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rsicard
01-21-2015, 05:32 AM
In the process of tuning a 1994 Chevrolet Suburban with a Big Block. Found a 0E mask binary that works good with the 16197427 ECU. The binary file found is a BJKW 0E. The 454 big block was bored and stoked to 489 cu in. The cylinder heads were replaced with Edelbrock Oval Port heads. Also an Edelbrock TBI to batch MPFI conversion intake manifold was installed. The throttle body now has the upper fuel portion taken off and lower portion used as an air valve with TPS and IAC.

Today adjusted the cylinder displacement and fuel flow constant upward by the percentage of change in displacement. Burned a BJKW+ file to chip and installed in ECU. Set the Autoprom APU1 in the vehicle and recorded the BLMs for on and off idle. The idle BLMs are right on the money at 128. The off-idle BLMs need some adjustment and not all that bad.

Need help in identifying which parameter to use in the tables of the BJKW 0E mask binary. I have attached a jpeg file of what I believe are the applicable parameters. Would like confirmation from you folks that I am headed in the proper table items to modify the on and off-idle VE tables. Trying to locate and identify the two VE table to use to apply BLM spreadsheet corrections to. Also attached is the BJKW 0E binary file for inspection. Please advise. Thanks.

dave w
01-21-2015, 09:03 AM
Open Throttle VE vs MAP vs RPM is for adjusting ~ Off Idle

Idle VE vs MAP vs RPM is for adjusting ~ Near Idle

It's a good plan to use closed loop data.

dave w

JeepsAndGuns
01-21-2015, 03:24 PM
Have you adjusted the injector offset Vs battery voltage? Since you have installed MPFI injectors, this needs to be changed to match the new injectors as it can have a big effect on how it runs. Are you using junkyard injectors or ones from a aftermarket company?

Nasty-Z
01-21-2015, 07:30 PM
How is the idle quality with your setup ? I wasn't able to stabilize the idle and have it be respectable with my 502 setup until I went to PFI mode with the '7427. You didn't mention camshaft so that might be a difference.

Your setup is very similar to mine before I went with the 502 , my original 454 was also bored and stroked to 489 , although it wore first a set of Vortec heads then a set of AFR heads and a few different cams .

TOM

JeepsAndGuns
01-22-2015, 02:49 AM
How is the idle quality with your setup ? I wasn't able to stabilize the idle and have it be respectable with my 502 setup until I went to PFI mode with the '7427.

I didnt even think about that. You did do all the required mods to run MPFI right?

rsicard
01-22-2015, 03:06 AM
Dave:

Thanks again for the assistance. Don't understand the statement "It's a good plan to use closed loop data". Please expand on the statement please. Thanks.

dave w
01-22-2015, 03:14 AM
Dave:

Thanks again for the assistance. Don't understand the statement "It's a good plan to use closed loop data". Please expand on the statement please. Thanks.

Closed loop is when the computer takes full control of both fuel and spark based on the information from the sensors (Knock, TPS, O2, MAP, RPM, & CTS). Tune using only the data that was recorded when the computer was in closed loop.

dave w

rsicard
01-22-2015, 03:14 AM
Tom:

No problems with idle quality after installing Edelbrock TBI to batch injected MPFI via the 16197427 ECU. Did not know about the injector offset vs battery voltage. The conversion was done some 8 years ago. Purchased Craig Moates AutoProm APU1 which was of the initial production run. Talked to Craig and received some advice from him. Unaware about modifying the ECU and Edelbrock said nothing about it. Just did the conversion and it worked out. The Edelbrock kit (chose 502 cu in kit w/29 Lb/Hr injectors) came with new Intake Manifold, new Magnetti Marelli Pico Injectors, new fuel pump, and new programmed memory chip for ECU and other small hardware.

rsicard
01-22-2015, 03:17 AM
Closed loop is when the computer takes full control of both fuel and spark based on the information from the sensors (Knock, TPS, O2, MAP, RPM, & CTS). Tune using only the data that was recorded when the computer was in closed loop.

dave w

Dave: Did exactly that with a BJKW 0E altered binary and the Suburban is running fairly well. In the process of using your spreadsheet and BLM data to correct the BJKW binary. Looks to be a VERY good method/process. Again, thanks for all your assistance.

Regards,

Rolly
Tucson, Arizona

rsicard
01-22-2015, 03:26 AM
I didnt even think about that. You did do all the required mods to run MPFI right?

As I explained to TOM, the Edelbrock conversion was done some 8 years ago. Unaware of all this stuff when it was done. Worked fairly well. Used Moates APU1 to make changes about which I knew absolutely NOTHING! Still it worked out after capturing the Edelbrock binary supplied on their chip. Also purchased another programmed chip from which to extract data, although I had little idea about what I was doing. Still puzzled as to what the ECU mods really do. Still have not done them and yet the stock, with exception of the flash chip, ECU and Engine run just fine.

rsicard
01-22-2015, 04:00 AM
Gentlemen: Just to provide some background about myself, I really like working on Internal Combustion Engines especially the Small Block Chevrolet. It is a compact package capable of much horsepower depending on how much a person spends on building up one. I was in Aviation Electronics, known as Avionics, for 38+ years. Electronics is nothing new to me. Yet, getting through TunerPro RT V5.x is somewhat of a challenge. Have read many of the posts here on gearhead-efi. Am very greatfull for this Internet Site as it has been a wealth of knowledge. Many of you fellows have extensive knowledge just through exposure doing your own GM EFI projects. A special thanks to Dave W. as he had been VERY helpful. I have two chevrolet trucks that I work on. One a 1994 BBC Suburban and the other a 1995 Chevrolet C1500 2WD pickup that is in good condition except it leaks and uses engine oil. Am preparing a 350 Vortec and will be using a BBC TBI throttle body on top of a 4 barrel manifold with adapter. Just added a LT-4 Hot Cam to the Vortec and today the stronger Crane Cams valve springs came via UPS. Need to install these and mock up and set the fuel pressure regulator on the BBC throttle body. Then run the Vortec on my home brew run-in stand with a Holley 4 barrel carb. Also have a harness for the 16197427 ECU. Shall see if I can get the harness and BBC throttle body all mocked up on the run-in stand which provides NO dynamic load whatsoever to the Vortec. At least I can check for oil leaks etc. before installing same in the '95 pickup.

It is nice to have you fellow to consult with.

Regards,

Rolly
Tucson, Arizona

tayto
01-22-2015, 05:57 AM
if you have a multiport intake and injectors I have no idea why you would want to run them in a tbi fueling mode. ya it'll run but leaves a lot on the table no?

Nasty-Z
01-22-2015, 05:15 PM
if you have a multiport intake and injectors I have no idea why you would want to run them in a tbi fueling mode. ya it'll run but leaves a lot on the table no?

