Tuning Research Questions

[jmbusch90]

Good afternoon,

Jumping to the point, this is a totally new tune. Ported heads, new cam, bored LS 6.0 so the original tune is dubbed no good. Furthermore, I haven't even attempted to start the vehicle, I'm conducting my research first before I turn her over.


Been doing my homework so I can get this thing started. I started watched Chopper Docs YouTube videos (awesome by the way great job) and have been reading the Read me segment via the homepage.

I came across https://forum.hptuners.com/showthrea...+timing+tuning and decided I better reevaluate my baseline tune file to now compensate for the cam.

On the spec sheet there's an advertised overlap(50.2 deg) and a overlap @0.050 (-1 deg), the link is below.

https://www.enginekits.com/camshafts...dr-121624.html

Which one does needs to be use?

Question?
For spark advance and retard table in VCM Scanner, what are the X & Y axis suppose to be? I noticed that on Chopper Docs video he had RPM vs cylinder mass.
Reason I ask is because the default is RPM vs kPA.

Another Question?
I haven't really found a good concrete answer from my searches but most tuning starts by adjusting the tables to get the engine started. I get that, but what are some red flags to look for the instant the engine starts where one would consider to shut the engine off and make adjustments asap? IE spark, surging (min/max rpm swings), etc
Again if this has already been answered in detail and I didn't find the thread, gimme the link and I'll go read up on it.

Oh and one more question....
What does an open loop tune consist of? By that I mean whats enabled and whats disabled?
If there's a thread that's already open on that, point me to it and ill read up on it.

Best Regards,

double

[cobaltssoverbooster]

Good afternoon,

Jumping to the point, this is a totally new tune. Ported heads, new cam, bored LS 6.0 so the original tune is dubbed no good. Furthermore, I haven't even attempted to start the vehicle, I'm conducting my research first before I turn her over.


Been doing my homework so I can get this thing started. I started watched Chopper Docs YouTube videos (awesome by the way great job) and have been reading the Read me segment via the homepage.

I came across https://forum.hptuners.com/showthrea...+timing+tuning and decided I better reevaluate my baseline tune file to now compensate for the cam.

On the spec sheet there's an advertised overlap(50.2 deg) and a overlap @0.050 (-1 deg), the link is below.

https://www.enginekits.com/camshafts...dr-121624.html

Which one does needs to be use?

Question?
For spark advance and retard table in VCM Scanner, what are the X & Y axis suppose to be? I noticed that on Chopper Docs video he had RPM vs cylinder mass.
Reason I ask is because the default is RPM vs kPA. The only thing you can do to the axis is change the units but you will only be allowed to change units of similar meaning. So you can change from kpa to psi to vac, but you can not change it to say temp *F or C.

Another Question?
I haven't really found a good concrete answer from my searches but most tuning starts by adjusting the tables to get the engine started. I get that, but what are some red flags to look for the instant the engine starts where one would consider to shut the engine off and make adjustments asap? IE spark, surging (min/max rpm swings), etc
Again if this has already been answered in detail and I didn't find the thread, gimme the link and I'll go read up on it.
stumbling, higher than expected idle, heavy rpm oscillation, afr readings beyond the extremes (less than 10.5 and higher than 17 on pump gas), irregular sensor value readings
Oh and one more question....
What does an open loop tune consist of? By that I mean whats enabled and whats disabled?No feedback sensor inputs are actively monitored. Therefore you wont be actively using the O2 sensors. This is typically associated with wideband setup threads because the O2 feedback interferes with the wideband use.
If there's a thread that's already open on that, point me to it and ill read up on it.

Best Regards,

double

[jmbusch90]

Question?
For spark advance and retard table in VCM Scanner, what are the X & Y axis suppose to be? I noticed that on Chopper Docs video he had RPM vs cylinder mass.
Reason I ask is because the default is RPM vs kPA. The only thing you can do to the axis is change the units but you will only be allowed to change units of similar meaning. So you can change from kpa to psi to vac, but you can not change it to say temp *F or C.

I understand that, what I don't understand is having your spark advance and spark retard table as (RPM vs kPA) vs (RPM vs Cylinder Mass). Whats the difference between the two, one is measuring a pressure and the other a mass....is one more accurate than the other or tell you different information?


thank you,

double

[3strokeEngine]

Question?
For spark advance and retard table in VCM Scanner, what are the X & Y axis suppose to be? I noticed that on Chopper Docs video he had RPM vs cylinder mass.
Reason I ask is because the default is RPM vs kPA. The only thing you can do to the axis is change the units but you will only be allowed to change units of similar meaning. So you can change from kpa to psi to vac, but you can not change it to say temp *F or C.

I understand that, what I don't understand is having your spark advance and spark retard table as (RPM vs kPA) vs (RPM vs Cylinder Mass). Whats the difference between the two, one is measuring a pressure and the other a mass....is one more accurate than the other or tell you different information?


thank you,

double

You want the X and Y axis to match exactly with the X and Y axis in the tune file. RPM vs MAP is useless if the tune file uses RPM vs Cyl air mass.
you can do this easily by going into the tune, right clicking on the table, Column axis or Row axis and click copy labels. Then paste those labels into your scanner and setup the the scanner to use Cyl airmass on the correct axis.

[2xLS1]

Question?
For spark advance and retard table in VCM Scanner, what are the X & Y axis suppose to be? I noticed that on Chopper Docs video he had RPM vs cylinder mass.
Reason I ask is because the default is RPM vs kPA. The only thing you can do to the axis is change the units but you will only be allowed to change units of similar meaning. So you can change from kpa to psi to vac, but you can not change it to say temp *F or C.

I understand that, what I don't understand is having your spark advance and spark retard table as (RPM vs kPA) vs (RPM vs Cylinder Mass). Whats the difference between the two, one is measuring a pressure and the other a mass....is one more accurate than the other or tell you different information?


thank you,

double

I don't know what you are looking at but the only spark tables that are RPM vs MAP kPa are 96-99 4.3L, 5.0L, and 5.7L Vortecs. Well 93-97 LT1s are too but you can't look at those with HPT. All Gen 3 engines and up are going to be RPM vs Cyl Airmass for spark control. Are you sure you're not looking at VE which is RPM vs MAP kPa?

[cobaltssoverbooster]

you can not switch between map pressure and cylinder airmass. those are two different types of units. like i mentioned previously if you have map pressure then you can change it to psi, vac, etc. (pressure units)
for cylinder airmass you can only change between units of mass which would be mg, g, kg, micro lbs, and lbs.

the reason people change units of axis is because they are typically more comfortable reading one unit type over another. Like kids in the U.S. learn imperial units and kids everywhere else learn metric units. Just because hpt gives you access to read tables does not mean you can change the axis units like a standalone computer. hpt follows the oem tuning equations which means no changing kpa to g.

What video are you watching and can you post an ecu file so we know what you have?

[jmbusch90]

you can not switch between map pressure and cylinder airmass. those are two different types of units. like i mentioned previously if you have map pressure then you can change it to psi, vac, etc. (pressure units)
for cylinder airmass you can only change between units of mass which would be mg, g, kg, micro lbs, and lbs.

The reason people change units of axis is because they are typically more comfortable reading one unit type over another. Like kids in the U.S. learn imperial units and kids everywhere else learn metric units. Just because hpt gives you access to read tables does not mean you can change the axis units like a standalone computer. hpt follows the oem tuning equations which means no changing kpa to g.

What video are you watching and can you post an ecu file so we know what you have?

I might've caused some confusion, this isn't on the VCM editor side, this is on the VCM scanner side. Sorry for the lack of clarification on that everyone.

Here's, this video I noticed it on and then noticed that my units on my VCM scanner differed.

https://www.youtube.com/watch?v=vAQhoETdsRg

But it make it easier I posted a snippit of my VCM scanner spark table and the one I'm from Chopper Doc's.

[cobaltssoverbooster]

that is a VE tuning video. The ignition advance does not follow the same axis units. Around 6:50 you can see the axis change because he takes the high octane map and copies it so it can be pasted to the low octane map. All techniques after this point are all in regards to fuel tuning.
Although Doc doesn't specifically talk about tuning spark advance you can see his spark advance in the scanner also has cylinder airmass (g) axis on it in the video for a brief amount of time (13:46). After this point Doc shows you how to go about making axis match between your target editor table and the histogram table in the scanner. Again, this step is in regards to the VE table (fuel table), and not an ignition table. This whole video is based on setting a default starting point and showing how to go about making fuel adjustments. If your trying to watch this video to learn how to tune ignition, then i hate to say this but your in the wrong video and need to fix this error on your end fast before things get out of control.

this still goes back to "the axis need to match the tables you are tuning". If your editor tables don't match your histograms tables, your calibration will end in disaster.
if you tune the ignition then you need to record cylinder airmass (g)...if you tune fuel maps (particularly the base VE table as Doc is doing), then you need to record map pressure (typically in kpa).

[jmbusch90]

that is a VE tuning video. The ignition advance does not follow the same axis units. Around 6:50 you can see the axis change because he takes the high octane map and copies it so it can be pasted to the low octane map. All techniques after this point are all in regards to fuel tuning.
Although Doc doesn't specifically talk about tuning spark advance you can see his spark advance in the scanner also has cylinder airmass (g) axis on it in the video for a brief amount of time (13:46). After this point Doc shows you how to go about making axis match between your target editor table and the histogram table in the scanner. Again, this step is in regards to the VE table (fuel table), and not an ignition table. This whole video is based on setting a default starting point and showing how to go about making fuel adjustments. If your trying to watch this video to learn how to tune ignition, then i hate to say this but your in the wrong video and need to fix this error on your end fast before things get out of control.

this still goes back to "the axis need to match the tables you are tuning". If your editor tables don't match your histograms tables, your calibration will end in disaster.
if you tune the ignition then you need to record cylinder airmass (g)...if you tune fuel maps (particularly the base VE table as Doc is doing), then you need to record map pressure (typically in kpa).

Yes sir, I understand that 110%, you want your tables to match from what you're pulling from the ECM from VCM editor to how you're logging the information in VCM suite. That's like trying to tune a pressure feedback loop as if it were a level feedback loop. I also understand its to get a base line for your VE table because the name of the video is "Tuning VE on early GM". With that being said, I understand that the two tables control two different functions.

Now, I don't think you understand my question at all. Let me try to rephrase it.

All I'm asking is why is his y-axis variable in the photo pointed to Cylinder airmass while the default variable is pointed to manifold air pressure (kPA) in his VCM scanner. Thats all I'm asking.

Thank you,

double

[cobaltssoverbooster]

maybe this is what your looking for. If you initially open the vcm scanner there will be default tables loaded in so there is something present for you to see. It does not preset these tables based on your connected vehicle. This means your axis may not be proper to the editor and may require a manual update through the scanner settings.

[kingtal0n]

I recommend reading the stand-alone guides from AEM, megasquirt, holley, haltech, bigstuff before trying to understand the factory computer

[jmbusch90]

maybe this is what your looking for. If you initially open the vcm scanner there will be default tables loaded in so there is something present for you to see. It does not preset these tables based on your connected vehicle. This means your axis may not be proper to the editor and may require a manual update through the scanner settings.

Okay that makes sense, I don't see an update option. How do you execute this update?

[jmbusch90]

I recommend reading the stand-alone guides from AEM, megasquirt, holley, haltech, bigstuff before trying to understand the factory computer

This can be found by a simple google search?

[kingtal0n]

This can be found by a simple google search?

The manuals are downloadable free for 10-20 years.
Just like a textbook on physics or whatever. But people don't actively spend free spare time searching for them for fun.

You have to want to know how computers work, how electronics function aside from just copy and paste.

[cobaltssoverbooster]

update isnt like a software update. you need to right click the histogram to access the chart formatting screen and then change the values by hand.