value for Initial Spark Advance, Spark Bias Warm, and Spark Bias Cold. In the .bin I was looking at ARHT (5.7L w/ Manual), the Initial is zeroed out, the Warm Bias is set at 9* and the Cold Bias is set at 20*. If the bias is part of the main spark table as indicated in the email above, how can there be two values for the Bias?.... now I'm all confused.

 

Well Dude I am not making it up...just trying to sport the mess out myself. Something as basic as this is turning into a cluster buck.

everything I have read indicates that the $6e is including the base timing for instance:

Base timing = 6*
Main Spark Table = 32*
WOT SA = 6*

Option1:
To find total timing would be: 6*base + 26* (what the ESC is adding) + 6* WOT = 38* total timing.

The way TC is saying it makes me believe that its:

Option2:
base 6* + Main 32* + 6* WOT = 44* total

You guys tell me what is right and wrong...because I am freakin stumped after 2 years of tuning....

 

It just wants to know your base timing so it can stop total advance after 42*(or whatever value you may have changed it too) in case you added to much timing you don't hurt something.

 

this is not surprising to anyone?

 

Does it matter what the number is ?

You should be tuning for what the car wants NOT what you expect to see !

As long as adding 1 deg of timing equates to 1 extra degree thats all that matters - every engine responds differently to timing and most take a huge dive aftyer max torque and slowly return , time to get back to tuning to the engine.:lala:

 

ski,

Don't fret. As mentioned in my previous post - the $6E for WinBin, TC, and GMEPro are the SAME with regard to total timing. If you specify 36d in the SA table for max LV8 then 36d will be the max timing (assuming no knock and no other +/-) for that LV8/RPM.

You are misinterpreting what TC said. What he is saying is that no extra additions/subtractions to the SA table are necessary. What you specify is what you get. Period.

"neither the $1F or the $6E have a main spark bias value"
"No, the base timing is not included in the $6E main spark table "

This means that he doesn't add or subtract anything with regard to the SA table. So, when you specify 36d in the table then that will be your max timing. The ECM calculated 'on-the-fly' the amount of timing needed to reach that 36d via doing all the additions and subtractions for you. It subtracts the base timing from the value you specified in the SA table in order to figure out exactly how much spark needs to be added in order to reach that value you specified.

See?

Tim

 

Tim,

Thanks for your reply. That is the way I have always thought about this. However with the $1f, my friend checked his and the base timing was not added in. When he would disconnect the ESC the timing would return to 1* (where he had it set, its a 12:1 engine and he was getting pinging).

Then when he would plug it in. The timing would increase the amount shown in the table...plus the base timing. So that says to me that the base timing is NOT included. I agree and its what I always assumed with the $6e that the timing was increased to the tables desired value.

Can you help us straighten out the $1f now? The way tunercat made it sound is that the $1f and $6e should be the same. From what Corky provided for a test is not saying that.

Thanks..I appreciate your time with this...

Jesse

 

Quote; It just wants to know your base timing so it can stop total advance after 42*(or whatever value you may have changed it too) in case you added to much timing you don't hurt something.
Are you referring to the table in constant that ask your initial timing?If so,I'm like you I thought it asked ,then I/we came to the conclusion that it needs to know so that it will only put that value in that particular load/cell only with the exception as noted being
timing for wot,temperature changes, and rpm.I guess it's back to the drawing board for a lot of us.

 

I am with Tomcat on this one. not that I would not like to know what is going on, but when push comes to shove, I relly couldn't give a rip. if I give it more timing & it makes more HP, I am good. if I give it more timing & it starts to ping, I am going the Wrong way.

Give it just enough to make Max HP, not as much as you can get away with w/o detonation, there is a fine line on this one.

BW

 

Ok, Ok, Ok fellas after EXTENSIVE conversations with Tunercat here is the final answer.

The timing of initial spark is in fact included into the $1f and $6e tables. So that if you put 32* of total timing, keep in mind this is assuming that no other conditions for spark adders or subtractors are met, that the ESC will add 26* for a total of 32* if base timing is at 6*. END OF STORY and confusion for me.

As for the statements about "who cares" give the car what it wants, well I for one would like to know how the values are being interpreted into the tune of my car. I don't know how much cash you have invested into your engine, but I know I have more than enough to want to know, before I go blindly into the unknown.

As for the cap idea, I don't buy that for the simple fact that the computer has no *real* way to know EXACTLY how much timing the engine really has. For instance if I enter the base timing at 6* and then manually turn the distributer to give myself 15* base timing..there is no way in hell that computer knows I bumped the timing up and additional 9*. If everything is set up to the parameters entered then yes I agree, but for someone unknowly reading what you posted would think that you could never get more than 42* of advancement.

I would like to thank all that contributed to the sorting of this out. Its amazing how confusing something that you *thought* you knew could get twisted around.

Cheers!

 

Ski,
Glad you got that sorted out.

Now, does anybody know if the $42 tables are handled the same way? The Initial Advance and Warm & Cold Bias values are confusing me. Thanks...

