Running a 2006 GTP L32 engine (with mods below) and using a 2003 PCM for engine/trans control. Using the stock 03 GTP timing tables which are a function of air mass and RPM's. I was able to get a tuning file from an 05 Grand Prix w L32. The later L32 table that I received appears to have far more agressive timing values that add 3-*4* of timing at the higher RPM values. Looking for a way to confirm this.
This is the timing that I wish to try.



Can anyone confirm that this table contains the stock L32 timing numbers? If so I would like comments from those that have tuned and possibly tried these timing numbers as they should provide more horsepower (if they are safe to use) .

Darth, BWWguru, and Darkhorizon; can you hear me?

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

If you have a scanner try it and watch out for KR. I would recommend: Drive, Scan, up timing 1* ONLY on Cells where there is NO KR and YOU actually logged data, Repeat.

I tryed this with the 2004 GTP table and couldn't run it as I ALWAYS got partial throttle KR. There are a few more tables such as AFR spark modifier and Air Temp spark that come into play too. These tables should also be modified to match the updated Good Fuel Spark, PE settings. However, I found that the end result is similar (little less) timing when all the tables combine together. I recommend to just change Cruise timing to 40*+ as that is where you will gain 2-3 MPG. WOT can be tweaked too but I couldn't run more than 17* (tables combined) unless I had higher octane fuel.

Bottom line is always make a backup and play around with the other settings as there are many many combinations of values. Some will work while others will yield KR and less than optimal results.

The L32 is definitely more aggressive than the L67. For your mods, I would definitely bump up the timing and disable any of the abuse modes. Your only holdback that would cause KR would be stock exhaust manifolds. I was able to free up so much more power with powerlogs and headers.
More importantly, once you get the injectors dialed in, disable the MAF sensor and set the PE to not enter that mode. Datalog and tune the VE and then enable the MAF and dial it in. You should then be able to tweak the timing a few degrees because the rest of the tune will be in line.
Dave

------------------

www.hausofguru.com

quote Originally posted by bmwguru: The L32 is definitely more aggressive than the L67. For your mods, I would definitely bump up the timing and disable any of the abuse modes. Your only holdback that would cause KR would be stock exhaust manifolds. I was able to free up so much more power with powerlogs and headers. More importantly, once you get the injectors dialed in, disable the MAF sensor and set the PE to not enter that mode. Datalog and tune the VE and then enable the MAF and dial it in. You should then be able to tweak the timing a few degrees because the rest of the tune will be in line. Dave

Tuning VE serves zero function, and is impossible to do without a wideband as you can not use LTFTs. A car with a VE table of all zeros runs the same as one with a "mega tuned" VE table.

The reason for the extra timing in the 04+ files was only because there was a different air/fuel spark modifier that was much less aggressive.

Some differences of opinion here but all inputs are always welcome. I've read about bmwgurus tuning method before but I'll first compare the spark correction to see what the relationship is to the air mass-rpm-timing table.
In checking I find that the spark correction/AFR correction is identical for the 03 and 05 PCM's. The other point is that this table is only used in lean cruise mode. Not sure what you mean.
------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 02-04-2012).]

quote In checking I find that the spark correction/AFR correction is identical for the 03 and 05 PCM's.

Hmm, maybe the air temp spark table? I know that the actual timing output is about the same 16-17 degrees at wot.

quote Originally posted by darkhorizon: Tuning VE serves zero function, and is impossible to do without a wideband as you can not use LTFTs. A car with a VE table of all zeros runs the same as one with a "mega tuned" VE table.

I'm not trying to say that you are incorrect, but I feel I should explain what the VE table is for so that Dennis can determine if a VE tune is important for him or not.