The calibration from Edelbrock runs the 8 MPFI injectors in a batch fire mode , this setup is not a "true" MPFI setup but rather a small upgrade to get the fuel flow from the factory TBI out of the air stream and directly into the ports. The 16197427 will not support true MPFI.

As I said in my earlier post , I tried to use the factory Edelbrock calibration on both my original 454 and the replacement 502 (509) in the '7427 , It ran OK , but I believe it left a lot on the table with the PCM in the original TBI mode. I switched to PFI mode in the PCM (Jumper mod only , no sense resistor mods) and it runs and idles much better.

Just my experience , the OP states his idles just fine the way it is so he should be good to go.

TOM

rsicard
01-22-2015, 06:11 PM
The calibration from Edelbrock runs the 8 MPFI injectors in a batch fire mode , this setup is not a "true" MPFI setup but rather a small upgrade to get the fuel flow from the factory TBI out of the air stream and directly into the ports. The 16197427 will not support true MPFI.

As I said in my earlier post , I tried to use the factory Edelbrock calibration on both my original 454 and the replacement 502 (509) in the '7427 , It ran OK , but I believe it left a lot on the table with the PCM in the original TBI mode. I switched to PFI mode in the PCM (Jumper mod only , no sense resistor mods) and it runs and idles much better.

Just my experience , the OP states his idles just fine the way it is so he should be good to go.

TOM

By true MPFI, does that mean sequential MPFI versus batch MPFI? Still do not understand from an electronics standpoint why the resistors are removed and a jumpers installed.

Nasty-Z
01-22-2015, 08:14 PM
By true MPFI, does that mean sequential MPFI versus batch MPFI? Still do not understand from an electronics standpoint why the resistors are removed and a jumpers installed.

By true MPFI I mean sequential , the '7427 will not support this . The normal "TBI" mode is injectors fire every 2nd DRP , the PFI mode I run the '7427 in is every 4th DRP (The '7427 can also run CPI mode which is every DRP). What I experienced in running the PCM in TBI mode with the 8 injectors is that the PW went so low idle quality started to be affected.

I do not know the whole story behind the sense resistor bypass , I was told for the conversion to be 100% reliable it needed to be done , I have over 75K and 10+ years on my conversion on only the Netres mod .

TOM

rsicard
01-22-2015, 09:34 PM
Thanks much for the reply. Do not know what DRP stands for. Where can I find something about DRP and Netres mod? Please respond.

Rolly

rsicard
01-22-2015, 10:00 PM
Just came to me what DRP is. Must be Distributor Reference Pulse. Still unable to find something about Netres mod.

rsicard
01-22-2015, 10:29 PM
Nasty-Z:

Which mode, PFI, TBI, MPFI, should I run and how does the ECU get into these different modes? Is there something written about these different modes that can be read? Do I need to be in the Port Fuel Injection (PFI) mode and install the jumper in the Memcal? Do the resistors need to be shorted or removed? Please advise.

dave w
01-22-2015, 11:06 PM
When I think of NetRes, I think of Limp Home Mode, where a set of fixed resistors in the Memcal will set the fuel delivered by the injectors at a fixed pulse width.

When I think of Cylinder Select, I think of the injector firing sequence based on Distributor Reference Pulse (DRP). Cylinder Select is a voltage, which will range from 0 VDC to 5 VDC. The Memcal sends the Cylinder Select voltage to the PCM to set up injector firing sequence.

It's my understanding the '7427 MPFI conversion requires a Memcal modification to set up the correct MPFI Cylinder Select voltage.

It's my understanding NetRes and the Current Sense Resistors of the '7427 are separate and unrelated components with different functions.

It's my understanding the Current Sense Resistor is modified to prevent the '7427 from defaulting to TBI Mode.

There is not a Factory Service Manual that I can reference to confirm my understanding of NetRes, Current Sense Resistor, Cylinder Select / DRP sequence. Most of my understanding is based on information I've read on the "Internet", which most of the time is accurate but not always.

dave w

Nasty-Z
01-22-2015, 11:35 PM
Nasty-Z:

Which mode, PFI, TBI, MPFI, should I run and how does the ECU get into these different modes? Is there something written about these different modes that can be read? Do I need to be in the Port Fuel Injection (PFI) mode and install the jumper in the Memcal? Do the resistors need to be shorted or removed? Please advise.

Rolly ,

You do not need to do the mod if your truck is running good as is , I did mine as more of an experiment as to see if I could get it "better" .

Dave is correct , it really isn't a Netres mod although it is often called that by many , it is really a jumper on the Memcal to alter the injector firing strategy of the PCM (TBI/Batch/Bank). The Memcal mod is needed to tell the injectors when to fire in relation to DRP.

That being said , here : http://www.hptuners.com/forum/showthread.php?9228-TBI-to-MPFI-netres-modification

That is a good write up by Ken Canatta of HP tuners on the modifications , he is who I first worked with way back when I first did the conversion in the early 2000's. There are many different ways to do the PFI mod that I see referenced , some say you have to do the sense resistors some say not , I really have never had someone tell me one way is better than the other , I do know that you have to do the Memcal mod , as I said I have many miles on mine with nothing more than the Memcal mod mentioned in the link and it runs good , not great , but good .

Hope this helps.

TOM

JeepsAndGuns
01-23-2015, 03:18 AM
Nasty-Z:

Which mode, PFI, TBI, MPFI, should I run and how does the ECU get into these different modes? Is there something written about these different modes that can be read? Do I need to be in the Port Fuel Injection (PFI) mode and install the jumper in the Memcal? Do the resistors need to be shorted or removed? Please advise.

This thread, post number 6, is the instructions I followed when I converted my 7427 to mpfi. http://www.gearhead-efi.com/Fuel-Injection/showthread.php?303-16197427-PCM-Information-0D
I did the resistor mod on mine cause it was listed in there to do so.

rsicard
01-23-2015, 04:27 AM
Gentlemen Dave W., Nasty-Z and JeepsAndGuns: Many thanks to all of you for all the assistance. I have two spare 16197427 ECUs. I will burn another BJKW 0E binary and install same into one of the spares. Then install it into the '94 BBC suburban and drive it to make certain the ECU is good. Then I will take it out and jumper the two resistors and apply the jumper to the MemCal. Then re-install into the Suburban and test drive it again to verify any changes to the performance of the ECU. Will also compare an un-mod'd versus mod'd ECU. If the mod'd ECU performs properly, I will proceed with fine tuning the binary to get the appropriate BLM values by altering the VE maps. Again, thanks for sharing the knowledge.

rsicard
01-23-2015, 08:07 AM
Gentlemen: Another question, does modifying the ECU cause the VE on and off idle maps to be all screwed up? Please advise. Thanks.

Rolly

Tucson, Arizona

JeepsAndGuns
01-23-2015, 03:20 PM
From what I understand, installing the jumpers changes the way the ecm fuels the engine, so I would say that yes, it will effect the fuel tables and require them to be re tuned.
Installing the jumpers was only part of the conversion. There was also changes to some of the parameters in the bin also.

rsicard
01-23-2015, 06:03 PM
Sure would be nice to know what parameters of the binary as affected by the modification. Sure would be nice to know by what percentage the fuel tables have to change. I am going to hold off on the modification until I get more experience under my belt with tuning the VE maps. Can't understand by reliability is an issue unless firing 4 injectors versus 1 is causing excessive injector driver current in the ECU.

JeepsAndGuns
01-24-2015, 02:56 AM
The resistor mods change the way it fires the injectors.
Copied and pasted from the tbi to mpfi zip file:
"Next you will need to change two resisters in the PCM. This modification is necessary to disable the Peak and Hold function of the injector drivers. The resistors are called sense resistors and sense the current to the injectors. The resistors have to be changed in order to run 8 MPFI injectors, 6 is OK but 8 puts too much current load on the resistors.
Port injectors come in two types: Peak and Hold (low impedance) and Saturated (high impedance). This modification only works for Saturated (high impedance) injectors."

So you might want to check the resistance on your injectors.

Nasty-Z
01-24-2015, 03:18 AM
The sense resistors (and the modification of them by bypassing them) in and of themselves do not change the firing strategy of the injectors , this is accomplished by the Memcal modification. The Memcal mod changes the firing mode of the Injector drivers. The sense resistor mod basically assures 100% reliability in the PFI mod by not allowing the injector drivers to enter peak and hold mode. This is the way it was explained to me by Ken from HP tuners and Dimented from TGO years ago in posts I had questioning it.

Once again , the sense resistor mod is NOT a requirement for proper operation as mine has been fine for years with only the Memcal mod. I have questioned the reasoning of doing only the Memcal mod and both the Memcal mod AND the sense resistor mod and was never able to find an acceptable answer as to which is the best way to do it . That is one of the reasons I never did the sense resistor mod on mine.


The Edelbrock injectors are manufactured by Magnetti Marelli and are of the saturated (High impeadance) type , therefore 4 injectors on each driver work fine in both TBI and PFI mode with the '7427 .

Hope this helps.


TOM

rsicard
01-24-2015, 04:28 AM
Nasty-Z:

Thanks very much for the reply as it has cleared up the sense resistor and Memcal mods. Apparently, Ken at HP tuners has the knowledge to impart upon others and this does not affect his present business. I need to go back and review the Memcal mod and how it affects the firing stategy of the injectors. I will jumper the sense resistors to keep the ECU from going into the peak and hold mode. Again, thanks very much for clearing up the understanding of these aspects.

Regards,

Rolly

Nasty-Z
01-24-2015, 06:01 AM
Apparently, Ken at HP tuners has the knowledge to impart upon others and this does not affect his present business.

There are many with a very good working knowledge of the '7427 , Ken was/is one of them . He helped me tremendously. I believe he and I were one of the first to try the PFI mode in the '7427 to work with the shortcomings of the Edelbrock MPFI conversion. Doug Stalter (ECTune on many forums) who worked for Edelbrock basically had his hands tied when the original calibrations were designed in house at Edelbrock for the conversions. This is why workarounds were discovered and it was a good thing they were , the Edelbrock calibrations were bad on a good day .

TOM

rsicard
01-24-2015, 08:19 PM
By true MPFI I mean sequential , the '7427 will not support this . The normal "TBI" mode is injectors fire every 2nd DRP , the PFI mode I run the '7427 in is every 4th DRP (The '7427 can also run CPI mode which is every DRP). What I experienced in running the PCM in TBI mode with the 8 injectors is that the PW went so low idle quality started to be affected.

I do not know the whole story behind the sense resistor bypass , I was told for the conversion to be 100% reliable it needed to be done , I have over 75K and 10+ years on my conversion on only the Netres mod .



TOM

Nasty-Z: Trying to understand 2nd DRP for TBI and 4th DRP for PFI. Seems to be backwards as far as idle quality is concerned. Need to know a lot more about how DRP is being processed by the ECU.

Rolly

Nasty-Z
01-25-2015, 07:41 AM
Nasty-Z: Trying to understand 2nd DRP for TBI and 4th DRP for PFI. Seems to be backwards as far as idle quality is concerned. Need to know a lot more about how DRP is being processed by the ECU.

Rolly

With the injectors firing every 2nd DRP (TBI mode) the Pulse width of the now 8 injectors (especially if you upgraded to the 29#/hr units) becomes very low. This is a result of the PCM commanding an injector pulse every 2nd DRP and essentially overfueling at idle and part throttle. Once the fueling is expanded to an injector pulse once every 4th DRP the injector pulse width is restored to a more tolerable level , resulting in a cleaner idle and an easier transition to tune from idle to off idle.

Pin 56 on the Memcal is the cylinder select pin , depending on what the voltage is at on pin 56 it controls what fuel mode is selected.

There is a chart somewhere on this site , I think by 1Project2Many , that describes what fueling mode is selected by what voltage is seen on pin 56. I will try to search it out if I get a minute.

Hope this helps.

TOM

delcowizzid
01-25-2015, 08:14 AM
we dont veiw voltages but the resistance withen the netres chip that changes the voltage on the pins.TBI to pfi v8 actually looks like it needs a couple of mods with resisters to be factory correct. anyone care to measure the resistance of the pins above on a TBI memcal to see if it has the 7.5K between the 2 pins of the v8 memcal setup
http://pcmhacking.net/forums/download/file.php?id=3491

rsicard
01-25-2015, 06:37 PM
With the injectors firing every 2nd DRP (TBI mode) the Pulse width of the now 8 injectors (especially if you upgraded to the 29#/hr units) becomes very low. This is a result of the PCM commanding an injector pulse every 2nd DRP and essentially overfueling at idle and part throttle. Once the fueling is expanded to an injector pulse once every 4th DRP the injector pulse width is restored to a more tolerable level , resulting in a cleaner idle and an easier transition to tune from idle to off idle.

Pin 56 on the Memcal is the cylinder select pin , depending on what the voltage is at on pin 56 it controls what fuel mode is selected.

There is a chart somewhere on this site , I think by 1Project2Many , that describes what fueling mode is selected by what voltage is seen on pin 56. I will try to search it out if I get a minute.

Hope this helps.

TOM

Is it that the pulse width remains the same, yet the net effect by going from 2nd DRP to 4th DRP is that there is less fuel per unit time thus yielding a leaner (cleaner) idle mixture to the engine? Don't have a clue about the electronics on the Memcal. Will look for something about it by 1Project2Many on this site. Don't understand the Memcal voltage dividers and if they are being sampled by what?

rsicard
01-25-2015, 06:42 PM
we dont veiw voltages but the resistance withen the netres chip that changes the voltage on the pins.TBI to pfi v8 actually looks like it needs a couple of mods with resisters to be factory correct. anyone care to measure the resistance of the pins above on a TBI memcal to see if it has the 7.5K between the 2 pins of the v8 memcal setup
http://pcmhacking.net/forums/download/file.php?id=3491

Thanks much for the diagram. Don't understand the purpose for the resistors in the Memcal. Will try to measure the resistance between the two pins on the Memcal. Heard something about the Memcal providing the limp home function of the ECU.

rsicard
01-25-2015, 08:38 PM
With the injectors firing every 2nd DRP (TBI mode) the Pulse width of the now 8 injectors (especially if you upgraded to the 29#/hr units) becomes very low. This is a result of the PCM commanding an injector pulse every 2nd DRP and essentially overfueling at idle and part throttle. Once the fueling is expanded to an injector pulse once every 4th DRP the injector pulse width is restored to a more tolerable level , resulting in a cleaner idle and an easier transition to tune from idle to off idle.

Pin 56 on the Memcal is the cylinder select pin , depending on what the voltage is at on pin 56 it controls what fuel mode is selected.

There is a chart somewhere on this site , I think by 1Project2Many , that describes what fueling mode is selected by what voltage is seen on pin 56. I will try to search it out if I get a minute.

Hope this helps.

TOM

Switching from the 2nd DRP to the 4th DRP should lean out both the on-idle and off-idle operation of the engine. Is this correct? Please advise. Thanks.

rsicard
01-26-2015, 10:17 PM
Forget my last post. I understand what is going on.

rsicard
01-27-2015, 12:36 AM
Mod'd the 16197427 ECU. Put jumps across the two current sense resistors. Also put a jumper on the Memcal per the photo from HP tuners. Installed the ECU in the Suburban and started it up. Wow does it run shitty. Shut down the truck, removed the ECU, opened it up and removed the Memcal jumper, re-installed it in the Suburban. Ah, back to running smooth. Don't know the pin layout of the Memcal so I will stay away from jumpering it for now. Set up TunerPro RT to record BLM values at idle and off idle. Open loop at idle, it fills the BLM cells with 128. Set up TP to record off idle BLMs. Ran the Suburban for several miles to warm it up, varied the speed, RPMs, gears to fill in as much of the off idle BLM cells as possible. Then came back and parked at the house. Went back to idle BLM map, varied throttle to fill in as much BLM cells as possible. Captured all with MS Excel spreadsheet.

rsicard
02-01-2015, 08:24 PM
we dont veiw voltages but the resistance withen the netres chip that changes the voltage on the pins.TBI to pfi v8 actually looks like it needs a couple of mods with resisters to be factory correct. anyone care to measure the resistance of the pins above on a TBI memcal to see if it has the 7.5K between the 2 pins of the v8 memcal setup
http://pcmhacking.net/forums/download/file.php?id=3491

Don't understand HOW netres chip voltage dividers are converted to discriminate 2nd or 4th Distributor Reference Pulses. Which two pins does the netres resistance need to be measured. Need a memcal pin layout reference to start with to be certain where to measure.

dave w
02-01-2015, 09:06 PM
The only Memcal information I have is for the '7727, '7730, & '7749 ECM I downloaded from Thridgen.org years ago. See attached pic. I DO NOT KNOW if the '7427 Memcal is exactly same? I'm not sure it's a good idea to post the pic of a different Memcal? I strongly suspect that GM would not re-invent the wheel when it came time to design the '7427 Memcal. It's likely GM would leverage / re-purpose a Memcal it already has / had in production for the '7427 Memcal with maybe a different component (limp home mode) on the Memcal for TBI?

dave w

1project2many
02-01-2015, 09:53 PM
we dont veiw voltages but the resistance withen the netres chip that changes the voltage on the pins.TBI to pfi v8 actually looks like it needs a couple of mods with resisters to be factory correct. anyone care to measure the resistance of the pins above on a TBI memcal to see if it has the 7.5K between the 2 pins of the v8 memcal setup
http://pcmhacking.net/forums/download/file.php?id=3491

I have made a series of measurements including TBI memcals and posted the results. TBI memcals show 7.5k between the two pins.
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?454-What-If-8D-(1227727-ECM)-for-TBI&p=3374&viewfull=1#post3374

The images above are for specific chips in the memcal. Those chips are connected to numbered pins on the memcal. Understanding how the ecm uses voltage on pin 56 to determine fueling mode involves studying the ecm schematics and / or having access to GM documentation. It may be a distraction if the goal is simply to make your engine run well.

Here is some work done by Cliff Harris which shows the memcal pinouts which correspond to the specific chip in the pictures above. Cliff's work has been very beneficial to this hobby. Notice how pins 53, 56, and 56 work together to provide the desired voltage for fueling mode select.

http://www.misterpeachy.com/VettePics/MEMCAL-ECM.pdf

95GMC_sierra
03-01-2015, 03:52 AM
Gents,

I am doing a similar conversion on a 454 and the edelbrock chip worked OK but high end performance was bad and ran lean at high RPM's Since the original TBI to MPFI conversion I have rebuilt the motor with significant changes and could not get it to run decent at all. I then came to this forum and was directed to the memcal jumper and PCM resistor shorting solutions and I did my homework on them. As I understand them...


Memcal jumpers

he memcal changes the threshold voltage on a comparator chip within the PCM which changes the DRP to injector bank firing number. Once this memcal mod change is done, the base pulsewidth at idle and battery voltage at idle vs pulsewidth adjustments are needed to compensate for the halving of the injector firing per cycle. I was told this is the best way to use the bank fire application since it insure a better mixture at idle, and prevents the changing of the firing sequence at idle that occurs in the TBI mode.

current sense resistor shorting

The current sense resistors are tied to ground on the low voltage side of the driver switch FET in series with the injectors and the injector drivers. The jumpering of the current sense resistor adds about 600 Milliamps of drive current at 12 volts and about 750 milliamps of drive current to the injector driver circuit at 14 volts by reducing the overall circuit series resistance by about a 1/2 ohm. The low impedance peak/hold TBI injectors are about 1.5 ohms each and the bank of 4 saturated high impedance (16 ohms each with 4 in parallel) injectors presents about 4 ohms to the driver circuit. The ability of the saturated injectors to turn on consistently and rapidly is a function of the drive current and the shorting of the sense resistor adds additional current to insure a rapid and repeatable turn on time of the saturated injectors coil. The current sense resistor shorted enables the injector coils to transition to fully open with less voltage drop/heat developed across the injector coil. The rapid saturation and shorter/crisper/faster switching time of the coil alters the actual pulsewidth (vs. commanded Pulsewidth) of the injector fuel pulse which requires initial tuning to compensate. I used an oscilloscope and a clip on current probe to analyze the current waveforms through the injectors with and without the sense resistors shorted and the shorted resistors were firing repeatably with a consistent rise time versus voltage. With the current sense resistors installed n(stock condition), the leading edge of the current pulse to the 4 injectors was slow and inconsistent, and varying pulse to pulse. The varying leading edge and "tearing" of the current injector pulse waveform means the coils were not opening reliably and repeat-ably.

I endorse the shorted current resistors and the associated retune required after viewing the current pulses on the O-scope.

I am returning to tuning this engine now and will keep you all up to date on the results. 1995 GMC 454 (30/100ths over (460 ci)), 7427 PCM with $31 mask, edelbrock MPFI with 36 lb pico injectors, edelbrock performer RPM heads, Thorley tri-wye headers and 3 inch single exhaust.

john

JeepsAndGuns
03-01-2015, 04:50 PM
Nice info. Glad I did the memcal and resistor mods when I did my conversion.

dave w
03-01-2015, 08:24 PM
Nice info. Glad I did the memcal and resistor mods when I did my conversion.

What he said X2!

dave w

rsicard
03-02-2015, 02:40 AM
Really enjoy reading the post by 95GMC_sierra. It is very interesting. Have put my 454 suburban TBI to PFI Edelbrock conversion on the back burner. Right now concentrating on the 1995 Chevrolet C1500 pickup with 350 V8 to be swapped out for 350 Vortec with 454 throttle body. May just end up putting higher pressure capable in-tank fuel pump and use 94-95 TBI two original refurbished injectors. Then tune 16197427 ECU for this combination. Just need the appropriate TBI fuel regulator spring for the higher pressure.

rsicard
11-16-2015, 01:13 AM
Gentlemen:

Would like to resolve the TBI to MPFI (batch) injection situation wherein jumpering from 2nd DRP to 4th DRP. Going back to March of 2013 the following was posted:

"Mod'd the 16197427 ECU. Put jumps across the two current sense resistors. Also put a jumper on the Memcal per the photo from HP tuners. Installed the ECU in the Suburban and started it up. Wow does it run shitty. Shut down the truck, removed the ECU, opened it up and removed the Memcal jumper, re-installed it in the Suburban. Ah, back to running smooth. Don't know the pin layout of the Memcal so I will stay away from jumpering it for now. Set up TunerPro RT to record BLM values at idle and off idle. Open loop at idle, it fills the BLM cells with 128. Set up TP to record off idle BLMs. Ran the Suburban for several miles to warm it up, varied the speed, RPMs, gears to fill in as much of the off idle BLM cells as possible. Then came back and parked at the house. Went back to idle BLM map, varied throttle to fill in as much BLM cells as possible. Captured all with MS Excel spreadsheet."

Getting better at tuning GM TBI 7427 ECMs. Trying to reason what happened when going from 2nd DRP to 4th DRP. Wow dId it run shitty. Must have been too lean? Still trying to figure out why it would run lean.

Any ideas you fellows? Please advise. Thanks.

Rolly

dave w
11-16-2015, 02:02 AM
I've done a couple MPFI conversions, admittedly with SBC's, using the Memcal jumper. I also removed the sense resistors inside the PCM and installed solid wire were there resistors used to be installed.

Maybe the attached .pdf files will help you set up the .bin file for MPFI? I converted the excel spreadsheet I used to modify the .bin files into .pdf files.

dave w

rsicard
11-16-2015, 07:13 AM
Dave:

When you converted to MPFI (batch fire) from TBI and installed the jumper of the MEMCAL, how much change, in engine running quality and, did you have to make to the off idle fuel map? The way it happened for me is that the engine ran rough. Did not have an AFR setup so don't know what happened. Will repeat with AFR setup to get clue as to what is happening. Any experience that can be shared would be greatly appreciated. Thanks for your response.

Rolly

dave w
11-16-2015, 08:43 AM
I use an Excel spreadsheet to "Crunch" the data log to correct the AFR's, see attached.

I went "All In"; I modified the memcal, .bin file, and PCM resistors before I started the engine for the first time. I then went to work on the tune immediately after the initial start up.

dave w

rsicard
11-17-2015, 01:38 AM
Dave:

1) Trying to understand the MPFI Definitions v4_0x and how to interpret or make sense of them.
2) When going from 2nd DRP to 4th DRP with the same VE fuel map, that should yield half the fuel to the engine thus a lean mixture. Or, is there a compensating factor hidden somewhere, wherein VE map fueling remains the same?
3) Is the MEMCAL almost totally for limp home mode?
4) When you went from 2nd DRP to 4th DRP on 350 engines, was there something else significant to VE map that changed?

Please advise. Thanks.

Rolly

rsicard
11-17-2015, 01:48 AM
Dave:

When going from 2nd DRP to 4th DRP on the SBC engines, was it necessary to adjust fuel pressure or change injectors to a different size? Still seems like it would try to run very lean if the jumpers to MEMCAL and resistors WERE the only change. VE fuel map change? Any other changes?

Please advise. Thanks.

Rolly

dave w
11-17-2015, 02:12 AM
Dave:

When going from 2nd DRP to 4th DRP on the SBC engines, was it necessary to adjust fuel pressure or change injectors to a different size? Still seems like it would try to run very lean if the jumpers to MEMCAL and resistors WERE the only change. VE fuel map change? Any other changes?

Please advise. Thanks.

Rolly

I modified the .bin file (CHIP) for MPFI, installed the Memcal Jumper, removed the sense resistors and installed wire were the resistors were.

Maybe you can post the .bin file you modified for MPFI? I'm wondering if maybe there is something missing / not modified in your .bin file?

dave w

rsicard
11-17-2015, 04:27 AM
Dave:

The most important question is, WHAT in the .bin file was changed for MPFI?
Attached is my binary file for 1995 C1500 350 TBI 7427 0D BJYM. Found the constants for MPFI and TBI lb/hr fueling.
How is the appropriate on (MPFI) selected? Is this done with the FLAGS section, see attached?

dave w
11-17-2015, 07:21 AM
It appears to me the posted .bin file has not been set up for MPFI. Maybe this is not the .bin file you modified for MPFI?

My previous post, with the .pdf files, outlines which Flags, Constants, and Tables in the .bin file must be modified for MPFI.

I think you need to do some homework modifying your .bin file.:thumbsup:

dave w

1BadAction
11-17-2015, 07:09 PM
I went "All In"; I modified the memcal, .bin file, and PCM resistors before I started the engine for the first time. I then went to work on the tune immediately after the initial start up.

dave w

I agree brother, not like you can easily (mechanically) go back to TBI anyways, I don't see why anyone would want to play "just the tip" with this particular conversion. I was going to get a second computer and memcal to do this myself, but then after a few minutes of thinking about it, it hit me... WHY? If I have the kinda time it takes to go back to the TBI intake, then I'll have the truck parked and enough time to convert the ECM back also. Hell the ECM changes are the fastest out of the whole ordeal.

Watching this thread myself, I have about 90% of what it takes to do the conversion on my Suburban. Just need to find the proper RP/Mercruiser injectors and a few other chicken shit items so I can get this thing back together in a timely manner. I hate letting a vehicle sit an extended period of time.

rsicard
11-18-2015, 02:41 AM
Dave:

That attached jpeg file has greatly added to an understanding of the conversion. Kept wondering what that table was keyed to. Now I know. Enlightening stuff. Thanks ever so much.

Rolly

rsicard
11-18-2015, 04:54 AM
It appears to me the posted .bin file has not been set up for MPFI. Maybe this is not the .bin file you modified for MPFI?

My previous post, with the .pdf files, outlines which Flags, Constants, and Tables in the .bin file must be modified for MPFI.

I think you need to do some homework modifying your .bin file.:thumbsup:



dave w

Dave:

In your attached JPEG file, there are five changes to the FLAGS. Is this the complete extent of the changes that need to be made? What was the table formed from? Was it from the HP Tuners fellow? Please advise. Thanks.

1project2many
11-18-2015, 05:04 AM
Watching this thread myself, I have about 90% of what it takes to do the conversion on my Suburban. Just need to find the proper RP/Mercruiser injectors and a few other chicken shit items so I can get this thing back together in a timely manner. I hate letting a vehicle sit an extended period of time.

Not to drag this too far OT, but if you have Keihin injectors I've posted some flow info.

rsicard
11-18-2015, 06:45 AM
It appears to me the posted .bin file has not been set up for MPFI. Maybe this is not the .bin file you modified for MPFI?

My previous post, with the .pdf files, outlines which Flags, Constants, and Tables in the .bin file must be modified for MPFI.

I think you need to do some homework modifying your .bin file.:thumbsup:

dave w

Dave:


In your attached JPEG file, there are five changes to the FLAGS. Is this the complete extent of the changes that need to be made? What was the table formed from? Was it from the HP Tuners fellow? Please advise. Thanks.

dave w
11-18-2015, 07:11 AM
Dave:


In your attached JPEG file, there are five changes to the FLAGS. Is this the complete extent of the changes that need to be made? What was the table formed from? Was it from the HP Tuners fellow? Please advise. Thanks.

There are three types of parameters; Constants, Flags and Tables.
You will also need to make changes the Constants and Tables. I've previously posted .pdf files that show what Constants and Tables need to be changed.

The MPFI conversion information was first posted on a HP Tuners website.

Do you need help making the MPFI changes to your .bin file (CHIP)? Setting up the .bin file is a good first step. Ultimately, you will need to "Tune" the CHIP using data logs.

dave w

rsicard
11-18-2015, 07:01 PM
There are three types of parameters; Constants, Flags and Tables.
You will also need to make changes the Constants and Tables. I've previously posted .pdf files that show what Constants and Tables need to be changed.

The MPFI conversion information was first posted on a HP Tuners website.

Do you need help making the MPFI changes to your .bin file (CHIP)? Setting up the .bin file is a good first step. Ultimately, you will need to "Tune" the CHIP using data logs.

dave w

Dave:

Thanks much for the response. Now that it is better understood, I will attempt to change the .bin file using the three posted .pdf tables. Will start with original 454 .bin file and modify from there.

Rolly

rsicard
11-18-2015, 07:14 PM
Dave:

Have you used this process in the past? Has it worked sucessfully other than having to tune the VE fuel map? Please advise. Thanks.

dave w
11-19-2015, 03:13 AM
Dave:

Have you used this process in the past? Has it worked sucessfully other than having to tune the VE fuel map? Please advise. Thanks.

Yes, I've successfully used this process in the past. Tuning can include changing some of the injector values seen in the spreadsheet.

Overall, this process can extremely challenging for a beginner!

dave w

rsicard
11-19-2015, 04:44 AM
Yes, I've successfully used this process in the past. Tuning can include changing some of the injector values seen in the spreadsheet.

Overall, this process can extremely challenging for a beginner!

dave w

Dave:

Thanks much for the reply. At first blush, changing constants, flags does not appear to be that difficult. The aspect that is not understood is "...Tuning can include changing some of the injector values seen in the spreadsheet..." Hard to relate to that statement. Please expand on same.

Regards,

Rolly

rsicard
11-19-2015, 11:06 PM
Dave:

Please expand on "Tuning can include changing some of the injector values seen in the spreadsheet". Which injector values may have to be changed?

dave w
11-20-2015, 12:08 AM
Dave:

Please expand on "Tuning can include changing some of the injector values seen in the spreadsheet". Which injector values may have to be changed?

Injector Flows: See attached screen shot of the previously posted spreadsheet / .pdf files.:thumbsup:

dave w

rsicard
11-22-2015, 07:05 AM
Injector Flows: See attached screen shot of the previously posted spreadsheet / .pdf files.:thumbsup:

dave w

Dave:

After looking at your .PDF files and looking at binaries in TunerPro RT, the PDF files have a Constant column, whereas TunerPro has Scalars, Flags and Tables. Don't understand the PDF file with the table labeled with Constants. At present, my 7.4L big block 16197427 is running the Edelbrock TBI to MPFI binary from their conversion chip. Attached us the Edelbrock binary. Is there a better association tables?

Rolly

rsicard
11-22-2015, 07:08 AM
Injector Flows: See attached screen shot of the previously posted spreadsheet / .pdf files.:thumbsup:

dave w

Dave:


After looking at your .PDF files and looking at binaries in TunerPro RT, the PDF files have a Constant column, whereas TunerPro has Scalars, Flags and Tables. Don't understand the PDF file with the table labeled with Constants. At present, my 7.4L big block 16197427 is running the Edelbrock TBI to MPFI binary from their conversion chip. Attached us the Edelbrock binary. Is there a better association tables?


Rolly, Ooops forgot the attachment.

rsicard
11-22-2015, 07:19 AM
How is the idle quality with your setup ? I wasn't able to stabilize the idle and have it be respectable with my 502 setup until I went to PFI mode with the '7427. You didn't mention camshaft so that might be a difference.

Your setup is very similar to mine before I went with the 502 , my original 454 was also bored and stroked to 489 , although it wore first a set of Vortec heads then a set of AFR heads and a few different cams .

TOM

TOM: Do you have a binary file for 489 or 502 big block that works in a 16197427 ECU? Did you do the upgrades to Edelbrock TBI to MPFI injection? Please advise. Thanks.

Rolly

1project2many
11-22-2015, 07:50 AM
Don't understand the PDF file with the table labeled with Constants.

Rolly... You're over thinking this!


There are three types of parameters; Constants, Flags and Tables.

TunerPro has Scalars, Flags and Tables.

A scalar, by any other name, still does the same job.

rsicard
11-22-2015, 07:01 PM
Rolly... You're over thinking this!




A scalar, by any other name, still does the same job.

Understand. The description in the LH column is different than what is presented in TunerPro for the four letter code in the 16197427 ECU. It is really difficult to get the confidence that performing the change in the binary will yield the appropriate binary for the MPFI (batch fire mode) in the 489 Big Block. There must be significant variable(s) for selecting going from TBI to MPFI. Have not yet seen these significant variables. There is one variable that describes CID for one cylinder. When multiplying by 8 cylinders, the total displacement does not work out. Hard to build confidence.

dave w
11-22-2015, 08:03 PM
I think the Edelbrock binary (.bin) file is not for the 16197427 computer, it's only 32K in size? The 16197427 .bin file is 64K in size. Can you post the definition file (.xdf) you are using with the Edelbrock .bin file?

The MPFI conversion is not easy for a beginner. Generally, the MPFI conversion is not the first ever experience someone starts off with. Generally, a beginner will start off with a completely stock or nearly stock engine with a completely stock binary (.bin) to learn TunerPro and learn the parameters of the .bin file. The learning curve you have set out for yourself, by choosing to do a MPFI conversion as your first .bin has put you on an extremely steep or nearly vertical uphill learning curve.

Myself and other members here at gearhead-efi.com can provide compen$ated help if you would like to go that route? Maybe it would be a good plan for you to get the help of a "hired gun" to get you up to speed and help you build confidence?

dave w

1project2many
11-22-2015, 10:56 PM
Understand. The description in the LH column is different than what is presented in TunerPro for the four letter code in the 16197427 ECU. It is really difficult to get the confidence that performing the change in the binary will yield the appropriate binary for the MPFI (batch fire mode) in the 489 Big Block.

I get that. GM never released the 7427 with PFI. Even the Edelbrock calibrations I've seen are not configured exactly the same as GM typically did with PFI swaps. What we talk about here is a combination of information from several sources that attempts to make the swap in the way we think GM would do it. This is not a road frequently travelled and over the years the path has varied as well as the results. Unlike Avionics, there is no program here to ensure you are not taking a risk before you are allowed out into the world. It's ok, though. If something goes wrong with the car you can pull it over and figure out what happened. ;)


There must be significant variable(s) for selecting going from TBI to MPFI. Have not yet seen these significant variables.
I'm not sure what you're looking for. There is no single value that makes the switch work. A successful conversion involves changing multiple values that work together to provide correct fuel in all driving conditions. The information Dave provided gives you the best starting point you will get.


There is one variable that describes CID for one cylinder. When multiplying by 8 cylinders, the total displacement does not work out.
Huh??? Stock BBC cal value is 56.66. 56.66 * 8 is 453.28. Actual displacement is 453.96. How much closer does the value need to be? Maybe you are expecting a level of precision from the tune and the ecm that really aren't there??

As far as changes related to injector strategy you will find that individual cell-by-cell tuning may be required after switching to "PFI Mode." Although the ecm calculates the correct amount of fuel to deliver based on calculated airflow and the number of injection pulses per revolution, it is not able to account for changes that occur because the manifold is not fuel soaked, because fuel is delivered at the valve, because response time during acceleration and deceleration change with the location of the injectors. When moving from four or two pulses to one, you might find that incorrect voltage compensation values meant to adjust desired "on" time affect driveablility in a dramatic way. This is another value the ecm cannot fix on its own. Additionally, you may need to do a "sanity check" on the values Dave W has posted to ensure they will work for your engine configuration. Watching the scan tool, looking at IPW and other related values is critical to help diagnose what happened.

FWIW, one of the best and most talented "ecm hacker" type guys I knew was in Avionics. Although he spent many, many hours teaching himself code he also had an advantage over all of us trying to decipher GM code back then. Because he had access to Motorola documentation, he found that many of the tech sheets for Motorola chips and circuits designed for automotive use came with example computer code. Quite often that code and the circuit matched GM equipment very closely. Where many of us had to work with dealership repair technician service literature and do our best to RE the circuits and the code, this individual had access to insider notes from the guys who designed and often built the parts GM was using. Maybe none of that information is available today but if I had access to that library I'd be searching for anything related to GM ecm's.

rsicard
11-22-2015, 11:17 PM
I think the Edelbrock binary (.bin) file is not for the 16197427 computer, it's only 32K in size? The 16197427 .bin file is 64K in size. Can you post the definition file (.xdf) you are using with the Edelbrock .bin file?

The MPFI conversion is not easy for a beginner. Generally, the MPFI conversion is not the first ever experience someone starts off with. Generally, a beginner will start off with a completely stock or nearly stock engine with a completely stock binary (.bin) to learn TunerPro and learn the parameters of the .bin file. The learning curve you have set out for yourself, by choosing to do a MPFI conversion as your first .bin has put you on an extremely steep or nearly vertical uphill learning curve.

Myself and other members here at gearhead-efi.com can provide compen$ated help if you would like to go that route? Maybe it would be a good plan for you to get the help of a "hired gun" to get you up to speed and help you build confidence?

dave w

Yes I have limited experience. Right now a converted 350 Vortec with 454 TBI, adapter, modified 4 barrel manifold on an engine stand with somewhat tuned 7427 ECU. Using early build APU1 and 27SF512 Flash Memory Chips and Moates G1 adapter. Second, tuned 1995 350 C1500 pickup. Smoothed the VE fuel map and it runs near stoic most of the time. Also at the earliest, modified a 454 big block to 489 cuin and installed Edelbrock Intake (batch fire MPFI) and fuel pump. Have had some exposure at tuning TBI/MPFI systems. Would like to learn more about tuning with TunerPro. In post number 65, you provided a sample from the Constants variables.

What is really of concern is, from what is seen in TunerPro with either the 1994-1995 0D or 0E broadcast codes, the sample injector FLOW RATES in the PDF file(s) are not included in the Scalers, Flags or Tables. In the scalars portion, under engine constants, there are listings for CPI, TBI and MPFI. Yet how is MPFI Selected?

I understand that I could pay you to come up with a binary file. How much would it cost? Yet I would like to learn how to do same. It is becoming obvious that TunerPro is a high level front end wherein changes to one variable will change an associated Byte or Word in the Binary file. To me, it is a matter of interpretation of the terms of reference being used when speaking of variables in TunerPro.

I just received a breakout board for the purpose of bench testing the ECU to see what happenes when changing certain variables in TunerPro. Already have the ECU connectors, with pig tails, for the 7427. Now it is a matter of connecting the pigtails to the breakout. Already have purchased MegaSquirt Stimulator Kit which should be here next week. Then assemble same. Then connect the breakout to the Stimulator and ECU. Am experienced in electronics (38+ years in Aviation Electronics) and this should not be that hard to do.

dave w
11-23-2015, 12:09 AM
I think the attached .bin file will be EXTREMELY HELPFUL.:thumbsup: The attached .bin has been tested, and is in use somewhere in North America.

The original .bin file I modified for MPFI is from a very well known aftermarket EFI company. The attached .bin file requires the Memcal Jumper Modification, and the solid wire modification to the sense resistors inside the PCM!!!