 

Not real familiar with that def. But what he said is EVERY one that has come from Tunercat, WINbin, and GMEPRO has the initial contained in the main spark table. This was also verified by Terry, GMEPRO, that all his do also. Which only really makes sense.

Cheers.

 

Hey man, wha choo doin hangin round here! I'm late to this thread, but as I was reading, I'm thinking "no way tunercat doesn't include base timing". Glad to hear you got it cleared.

Regarding "give it what it wants", now THAT can get dangerous. I used to tune that way (throw theory and hear-say aside), and only realized after I got my WBO2 meter that I was running dangerously lean at WOT. The car LOVED IT, best ETs! I quickly retuned to 12.8:1. Car slowed down, but should last to race another day.

There is validity to the old saying I learned WAAAAAAAY back in jr. high school "they always run best just before they BLOW UP!"

see ya,

-Bill (ELEVENS)

 

ski/Trax,

I have a 7747 on my TBI and use TC. Unless I have had it wrong, the base timing is NOT in the Main Spark Table. MSB is however. When I change the Constant Table for MSB, the Main Spark Table will change to reflect the MSB setting. That doesn't happen with the initial. Again this is for the $42 ECM. Did the person from TC say ALL $ were done the same way?
If what he's saying is true, then I'm running 28d total at WOT! Got a ways to go then. Thanks for bringing this up.

 

That is what he said. They have NEVER put out a defination that did not include base in the main map. You may want to touch base to make sure with your TBI setup,

 

Well I have both Tunercat and GMEPro. This is what I see on my versions.

$8D Tunercat (base timing is not included in main spark maps)
$8D GMEPro (base timing of 6 degrees fixed IS included in maps)

$6E Tunercat (base timing of 6 degrees fixed is included in map)
$6E GMEPro (base timing of 6 degrees fixed is included in map)

$1F Tunercat (base timing of 6 degrees fixed is included in map)
$1F GMEPro (base timing of 6 degrees fixed is included in map)


I have verified this with Diacom on my car. If you change the reference in the chip from 6 to 10, the spark advance numbers of course stay the same but the values displayed in Diacom will be 10 degrees off instead of 6 degrees (rel to TDC vs rel to ref).

I have always added in my head 6 degrees of timing to the tables that tunercat displays when modifying my $8D chip. Again, the values in TC vs GMEpro are always different by 6 degrees when using the $8D code. In $6E and $1F they are the same. This is why I always strongly recommend setting the base timing to 6 degrees and never change it.

So where are we off here?

Jason

 

Jase,

I don't believe its included in the $42def either and you have proven that its not in EVERY definition TC has put out. I am running 10d Initial and there's no way the motor would run as strong as it does, get the mpg it does with 25d of total advance + a few d in PE for WOT. Again, I would sure like to know definitively and will try to call TC tomorrow.

 

They all include the base timing. Trust me.

I went through this for a week straight! Some confuse people because the main table has a low value, that makes it look like it doesn't, but when you look at all the other spark adders. It does.

TC will verify for you if you like.

 

89 Vette - you need to update your $8D file. It is now included.

Tim

 

Ski, they DON'T all have it so now I can't trust you sorry. I know what I am seeing. In my $8D tdf it's not there. Traxion confirmed that the new def's its there. Trax, do you remember when it was not? Dom, you better go over that carefully with TC when you call. This is a dangerous thing here with what appears are out dated tdf files. I wonder how many people out there have 6 degrees more timing than they think and are not paying attention to their scanners?

Ski, what TC may have meant was they never issued a $6E or $1F tdf without it included. Weren't the $42 and the $8D the first two tdf's that TC came out with?

 

Guys,

I can tell you the $42def I have is of 2 weeks ago when I last downloaded it. My spark counts are minimal maybe suggesting ski is correct. But throttle response is excellent. And the TFS heads on my motor have been shown to respond well with a TA of 38d. Thats where I have mine and I specifically did dyno runs measuring peak hp and torque with the variable being TA. I tried increments of 2d starting with what I thought was 32d. TA of 38d at 3600rpm worked out best. But that was using 25d in Main Spark Table and 10d initial with remainder in PE.

 

$8D Tunercat (base timing is not included in main spark maps)
$8D GMEPro (base timing of 6 degrees fixed IS included in maps)

Dom, I can't speak of your tables because I do not have the .tdf.

Again look at the above differences in my $8D files. If I look at the spark advance values in GMEpro they are are ALL 6 degrees higher than the values displayed in TC. I would advise everyone (especially me) to update their tdf's.

 

Guys,

Here's what TC's help manual says,
"Main Spark Advance Vs RPM Vs Load
The Main Spark Advance table is a function of manifold pressure and RPM. This table is in use at conditions other than idle as defined by throttle position, RPM, vehicle speed and MAP"
In other tables it discusses how that advance is either subtracted or added to main table, ie the Main Spark Bias.
Again, I am not suggesting this is happening to all def files but I'd like to clear up the one I am using, the $42 for the 7747.

 

Using WinBin to look at the $42, the Main Spark table is titled "Spark Advance (sub Warm Bias). Not really sure how to interpret this. Would it mean that the Warm Bias has already been subtracted or you need to subtract the Warm Bias from the values shown.