The MAF and VE tables are two sources that the vehicle's computer uses to determine how much fuel is injected based on the the airflow read by the MAF sensor or VE table. The idea is to modify these tables so that there is less error for the pcm to trim out with the LTFT's.
The pcm uses the MAF data to calculate the fuel requirement to meet the desired A/F ratio only when the airflow is stable across the MAF. It is typically stable at idle, cruising and at WOT. During the short period of time the MAF is unable to get a stable reading, the pcm will use the VE table instead of the MAF to determine the amount of fuel needed to reach the desired A/F ratio. This has nothing to do with using a wideband because the MAF and PE (power enrichment) mode are disabled. The wideband is needed for WOT MAF tuning and ensuring that the PE is being met.

Once you get the VE table dialed in so that the LTFT's are at 3% or better, then tuning the MAF without worrying that the MAF is influenced by the VE table being incorrect.

If you are at full throttle most of the time, or drag racing, then the VE is not important to get dialed in. I would then worry about tuning the MAF in WOT mode with a wideband. If you plan to use your car to drive to work, or in a Fiero cruise, then VE and MAF tuning is pretty important to keep from having the pcm compensate the fueling with the fuel trims by too much.

This takes about an hour or so to do and it benefits a daily driver.

Dave

[This message has been edited by bmwguru (edited 02-05-2012).]

quote Originally posted by bmwguru: I'm not trying to say that you are incorrect, but I feel I should explain what the VE table is for so that Dennis can determine if a VE tune is important for him or not. The MAF and VE tables are two sources that the vehicle's computer uses to determine how much fuel is injected based on the the airflow read by the MAF sensor or VE table. The idea is to modify these tables so that there is less error for the pcm to trim out with the LTFT's. The pcm uses the MAF data to calculate the fuel requirement to meet the desired A/F ratio only when the airflow is stable across the MAF. It is typically stable at idle, cruising and at WOT. During the short period of time the MAF is unable to get a stable reading, the pcm will use the VE table instead of the MAF to determine the amount of fuel needed to reach the desired A/F ratio. This has nothing to do with using a wideband because the MAF and PE (power enrichment) mode are disabled. The wideband is needed for WOT MAF tuning and ensuring that the PE is being met. Once you get the VE table dialed in so that the LTFT's are at 3% or better, then tuning the MAF without worrying that the MAF is influenced by the VE table being incorrect. If you are at full throttle most of the time, or drag racing, then the VE is not important to get dialed in. I would then worry about tuning the MAF in WOT mode with a wideband. If you plan to use your car to drive to work, or in a Fiero cruise, then VE and MAF tuning is pretty important to keep from having the pcm compensate the fueling with the fuel trims by too much. This takes about an hour or so to do and it benefits a daily driver. Dave

ON the 3800's there are a ton of posts on HP Tuners and other sites. It appears that for the majority of 3800's the VE table is not used. Most users have reported they can zero out their VE table and the car will run fine. Most say if they disconnect their MAF, it wont run. I recall reading a post from Bill at HP tuners - and he concluded that many 3800 PCMs do not use the VE tables at all, but there are a few out there that do....
------------------
87 Formula Clone, 3800SC, 3.4 Pulley, 4T65E-HD, HP Tuners, AEM Wideband, 12.98 at 103.4 1/4 mile, Regal GS Gauge Cluster, S-10 Brake Booster Upgrade.

[This message has been edited by DimeMachine (edited 02-05-2012).]

quote Originally posted by DimeMachine: ON the 3800's there are a ton of posts on HP Tuners and other sites. It appears that for the majority of 3800's the VE table is not used. Most users have reported they can zero out their VE table and the car will run fine. Most say if they disconnect their MAF, it wont run. I recall reading a post from Bill at HP tuners - and he concluded that many 3800 PCMs do not use the VE tables at all, but there are a few out there that do....

I don't want to get too far off the original topic. When you do a VE tune, you don't physically disconnect the MAF, you set it to fail at 0, so that it fails. This will set the check engine light and then it will rely on the VE. When finished, put the MAF fail at the original number to tune the MAF.

I did my VE tune for my 3800 and it did bring my fuel trims into spec. It could have just been the MAF tuning, but regardless I am very content with the way my Fiero drives.

Dave

I just need to pop in and say that my car is dead nuts on the tune and so perfect in open loop.

