350 Vortec wi th 454 TBI running pig rich

**brian617** · 03-24-2015

rsicard,

With all due respect, stop posting and start searching and reading. You have started so many post, yet not followed through with anyones advice. Go here http://www.gearhead-efi.com/Fuel-Inj...g-Error-Codes! and read all the sticky links. When your'e done, read them all again. Same here http://www.gearhead-efi.com/Fuel-Inj...-quot-FAQ-quot

There are hour after hour of great reading information in those links.

**rsicard** · 03-24-2015

Originally Posted by brian617

rsicard,

With all due respect, stop posting and start searching and reading. You have started so many post, yet not followed through with anyones advice. Go here http://www.gearhead-efi.com/Fuel-Inj...g-Error-Codes! and read all the sticky links. When your'e done, read them all again. Same here http://www.gearhead-efi.com/Fuel-Inj...-quot-FAQ-quot

There are hour after hour of great reading information in those links.

Brian617: Understand what you are saying. Have read at least 1/2 of what you have provided links for. Have spent many an hour reading through the materials. Still have open questions. Understand if the guys on here are getting tired of seeing my name. But after not achieving an objective, there is much more to do. I will go off and read the other link you posted and gather a compendium of what was posted. Maybe it will provide more insight. So the responses have come in little bits and pieces that do not form a bigger complete picture in the mind. Maybe forming a compendium of the other link will do the job. Every person uses their own terminology. Lots of TLAs. Again, the reader does not know what is in the writers mind unless the writer spells it all out the picture in his mind. Find this to be a very common problem leading to misunderstandings and taking the wrong path forward. See this every day.

Getting really tired and frustrated of seemly getting NOWHERE. Only on about the 7th or 8th run on the engine stand. Got a whole collection of injectors and regulator springs. No positive way to measure their performance. Don't have automated test equipment to test the ECMs for quality of performance. Worked in engineering on the B2 bomber 750 shaft Horse Power Aux Power Unit (APU) Electronics Control Unit (ECU). Characterized the ECU and formed Lotus 123 spread sheet of input and outputs with limits and tested the Line Replaceable Units (LRUs) in 45 seconds with embedded 8088 microprocessor on Std buss rack. Worked like gang busters. Lots of experience in Aerospace Electronics.

**DOCBAWRENCHTURNER** · 03-25-2015

rsicard- I have been in the same boat with the engine running pig rich. the BPW is in the scalars. I believe that there is a calculator/excel file somewhere to help with this. I ended up telling the PCM that my injectors are larger than what it has in it due to my increased fuel pressure. Also the number your changing is a pcm based number, it will be somewhere around 10 and probably a decimal. You also need to make sure that you IAC is set to where it needs to be (there is a write up about this). I believe Mark said he aimed for ~20 counts.

edit... I understand your frustration that after 7-8 tries you haven't been able to see any progress, keep in mind that most people here have tried 10-20 times a day. There is a method to this madness, but the learning curve is steep. I have a 96 Vortec engine in a 95 pickup running TBI, similar issues, but we all have to work one step at a time.

**rsicard** · 03-25-2015

Originally Posted by DOCBAWRENCHTURNER

rsicard- I have been in the same boat with the engine running pig rich. the BPW is in the scalars. I believe that there is a calculator/excel file somewhere to help with this. I ended up telling the PCM that my injectors are larger than what it has in it due to my increased fuel pressure. Also the number your changing is a pcm based number, it will be somewhere around 10 and probably a decimal. You also need to make sure that you IAC is set to where it needs to be (there is a write up about this). I believe Mark said he aimed for ~20 counts.

edit... I understand your frustration that after 7-8 tries you haven't been able to see any progress, keep in mind that most people here have tried 10-20 times a day. There is a method to this madness, but the learning curve is steep. I have a 96 Vortec engine in a 95 pickup running TBI, similar issues, but we all have to work one step at a time.

DOCBAWRENCHTURNER: Really appreciate your post. I am retired and getting older by the day. Will keep looking for BPW adjustments in TunerPro. Tried several regulator springs and the lowest pressure that can be achieved is 12-14 psi. Will try the 7.4L injectors and bump up the fuel pressure to see what happens. Thinking about putting in an external fuel regulator, referenced to manifold vacuum, to adjust pressure easily. If I can get SOMEWHERE close to where it should be, then will tune VE and use Dave W. spreadsheet stuff to get closer to 14.7 AFR.

Sure would be nice to have a checklist to go by for setting these things up. Just got done forming another lengthy document of the links provided by Brian617. Have seen this stuff all before. Still have open questions. Likely, people like Dave W. are tired of responding to my questions. Sure would like to get one of them on the telephone and form a checklist in my brain. Then I would write it down. Can always bite the bullet and spend multi-thousands of dollars for a self learning sequential port fuel injection system. But I am retired and on a fixed income. Chose a 1995 pickup because parts are cheaper than the newer models. Want this one to last until I pass on. Already have a Monster rebuilt 4L60E and latest Hughes Torque converter ready to go behind the Vortec. Now if I could only get the Vortec running properly. Spent enough money already.

**brian617** · 03-25-2015

There is no BPW constant in the 7427, only Injector Flow Rate, but as I mention before you cannot change it until you've settled on a injector/fuel pressure combo. In one of my replys I insisted you quit fumbling with different injectors and fuel pressure and just pick the combo you need for your HP requirement, even gave you the link to the injector calculator.

First, what HP number is your engine combo good for 350hp? If so 350hp with a BSFC Brake Specific Fuel Consumption of .475 at 85% IDC Injector Duty Cycle says you need 98 PPH Pounds Per Hour of fuel. Now you take you 65 PPH @ 13PSI 350 injectors and you need 30+ PSI of fuel pressure to ahcive this goal. or you could use BBC 80PPH @ 13psi injectors you need 20psi to get there. http://www.witchhunter.com/injectorcalc1.php

Once you get that set you must make the change to the Injector Flow Rate in your .BIN, but dont expect it to run great strait out of the box. This is were the changes in the VE table must be made.

**rsicard** · 03-25-2015

Originally Posted by brian617

There is no BPW constant in the 7427, only Injector Flow Rate, but as I mention before you cannot change it until you've settled on a injector/fuel pressure combo. In one of my replys I insisted you quit fumbling with different injectors and fuel pressure and just pick the combo you need for your HP requirement, even gave you the link to the injector calculator.

First, what HP number is your engine combo good for 350hp? If so 350hp with a BSFC Brake Specific Fuel Consumption of .475 at 85% IDC Injector Duty Cycle says you need 98 PPH Pounds Per Hour of fuel. Now you take you 65 PPH @ 13PSI 350 injectors and you need 30+ PSI of fuel pressure to ahcive this goal. or you could use BBC 80PPH @ 13psi injectors you need 20psi to get there. http://www.witchhunter.com/injectorcalc1.php

Once you get that set you must make the change to the Injector Flow Rate in your .BIN, but dont expect it to run great strait out of the box. This is were the changes in the VE table must be made.

Brian617: First have to fix the PIG RICH running situation. With 61 or 65 pph injectors and 12-14 psi fuel pressure, it runs Wide Band AFR 10.x:1. Kicks out black smoke it so rich. The 7.4L 30 psi injectors appear to be the way to go. The higher the pressure used with the injectors, the better the atomization of fuel. Better to use the 30 psi 7.4L '94-'95 injectors and dial in the fuel pressure to get it in the ball park of where the AFR should be. Then tune VE tables using Dave W. spreadsheet process. Suspect that the unknown MemCal I am using, may be causing the PIG RICH situation. Will use the one from my 1995 5.7L 350 engine using 16197427 ECU but will change out the Flash memory chip with a Moates adapter.

**sturgillbd** · 03-25-2015

Before we go into the bin, can you do us all a favor and take a picture of your tbi adapter? I want to see what you are using. There are some out there that are notorious for vacuum leaks. If it is the 1/4" steel plate or a thin aluminum plate, do the TBI mounting bolts protrude through it when the throttle body is mounted to it? If so, the bolts may be causing part of your issue.

**sturgillbd** · 03-25-2015

Ok... In $0D, there is simply a injector PPH setting. Open up Tuner Pro and switch to parameter category view. One screenshot below will show you the injector size setting and the another screenshot is thelocation of the VE tables. If you have the 65 PPH injectors in the TBI, set it to 65 instead of the default 61. Where you have increased your pressure you will have to calculate the new flow based on your new pressure. The idle VE table is also pictured and that is where you adjust the Idle VE. You have to learn to crawl before you learn to run. There are many documents on here and on the web that describe tuning these systems. Some describe using WinALDL for logging such as this : http://www.gmcmidwestclassics.org/We...0the%20TBI.pdf but it is for tuning a 1227747 ecm on a motorhome. The same basic principles apply for the 16197427 but the 7427 is a more complicated controller. If you switch to parameter view, Tunerpro groups the tables, scalars in a more readable format for me. When you first dive into tuning, you feel like a lost ball in high weeds. Take your time and read. Open the bin, look through the parameters. The parameters for $0D are well documented. If you put the mouse pointer over a parameter, it will have a floating window pop up with the description of what it does. Once you know what your injectors are flowing at your set pressure, put that into the injector size in PPH. I am going to attach 3 screenshots and maybe this will help you get started.

**rsicard** · 03-25-2015

Originally Posted by sturgillbd

Ok... In $0D, there is simply a injector PPH setting. Open up Tuner Pro and switch to parameter category view. One screenshot below will show you the injector size setting and the another screenshot is thelocation of the VE tables. If you have the 65 PPH injectors in the TBI, set it to 65 instead of the default 61. Where you have increased your pressure you will have to calculate the new flow based on your new pressure. The idle VE table is also pictured and that is where you adjust the Idle VE. You have to learn to crawl before you learn to run. There are many documents on here and on the web that describe tuning these systems. Some describe using WinALDL for logging such as this : http://www.gmcmidwestclassics.org/We...0the%20TBI.pdf but it is for tuning a 1227747 ecm on a motorhome. The same basic principles apply for the 16197427 but the 7427 is a more complicated controller. If you switch to parameter view, Tunerpro groups the tables, scalars in a more readable format for me. When you first dive into tuning, you feel like a lost ball in high weeds. Take your time and read. Open the bin, look through the parameters. The parameters for $0D are well documented. If you put the mouse pointer over a parameter, it will have a floating window pop up with the description of what it does. Once you know what your injectors are flowing at your set pressure, put that into the injector size in PPH. I am going to attach 3 screenshots and maybe this will help you get started.

Strugillbd: By providing images of the TunerPro screens for 7427, you are hitting the ball out of the park. Really good stuff. This is the stuff that can really be used. There are SO MANY selections in the TunerPro Constants, Flags and Tables it can easily get confusing. The way you present it with images, get right to the point clearly. A picture is worth a thousand words.

Before I can use what you have posted, with 61 or 65 pph injectors and 12-14 psi, the 350 Vortec is running PIG RICH Wide Band AFR=10.x:1. Is there an indicator when running in Limp Home Mode? I suspect that the appropriate MemCal must be used. I will have to get one out of the 1995 Chev C1500 pickup and use it. Perhaps that will fix the PIG RICH situation. Don't know how many different MemCals there are or what effect the different one have. Giving thought to using the 7.4L injectors and adjusting fuel pressure AFTER getting the PIG RICH situation under control.

Attached is an image file of TunerPro and the constant set for TBI.