 

Guys...Here is what I did to clear up the discussion with TC...I gave his some examples so there was no confusing teminology..

Option 1

Assume:
ref spark 6*
*main* table timing value 36*

total timing =36* (this means the ECM is really only adding 30*, although it shows 36*)

Option 2

Assume: same

ref spark 6*
*main table timing value 36*

Total timing=42*

He said it has always been option 1 in every defination they EVER put out. I can only convey what he said. I think what is getting some of us, as I stated before, if that newer defininitions may have other spark adders or subtractors that the earlier versions did not include. For example sake a highway mode SA. This might be why you are seeing lower values in the new version..Just a thought. But I am gonna assume that the ref is always included.

Furthermore, I know that I read about a year ago, that people were saying the $6e has the base included, and I agree, so did TC. However, the same people were saying that the $8d did not have the base. I disagree with this and so did TC. He said they NEVER did not include the base timing in the main table. So what you see in that table is the TOTAL advance (unless you have spark adders or subtractors). HE SAID VERY BRUNTLY: you NEVER have to add the base timing in, never did, never will.

This is a very good discussion...wish TC would frequent the boards so he could give his input.

 

One other thing...its easy to see what I am saying with a timing light....

If you unplug your ESC you will get your base timing of 6*. When you plug it in, you will get, let just say 25*. At that given RPM and LV8 the table value is 25*.

So the ECM is really only adding 19*, not a full 25*.

Its getting 25* from 6* base and then 19* ESC added.

otherwise if it was not adding the base timing you would be getting 31* timing under those same conditions. Try for yourself you will see what I am talking about.

Later!

 

IM with 89vette, I must have an old version of the$8D tunercat file. If IM showing 20* in the main table with 6* initial. I have 26* of total timing showing on my scanner.

 

Guys,

I guess I can't believe it but I checked my latest bin file using WinBin and the SA tables in both editors. They are THE SAME. I changed the Initial in WinBin and the SA table stayed the same just as it does in TC. Is that because the bin is still commanding that "X" total advance and so now the ECM will increase the additional advance to make up for the lowered initial? Or is it because both editors expect you to combine up the various "spark adders" in your head?

 

Hi All,
I am another to agree with 89vette. I also use both Gmepro and TC.

One reason I stick with gmepro for primary tuning . I was just using TC for fuel map (3d view) for adjustments.

If I do use TC for timing adjustments I goto the ECM CONSTANTS and adjust the base timing to ZERO. then load up you timing map . Now you will see you full timing. If you have some PE timing adder you will have to add this also. When I am done teaking I go back to ECM constants and set my base back to 6.

I am running a older version of 8d for TC. fall 2001.

Dennis

 

If you change the base timing reference with the software, it will not change the values displayed in the SA tables. The 6 degrees is a fixed amount. Tunercat told me that I needed to update my $8D tdf so that the value displayed in my table is the total timing from TDC and not from the ref. He sent me an update and now its included. I think TC is a great program but it seems that the wrong information is coming from him when he tells one person he never didn't include it but tells me that the old version does not have it. So we are all right! My suggesion again is for everyone to use the latest versions.

Jason

 

Anybody got the phone number for TC? Can't find ity anywhere.

 

Guys,


I checked my timing at idle. My crank is set at 10d and the Main Table shows 18d at 800-1200rpm and at 40-50kPa. When I put the timing light on it, it showed 26-27d timing. Cold Spark Bias is about -2d. The $42 def file hasn't been updated since 2001 based on the information on the TC website. Based on that, I'd say that, at least for the 7747, the Main Table still DOES NOT include the crank degrees. That's consistent with the rest of my experience in tuning for WOT.

 

Gentlemen,

I spoke to John Howie this morning. From the "horse's mouth"
"The crank timing is NOT INCLUDED in the Main Spark Table values for ANY of the def files. There was a mistake in the $8d file initially where it had been included but that has now been changed". So the SA table only shows the INCREMENTAL amount of timing to be added to the crank timing. The initial advance in the ECM Constant Table must be used somewhere else but its not being added to the SA. You need to do that in your head. So if you're trying to come up with the timing at WOT, its necessary to be aware of initial timing, plus the SA table value, plus the PE adder value for TOTAL TIMING at WOT. And from what John said, all the def files are like this. Hope this puts the issue to rest for everyone.

 

I am locking this thread to try to prevent confusion.

The timing specified in the SA table will be your total timing specified for that RPM vs kPa (or LV8). Period. Whatever you put in those table cells is what the ECM will try to achieve. There is no need to do any additions, subtractions, etc. If you specify 38 degrees at 3600rpms at 50kPa then the total timing will be 38 degrees (as long as you don't get any knock, there is no Octane retard in effect, there are no PE adders, and you are not in highway mode). Basically, the ECM will add whatever timing is necessary in order to achieve the max that you specified in that cell. As indicated in the previous post and in many posts before that post ... it was the old version of TunerCat's $8D file that handled this differently. Everybody make sure that you are running the latest versions.

Tim