------------------
Turbo 3800 E85 5spd spec5
11.54@132.7

quote Originally posted by bmwguru: I'm not trying to say that you are incorrect, but I feel I should explain what the VE table is for so that Dennis can determine if a VE tune is important for him or not. The MAF and VE tables are two sources that the vehicle's computer uses to determine how much fuel is injected based on the the airflow read by the MAF sensor or VE table. The idea is to modify these tables so that there is less error for the pcm to trim out with the LTFT's. The pcm uses the MAF data to calculate the fuel requirement to meet the desired A/F ratio only when the airflow is stable across the MAF. It is typically stable at idle, cruising and at WOT. During the short period of time the MAF is unable to get a stable reading, the pcm will use the VE table instead of the MAF to determine the amount of fuel needed to reach the desired A/F ratio. This has nothing to do with using a wideband because the MAF and PE (power enrichment) mode are disabled. The wideband is needed for WOT MAF tuning and ensuring that the PE is being met. Once you get the VE table dialed in so that the LTFT's are at 3% or better, then tuning the MAF without worrying that the MAF is influenced by the VE table being incorrect. If you are at full throttle most of the time, or drag racing, then the VE is not important to get dialed in. I would then worry about tuning the MAF in WOT mode with a wideband. If you plan to use your car to drive to work, or in a Fiero cruise, then VE and MAF tuning is pretty important to keep from having the pcm compensate the fueling with the fuel trims by too much. This takes about an hour or so to do and it benefits a daily driver. Dave

So... what were you using to tune this magical VE table? LTFT's? Wideband?

If you get bored, unplug your IAT the next time you are in VE mode / maf fail mode, and watch your LTFT's..... lol!

None of my cars "spend most of their time at wot" either, so IDK if you are trying to imply that I am lazy or stupid by that comment either....

I wasn't calling you lazy or stupid.....

Back to the original question....yes that table is a stock L32 timing table

I'm a novice to these subjects so forgive me if I make a stupid comment.... at this point I'm just trying to gain a better understanding of these topics.

I too have noticed that that most 3800 tuners don't bother to mess with VE tables while claiming they aren't used. With that said, what's the harm/danger in attempting to tune the VE tables or is it just a matter of why do it if its not needed? Seems to me that if they aren't used then there's no harm in tuning them and if they are used then obviously there is a benefit.

BMWGuru... you obviously seem to disagree with the idea that the VE tables aren't used right? When do you feel that the VE tables are most used then...during changes in "acceleration"/airflow? Do you have any recommended reading sources for learning to tune? More information is always better

quote Originally posted by GraterFang: I'm a novice to these subjects so forgive me if I make a stupid comment.... at this point I'm just trying to gain a better understanding of these topics. I too have noticed that that most 3800 tuners don't bother to mess with VE tables while claiming they aren't used. With that said, what's the harm/danger in attempting to tune the VE tables or is it just a matter of why do it if its not needed? Seems to me that if they aren't used then there's no harm in tuning them and if they are used then obviously there is a benefit. BMWGuru... you obviously seem to disagree with the idea that the VE tables aren't used right? When do you feel that the VE tables are most used then...during changes in "acceleration"/airflow? Do you have any recommended reading sources for learning to tune? More information is always better

When I tune all 3800 setups, I follow the same path every time. I've been playing with the Saab 2.8t tune for my own car and it is totally different, but I still follow the same path.

Here is where I learned a lot of my tuning skills.....the rest was hands on with my own car. I'd make some changes to see what it would do.

http://www.thetuningschool.com/

The other thing is browse hptuners.com forum and there are other forums I frequent to gain some knowledge from. DH will probably say something bad about the tuning school, the price is more than he invested in his swap, but to each their own.

Some say don't bother with tuning the VE unless you have time or want to be a perfectionist. Others say tune it so that the pcm will know when the MAF is out of spec. My personal preference is to tune for it so that I can be 100% certain my MAF is dialed in or falls out of spec. We did have one cammed 3800 that kept stalling when stopping. I did a my typical VE and MAF tune and the stalling stopped and fuel trims were in spec. Though it was probably more the MAF tuning that fixed it, but like I said before....I follow the same path to keep myself consistant.