Standard Disclaimer; Use at your own risk.

dave w

rsicard
11-23-2015, 02:29 AM
I think the attached .bin file will be EXTREMELY HELPFUL.:thumbsup: The attached .bin has been tested, and is in use somewhere in North America.

The original .bin file I modified for MPFI is from a very well known aftermarket EFI company. The attached .bin file requires the Memcal Jumper Modification, and the solid wire modification to the sense resistors inside the PCM!!!

Standard Disclaimer; Use at your own risk.

dave w

Dave: Thanks very much for the reply. I will try that .bin file. Not sure what the attached .JPEG file is to represent. The attached image file is what was gleaned from the MPFI Modified $31 Aftermarket 454 Chip.BIN. Don't understand the vast differences between the two.

sturgillbd
11-23-2015, 02:38 AM
Rolly,
The bin Dave posted is a $31 Mask. You need to load the $31 XDF. Different mask will show different values because the parameters are in different locations within the bin file.
Hope this helps,
Brian

dave w
11-23-2015, 03:25 AM
I've attached the $31 .xdf and $31 .adx files you need for TunerPro RT.

dave w

1project2many
11-23-2015, 03:59 AM
Rolly,
The bin Dave posted is a $31 Mask. You need to load the $31 XDF. Different mask will show different values because the parameters are in different locations within the bin file.

Yes! Maybe this helps explain some things.

Rolly, the different chip ID's you see, $31, $0E, and $0D, are identifiers for where the specific variables are arranged within the calibration. When you load an XDF, Tunerpro is instructed to treat each variable in each defined location a certain way. There will be a variable (or table) name and a conversion factor so the binary value represents a number we understand. If a .bin with the wrong mask ID is loaded then Tunerpro does not do any sanity checking. It will treat the variables as it has been instructed, giving each the predefined name and displaying the value according to the conversion formula. It could treat temperature as timing, throttle values as O2 parameters, or fuel injector size as rpm. For many this issue never comes up but unfortunately the 7427 and sister pcm's share three commonly used mask files.

rsicard
11-23-2015, 06:15 AM
Yes! Maybe this helps explain some things.

Rolly, the different chip ID's you see, $31, $0E, and $0D, are identifiers for where the specific variables are arranged within the calibration. When you load an XDF, Tunerpro is instructed to treat each variable in each defined location a certain way. There will be a variable (or table) name and a conversion factor so the binary value represents a number we understand. If a .bin with the wrong mask ID is loaded then Tunerpro does not do any sanity checking. It will treat the variables as it has been instructed, giving each the predefined name and displaying the value according to the conversion formula. It could treat temperature as timing, throttle values as O2 parameters, or fuel injector size as rpm. For many this issue never comes up but unfortunately the 7427 and sister pcm's share three commonly used mask files.

Man, cannot thank you enough for your education on chip ID's and XDF files. Did not give this aspect any thought. Now it is burned in my memory. Must keep in mind that XDF files decode the binary values. Is the mask ID available in the .bin even if the .bin and XDF files are not properly associated? Any other tips like this that can be passed on would be greatly appreciated.

Rolly

rsicard
11-23-2015, 06:45 AM
You guys are awesome. Thanks for the reply.

Rolly

rsicard
11-23-2015, 06:46 AM
Again, you guys are AWESOME! Thank VERY much for the attached files. Exactly what was needed

Rolly

rsicard
11-23-2015, 06:47 AM
Rolly,
The bin Dave posted is a $31 Mask. You need to load the $31 XDF. Different mask will show different values because the parameters are in different locations within the bin file.
Hope this helps,
Brian

You guys as AWESOME. Thanks for the reply.

Rolly

rsicard
11-23-2015, 06:49 AM
I've attached the $31 .xdf and $31 .adx files you need for TunerPro RT.

dave w

Again, you guys are AWESOME. Thank ever so much for the attached files. Lesson learned.

Rolly

rsicard
11-23-2015, 06:59 AM
I've attached the $31 .xdf and $31 .adx files you need for TunerPro RT.

dave w

Dave: Now I have confidence with the binary file and attached XDF and ADX files. Many thanks to you and the other fellows that chimed in. Attached is a graphic of the Injector Fuel Flow Scalars. The values look VERY reasonable. Thanks again.

Rolly

1project2many
11-23-2015, 07:05 AM
Is the mask ID available in the .bin even if the .bin and XDF files are not properly associated?

Yes, mostly. You can view it in the $31 XDF that Dave W uploaded and in the other XDF's with the filename beginning Advanced..." With the .bin loaded look at Scalars -> Mask ID. There are some exceptions but if you stick to known files and confirm the correct mask each time, you should have no problems.

rsicard
11-23-2015, 11:18 PM
Hey Guys, need help in modifying XDF file for $31. Would like to expand columns from 11 to 16. See attached image file. Also made a test drive to record BLMs. See attached .xls file. Rick in some spots, lean in others. I can modify the VE fuel map to make these spots closer to 128. Any help with XDF file would be greatly appreciated.

Rolly

1project2many
11-23-2015, 11:26 PM
Hmmm....

You can tell the XDF that there are 16 columns and that will make TunerPro display 16 columns. But just like using the wrong definition, if there are only 11 columns in the .bin then changing the definition will only display other values incorrectly. It is possible to change the code in the chip so there are more values but it usually isn't a trivial task.

rsicard
11-24-2015, 03:35 AM
Hmmm....

You can tell the XDF that there are 16 columns and that will make TunerPro display 16 columns. But just like using the wrong definition, if there are only 11 columns in the .bin then changing the definition will only display other values incorrectly. It is possible to change the code in the chip so there are more values but it usually isn't a trivial task.

Thanks much for the reply. Don't want to mess with the chip except when using TunerPro.

Rolly

rsicard
11-24-2015, 07:43 AM
I've attached the $31 .xdf and $31 .adx files you need for TunerPro RT.

dave w

Dave: Thanks again. The 1994 Suburban with big block 489 cuin Edelbrock MPFI conversion is running very well. It needs a little tweaking for some of the rich and lean conditions yet they are not that bad. Thanks to all of you fellows for all your help.

Rolly

GearX
06-05-2017, 08:04 AM
any updates on this one? have you managed to finish the tuning?

mike454
07-19-2019, 04:47 PM
hello rsicard,
Did you finish the tune on the mpfi big block? Just wondering how it turned out.
Did you do the conversion on the ecm? Did you end up doing the jumper mod, or the sense resistor mod?


I too have a Edelbrock conversion, heads,cam,mpfi intake, chip, that was just bought and installed, as it came,back in 09....I ended up with it thru trade
it runs, ok I guess, but knowing how it should run, there is quite a bit left on the table.
I'm tackling the learning curve on some easier stuff first, before I take the plunge.
Just reading and gathering info.


Mike454