After I sell my shop, I plan to teach seminars or work for a tech help dept. to teach/help others.....moreso about German car diagnostics and theory rather than tuning.

[This message has been edited by bmwguru (edited 02-05-2012).]

Thanks and good luck with your future endeavors... it sounds like you really know what you're doing so I'm sure it'll go well

At this point I am mostly just browsing various forums including HPTuners. There's a lot to be learned through reading and experimentation. I'm sure the tuning school courses are worth it but its also more then I'm prepared to invest at this time as working on cars is just a hobby for me. It is interesting though that you seem to be one of the few people that I have found so far that actually recommend tuning the VE tables for the 3800 and was curious if you had anything more to add to the subject. I guess more searching is in order.

I just tune it the way I was taught. VE is good for knowing if the MAF is out of spec, and taking over for the small times that the MAF is not controlling the fueling.

quote Originally posted by bmwguru: I just tune it the way I was taught. VE is good for knowing if the MAF is out of spec, and taking over for the small times that the MAF is not controlling the fueling.

I purchased HP tuners for my 3800 fiero and my LS1 Trans AM. I studied up mostly for the LS1 and when I started reading up on the 3800's it became clear right away that most of the GM 3800's do not reference the VE table like many other GM products do. I did disconnect my MAF and my car would not run. I did this as a test because if it would still run, it would have to be running because it was using the VE table. I wish I had done the second test which would be to zero out the VE table (with the MAF connected properly) and drive around with my wideband connected and see if the engine still operates properly. I am convinced that in my case it would. Again, there is a thread in depth about this where Bill from HP tuners investigated this same discussion and he determined that a few of the GM 3800s do use the VE table, but for some reason, GM programed most 3800 GM PCMs to not use the VE Table. If I decide to start modding my LS1 this summer, I believe a VE tune is indeed beneficial for that engine/pcm setup.

I am a beginning tuner and definately not claiming to be better than anyone. The purpose of this email is simply to share what I have learned about this topic - so far.

quote DH will probably say something bad about the tuning school,

Tuning school is probably fine and dandy.. but it doesnt tell you anything other than extremely general crap... Every different setup you will run across requires completely different things, so I dont see how you would ever benefit from knowing everything about nothing.

I haven't been to tuning school but from corresponding with and knowing other people who tune, and from doing tuning myself,this is my understanding of the VE table.
VE values are used in conjunction with the MAF to set the fueling values. The MAF measures the actual air mass entering the engine and the VE table provides a reference value. For instance when the air mass is quickly changing the MAF values suffer some inaccuracy. In this case the PCM blends the MAF signal with the VE table to derive a set calculation for accurate fueling. Under 4000 RPM the MAF sensors readings are somewhat unsteady so if the VE table values are set correctly there is always a secondary reference. I believe that what bmwguru is saying is that if you disable the MAF ( in the program) the fueling reverts to the values in the VE table so it becomes easy to tune the fueling values in the table. Once the VE values are established it should make tuning of the MAF easier. I also believe that the MAF is only used for cruise and general driving conditions under 40000 RPM. At WOT the PCM falls out of closed loop operation and VE, and PE table values are used to set the AFR.
Now as far as timing goes, the .24 .32gm/cyl range is for low rpm values the .36--.72 are the midrange values and above .72 gm/cyl up to say .76 gm/cyl we have the high end values. The table that I posted above adds a considerable amount of timing.
This is the stock 03 timing table (or close to it)

Since I compared all of the other tables in the PCM program that affect timing and they are identical, I can only assume that the cooler intake charge of the gen 5 supercharger and the other small mods allows the series III engine to use far more agressive timing values. Now to find out if the intercooler and 3.4" pulley will allow these numbers without knock retard. I am running 11 psi of boost on 93 octane fuel. I am guessing that its also time for Powerlogs or headers. Already have a 3" exhaust. We'll see.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 02-05-2012).]

Not sure if there are any differences in any of the other tables, but tinytuner has more tables than HP Tuners.

On a LS v8 car the ve table is used up until around 4000 rpm, around that point ve and MAF are blended, then high rpm it goes full MAF. On a V6 car this is not the case. There are a few operating systems that use VE, but most to not. Also there is a check in the PCM for MAF failure mode. Many use default air table, not VE for MAF failure backup. Forcing a MAF fail may not even let you properly tune VE. If you are not using TinyTuner for a v6 car, you are really missing some important stuff that HP Tuners has decided you don't need.

------------------
11.425 @115.60
Best 60' 1.543 seconds
3800 S/C 4T65E

New combo : Billet 6262 Precision turbo, PT1001 intercooler, ST1 cam, 130lb springs, comp pushrods, HV3, otherwise stock L36.

quote Originally posted by LFiero67: Not sure if there are any differences in any of the other tables, but tinytuner has more tables than HP Tuners. On a LS v8 car the ve table is used up until around 4000 rpm, around that point ve and MAF are blended, then high rpm it goes full MAF. On a V6 car this is not the case. There are a few operating systems that use VE, but most to not. Also there is a check in the PCM for MAF failure mode. Many use default air table, not VE for MAF failure backup. Forcing a MAF fail may not even let you properly tune VE. If you are not using TinyTuner for a v6 car, you are really missing some important stuff that HP Tuners has decided you don't need.

I guess that the ideas and opinions about the VE table, its purpose and how to optimize will go on forever.
Tiny Tuner is an open sourced editor. It can't be used to flash a PCM or extract a file from a PCM. You will still need HPtuners or DHP to flash/scan but agreed it does have tables that HP and DHP do not provide. Its a free download and V6 friendly. I guess you can probably use it to edit a file downloaded by the common flash/scan editors. Worth checking out.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

quote I guess that the ideas and opinions about the VE table, its purpose and how to optimize will go on forever.

Its not a debate... its pure fact... Look at the assembly if you dont believe me... Its a table that is not reference by anything, and has no use by anything via the code... You cant say it has any bearing on a single part. In most files (specifically wbody files) the VE table exists as a maf fail default and is referenced by the check bit that determines airmass/rpm mode or map sensor fail mode.

Just because "mr I went to tuning school" says one thing does not automatically make logic and reasoning completely stupid to consider.

quote Originally posted by darkhorizon: Its not a debate... its pure fact... Look at the assembly if you dont believe me... Its a table that is not reference by anything, and has no use by anything via the code... You cant say it has any bearing on a single part. In most files (specifically wbody files) the VE table exists as a maf fail default and is referenced by the check bit that determines airmass/rpm mode or map sensor fail mode. Just because "mr I went to tuning school" says one thing does not automatically make logic and reasoning completely stupid to consider.

If you have done the code disassemby then I have no reason to doubt your info. GM does some strange things and in the case of the 3800 application they very well may have intended to use the VE table solely as a backup in the case of MAF failure. I run an LS1 MAF and after importing the new MAF values (supplied by sinister) I did not notice any problems whatsoever using the stock VE table values. However, the fueling did change as the MAF curve, AE and PE numbers were teaked. Info from a tuner that did his fueling strictly from a MAF tune seems to confirm that its output is the important fueling reference.. By canceling the MAF signal and tuning the VE table values, then you are stating that this only sets the MAF default values in case of MAF failure.
Such being the case, we can assume that during normal operation, the MAF curve is the main reference for fueling but I believe that AE modifier and PE table values must also be considered. The PE numbers do seem to make a difference in WOT fueling.
As for the 05 GTP timing chart that I originally posted, after doing an analysis of the true operating points of the engine; despite its more agreessive appearance, it only ends up adding a couple of degrees of timing at the higher RPM's and flow rates. I'm going to program that table in first chance but right now its 25* outside and I'll wait for it to warm a bit.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "