TBI guys, its time to update!
#151
Originally posted by JPrevost
You can also pass in closed loop without the emissions junk if you modify the PID routine . I can "average" anywhere from a 12 to 16 afr.
You can also pass in closed loop without the emissions junk if you modify the PID routine . I can "average" anywhere from a 12 to 16 afr.
#152
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
JP,
Hows the NOx running that lean? Im sure it wouldnt matter as much with my low compression motor. Even better is delete the cat, but possibly use the linear EGR to control the NOx if its a problem. Man would be great to get rid of the cat.
I like the idea of tweaking the PID routine to target a lower AFR. Id probably disable or limit the prop. term and O2 error params as well as the O2 window so I dont get punted out of closed loop. Also set the BLMs not to be cleared and scale them to all be in the areas that the car will be inspected at. Drive the car around for half an hour or so beforehand so the BLMs have time to settle out and it should blow a steady lean AFR.
Hows the NOx running that lean? Im sure it wouldnt matter as much with my low compression motor. Even better is delete the cat, but possibly use the linear EGR to control the NOx if its a problem. Man would be great to get rid of the cat.
I like the idea of tweaking the PID routine to target a lower AFR. Id probably disable or limit the prop. term and O2 error params as well as the O2 window so I dont get punted out of closed loop. Also set the BLMs not to be cleared and scale them to all be in the areas that the car will be inspected at. Drive the car around for half an hour or so beforehand so the BLMs have time to settle out and it should blow a steady lean AFR.
Last edited by dimented24x7; 10-29-2005 at 11:21 AM.
#153
Originally posted by dimented24x7
JP,
Hows the NOx running that lean? Im sure it wouldnt matter as much with my low compression motor. Even better is delete the cat, but possibly use the linear EGR to control the NOx if its a problem. Man would be great to get rid of the cat....
JP,
Hows the NOx running that lean? Im sure it wouldnt matter as much with my low compression motor. Even better is delete the cat, but possibly use the linear EGR to control the NOx if its a problem. Man would be great to get rid of the cat....
EDIT: Oops!, I didn't see that you were asking JP. Oh well.
Last edited by HaulnA$$; 10-29-2005 at 12:09 PM.
#154
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
The way they handle power enrich in these is really cool. Its no longer just go full rich and waste gas when the TPS is above a certain point. Instead it may not necessarily richen the AFRs, but just exit closed loop if the throttle is somewhere in between. It also doesnt enter PE right away, but rather brings the AFRs smoothly in with time and/or ammount of throttle. The PE spark is also brought in smoothly over time as teh time in PE increases. There is also a routine to estimate if the cat is overheating. It limits how lean the AFRs can go if this state exists.
The computer reverts back to the old way of quickly going full rich if you stab the throttle down to the floor or youve been flogging the car/truck.
The computer reverts back to the old way of quickly going full rich if you stab the throttle down to the floor or youve been flogging the car/truck.
#155
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Anyone know what pin is for the MAT? How about the A/C clutch control? Or better yet, pinouts for a CPI blazer would also work.
Finally got off my lazy *** and bought some connectors from rosesandwrenches and made up a short harness so I can run/test the PCM on the bench before it goes in the car. But, still missing a few things...
Finally got off my lazy *** and bought some connectors from rosesandwrenches and made up a short harness so I can run/test the PCM on the bench before it goes in the car. But, still missing a few things...
#156
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Car: 82 ElCamino, looking for a 3rd gen
Engine: 305 TPI(427SB in progress) 730 $8D
Transmission: THM350 (Getting a 4L80E soon)
Axle/Gears: 10 Bolt w/ 2.43 gears :(
Yesterday I decided to swap over from the 7730 $8D combo I've been running to the 7427 PCM $31 mask to start getting my feet wet with the new unit. I was reading that a hardware change has to be made to the netres to allow for currect PFI mode enable (idle and low loads have a very annoying surge which I assume is to the hardware change not being made). Also I can't get HaulnA$$'s fan enable to function under the $31 mask (I think I made the change at the currect address) as well put the fan relay control on E3 (which is the pin for the Tuning Valve on a 95 CPI blazer). I will attach my current Bin if anyone want to help me find my mistake on the fan control and any other obvious problems - including PFI enable. Also could someone verify that the Injector Constant is set currectly for 19Lb/Hr units.
Current bin Disclaimer ---NOT TO BE USED ON A VEHICLE OTHER THAN THE ONE OWNER BY ME---
Prom/NETRES in the PCM is a BMHM
http://www.moates.net/files/2)%20Cus...es/305BMHM.BIN
Current bin Disclaimer ---NOT TO BE USED ON A VEHICLE OTHER THAN THE ONE OWNER BY ME---
Prom/NETRES in the PCM is a BMHM
http://www.moates.net/files/2)%20Cus...es/305BMHM.BIN
Last edited by eric305TPI; 11-28-2005 at 08:58 PM.
#157
Originally posted by eric305TPI
Yesterday I decided to swap over from the 7730 $8D combo I've been running to the 7427 PCM $31 mask to start getting my feet wet with the new unit. I was reading that a hardware change has to be made to the netres to allow for currect PFI mode enable (idle and low loads have a very annoying surge which I assume is to the hardware change not being made). Also I can't get HaulnA$$'s fan enable to function under the $31 mask (I think I made the change at the currect address) as well put the fan relay control on E3 (which is the pin for the Tuning Valve on a 95 CPI blazer). I will attach my current Bin if anyone want to help me find my mistake on the fan control and any other obvious problems - including PFI enable. Also could someone verify that the Injector Constant is set currectly for 19Lb/Hr units.
Current bin Disclaimer ---NOT TO BE USED ON A VEHICLE OTHER THAN THE ONE OWNER BY ME---
Prom/NETRES in the PCM is a BMHM
http://www.moates.net/files/2)%20Cus...es/305BMHM.BIN
Yesterday I decided to swap over from the 7730 $8D combo I've been running to the 7427 PCM $31 mask to start getting my feet wet with the new unit. I was reading that a hardware change has to be made to the netres to allow for currect PFI mode enable (idle and low loads have a very annoying surge which I assume is to the hardware change not being made). Also I can't get HaulnA$$'s fan enable to function under the $31 mask (I think I made the change at the currect address) as well put the fan relay control on E3 (which is the pin for the Tuning Valve on a 95 CPI blazer). I will attach my current Bin if anyone want to help me find my mistake on the fan control and any other obvious problems - including PFI enable. Also could someone verify that the Injector Constant is set currectly for 19Lb/Hr units.
Current bin Disclaimer ---NOT TO BE USED ON A VEHICLE OTHER THAN THE ONE OWNER BY ME---
Prom/NETRES in the PCM is a BMHM
http://www.moates.net/files/2)%20Cus...es/305BMHM.BIN
#158
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Car: 82 ElCamino, looking for a 3rd gen
Engine: 305 TPI(427SB in progress) 730 $8D
Transmission: THM350 (Getting a 4L80E soon)
Axle/Gears: 10 Bolt w/ 2.43 gears :(
Hauln Can you explain what has to be done to the netres. Also thanks for noticing the bits that were misset. What exactly are you refering to when you state the injector calirations? The fan is not important right now as it is running off of a homemade controller. I need to spend a bunch of time on the disassembly and reassembly as my attempt for this did not work (disassembled file was over 2GB! when I came back and closed the dos prompt) I will learn it though.
#159
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Car: 1989 Iroc-Z
Engine: 350, ZZ4 equivalent
Transmission: Pro-Built Road Race 700R4
Axle/Gears: 3.23 Dana 44
Originally posted by dimented24x7
Anyone know what pin is for the MAT? How about the A/C clutch control? Or better yet, pinouts for a CPI blazer would also work.
Anyone know what pin is for the MAT? How about the A/C clutch control? Or better yet, pinouts for a CPI blazer would also work.
#160
Originally posted by eric305TPI
Hauln Can you explain what has to be done to the netres. Also thanks for noticing the bits that were misset. What exactly are you refering to when you state the injector calirations? The fan is not important right now as it is running off of a homemade controller. I need to spend a bunch of time on the disassembly and reassembly as my attempt for this did not work (disassembled file was over 2GB! when I came back and closed the dos prompt) I will learn it though.
Hauln Can you explain what has to be done to the netres. Also thanks for noticing the bits that were misset. What exactly are you refering to when you state the injector calirations? The fan is not important right now as it is running off of a homemade controller. I need to spend a bunch of time on the disassembly and reassembly as my attempt for this did not work (disassembled file was over 2GB! when I came back and closed the dos prompt) I will learn it though.
#161
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Originally posted by 89 Iroc Z
If your running the 16197427 ECM ($0D mask) here is the wire diagrams off GMECM http://www.diy-efi.org/gmecm/ecm_info/16197427/
If your running the 16197427 ECM ($0D mask) here is the wire diagrams off GMECM http://www.diy-efi.org/gmecm/ecm_info/16197427/
#163
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Car: 1989 Iroc-Z
Engine: 350, ZZ4 equivalent
Transmission: Pro-Built Road Race 700R4
Axle/Gears: 3.23 Dana 44
Oddly enough, none of the wire diagrams have MAT's in them. I uploaded some wire diagrams for you guys on Moates site:
16168625 PCM - 93 C1500 Pickup 4L60E - Wire Diagram
16197427 PCM - 95 C1500 Pickup 4L60E Wire Diagrams
One intresting thing I noticed is that the 16197427 PCM, $0D uses two knock sensors.
16168625 PCM - 93 C1500 Pickup 4L60E - Wire Diagram
16197427 PCM - 95 C1500 Pickup 4L60E Wire Diagrams
One intresting thing I noticed is that the 16197427 PCM, $0D uses two knock sensors.
#164
Originally posted by 89 Iroc Z
.....One intresting thing I noticed is that the 16197427 PCM, $0D uses two knock sensors.
.....One intresting thing I noticed is that the 16197427 PCM, $0D uses two knock sensors.
#167
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Do all V6 apps use the dual KS', or is it just something thats on the high performance CPI option?
#168
Originally posted by dimented24x7
Do all V6 apps use the dual KS', or is it just something thats on the high performance CPI option?
Do all V6 apps use the dual KS', or is it just something thats on the high performance CPI option?
#169
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Car: 91 Red Sled
Axle/Gears: 10bolt Richmond 3.73 Torsen
Originally posted by HaulnA$$
All of 'em, including my '95 4.3 TBI (soon to be MPFI) S-10 daily driver. My '94 C1500 TBI V-8 only has one. HTH
All of 'em, including my '95 4.3 TBI (soon to be MPFI) S-10 daily driver. My '94 C1500 TBI V-8 only has one. HTH
#170
Originally posted by JPrevost
I'm just taking a stab in the dark with this one but I have a feeling the dual knock sensors had something to do with the balance shafts in the 93+ 4.3L v6's. I can't think of any other reason to have it unless they had code that would do individual cylinder retard like the LS1's.
I'm just taking a stab in the dark with this one but I have a feeling the dual knock sensors had something to do with the balance shafts in the 93+ 4.3L v6's. I can't think of any other reason to have it unless they had code that would do individual cylinder retard like the LS1's.
#171
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Update for those of you who are using the PCMs.
Ive finally gotten to the point of making a massive dent in the side of this thing. All those thousands of uncommented lines of code in the original $0D hack where hiding a dirty little secret...
A very large, full PID idle routine with multiple derivative terms, sophisticated subroutines to construct the desired RPM, integral, proportional, and derivative terms, full learning capacity, and logic to detect saturation and integrator windup due to IAC faults. It even has a proportional control routine for the battery volts to speed the engine up and increase alternator output if the battery is draining. All of that and theres still lots of idle stuff left to be commented.
Needless to say I wasnt expecting that. I had thought it would have had something like the half-assed stock idle routine in the first TBI ECMs with some extra add-ons. Instead they ditched all the previous stuff and started over.
Gone is the method of just looking up the IAC counts, kicking down, and adding/removing steps depending on what the engine speed is. Now its all done in percentage of IAC flow to give linearity and only at the end are the actual needed IAC counts retrieved from the airflow. Not only that, but theres always some form of closed loop action and it enters closed loop idle much sooner.
It looks like a massive pain in the *** to tune but once comple it should practically think for itself.
Anyway, Ill see if I cant get something posted soon so we'll have a better idea of how it works.
Ive finally gotten to the point of making a massive dent in the side of this thing. All those thousands of uncommented lines of code in the original $0D hack where hiding a dirty little secret...
A very large, full PID idle routine with multiple derivative terms, sophisticated subroutines to construct the desired RPM, integral, proportional, and derivative terms, full learning capacity, and logic to detect saturation and integrator windup due to IAC faults. It even has a proportional control routine for the battery volts to speed the engine up and increase alternator output if the battery is draining. All of that and theres still lots of idle stuff left to be commented.
Needless to say I wasnt expecting that. I had thought it would have had something like the half-assed stock idle routine in the first TBI ECMs with some extra add-ons. Instead they ditched all the previous stuff and started over.
Gone is the method of just looking up the IAC counts, kicking down, and adding/removing steps depending on what the engine speed is. Now its all done in percentage of IAC flow to give linearity and only at the end are the actual needed IAC counts retrieved from the airflow. Not only that, but theres always some form of closed loop action and it enters closed loop idle much sooner.
It looks like a massive pain in the *** to tune but once comple it should practically think for itself.
Anyway, Ill see if I cant get something posted soon so we'll have a better idea of how it works.
#172
TPI swap done
Bringing this post back up. I know it has been a long time coming, but I finally finished the TPI setup using the $0D mask. Besides the fact that I have been busier than a one legged grape stomper, what took so long was researching all the code differences between TBI and MPFI then testing the changes on the PCM bench. I wanted it to be a painless swap and it was. It runs great. It needs just a minor amount of tuning, mostly AE and startup. It is my sons '94 C1500 305 with 160k miles and a 16196395 PCM. The truck is stock except for exhaust and all the TBI tuning I did on it. I made sure to eliminate as many variables in the swap as possible. I had the injectors (19lb. SVO's) cleaned and flowed. I used all new connectors and made up my own conversion harness, more on that later. I got a new serpentine accessory drive setup from SDPC to clear the throttle body and I ran steel braided fuel lines with AN fittings and adapters. The IAC was replaced and a new Walbro 190 was installed and I got a new throttle cable from Jim's Performance. The mechanical part was all plug and play so I will spare the details.
On the PCM/code side is where I spent the most time (the last year or so) figuring stuff out. What I ended up doing was modifying the P&H injector drivers to drive saturated injectors. I also modified the Memcal mode select for an 8 cyl. PFI setup. All the pertinant calibration data was changed to run the TPI like injector biases and offsets, select bits, etc. In the startup .bin, I deleted EGR and CCP until I get it tuned then I will add it back as well as install a MAT sensor and tune for it. As for the wiring changes, they were minimal. I had to replace the TBI injector connectors for port connectors. I ran 4 injectors off of each driver. I also had to extend the IAC and TPS wires about 10 inches and swap the TPS connector for the old style flat type vs. the round type. Thats it. It runs great and idles smoother that any other TPI I have seen. Once I get it tuned, I will make some 0 to 60 runs and post the differences. Here are some before and after pics. Enjoy!
On the PCM/code side is where I spent the most time (the last year or so) figuring stuff out. What I ended up doing was modifying the P&H injector drivers to drive saturated injectors. I also modified the Memcal mode select for an 8 cyl. PFI setup. All the pertinant calibration data was changed to run the TPI like injector biases and offsets, select bits, etc. In the startup .bin, I deleted EGR and CCP until I get it tuned then I will add it back as well as install a MAT sensor and tune for it. As for the wiring changes, they were minimal. I had to replace the TBI injector connectors for port connectors. I ran 4 injectors off of each driver. I also had to extend the IAC and TPS wires about 10 inches and swap the TPS connector for the old style flat type vs. the round type. Thats it. It runs great and idles smoother that any other TPI I have seen. Once I get it tuned, I will make some 0 to 60 runs and post the differences. Here are some before and after pics. Enjoy!
#173
That is awesome! I have been wanting to do that with my '94 c1500 for a while, But just dont have the experience to dive into the code side of it. What exactly did you have to do to the injector drivers? Have you driven it enough to notice a mpg increase? I bet it is a treat to drive!
----------
Is that TBI you where running on the 305, a BBC unit, it looks like it in the pictures?
----------
Is that TBI you where running on the 305, a BBC unit, it looks like it in the pictures?
Last edited by lo-n-slo; 04-28-2006 at 10:16 PM. Reason: Automerged Doublepost
#174
Originally Posted by lo-n-slo
That is awesome! I have been wanting to do that with my '94 c1500 for a while, But just dont have the experience to dive into the code side of it. What exactly did you have to do to the injector drivers? Have you driven it enough to notice a mpg increase? I bet it is a treat to drive!.....
Originally Posted by lo-n-slo
----------
Is that TBI you where running on the 305, a BBC unit, it looks like it in the pictures?
Is that TBI you where running on the 305, a BBC unit, it looks like it in the pictures?
#175
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Car: 1983 G20 Chevy
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Originally Posted by lo-n-slo
Is that TBI you where running on the 305, a BBC unit, it looks like it in the pictures?
This is a 454 TBI
This is a stock SBC TBI.
Another
#176
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Huh…
Huh….
Oh Crap… the gears are turning…
Now you got me thinking… my ’92 K1500 (it’s even the same color) has to come apart very soon, as in it has a blown head gasket or cracked head and I was planning on just swapping everything heads and up…
Huh…
The original plan was some vortec heads, adapt some intake, keep the TBI and convert to a ‘747 because the lack of info (and my relative stupidity with ecm stuff in general) for the ‘299 stuff is driving me crazy.
Oh man… what’s making this worse is that I have a whole new top end for my ’98 Formula 350, including new heads, cam, converted victor jr…, so I could potentially have pretty much all the hardware to do this except a spare throttle body but for the cost savings it would be very easy to get a nice aftermarket one for the formula and use the stocker… what I didn’t really have was a harness and was wondering if I could adapt the factory truck harness to work with one of the 730’s or 749’s that I have sitting around…
I really don’t need another project, tell me that this isn’t worth really considering… I have to say, as much as I basically hate the TPI setup, it does look really cool… That would give the truck a totally trick look under the hood. My gut is telling me that the TBI is still happier from idle to about 2500, which is 99% of the time that this truck is running.
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WHY? A normal peak and hold driver should run saturated injectors just fine… did you experience a problem or did you not even try it the stock injector driver?
Huh….
Oh Crap… the gears are turning…
Now you got me thinking… my ’92 K1500 (it’s even the same color) has to come apart very soon, as in it has a blown head gasket or cracked head and I was planning on just swapping everything heads and up…
Huh…
The original plan was some vortec heads, adapt some intake, keep the TBI and convert to a ‘747 because the lack of info (and my relative stupidity with ecm stuff in general) for the ‘299 stuff is driving me crazy.
Oh man… what’s making this worse is that I have a whole new top end for my ’98 Formula 350, including new heads, cam, converted victor jr…, so I could potentially have pretty much all the hardware to do this except a spare throttle body but for the cost savings it would be very easy to get a nice aftermarket one for the formula and use the stocker… what I didn’t really have was a harness and was wondering if I could adapt the factory truck harness to work with one of the 730’s or 749’s that I have sitting around…
I really don’t need another project, tell me that this isn’t worth really considering… I have to say, as much as I basically hate the TPI setup, it does look really cool… That would give the truck a totally trick look under the hood. My gut is telling me that the TBI is still happier from idle to about 2500, which is 99% of the time that this truck is running.
----------
Originally Posted by HaulnA$$
Without getting too technical, I basically just turned the injector drivers from "Peak & Hold" to just "Hold" drivers.
Last edited by 83 Crossfire TA; 04-29-2006 at 03:32 AM. Reason: Automerged Doublepost
#177
Originally Posted by 83 Crossfire TA
…….The original plan was some vortec heads, adapt some intake, keep the TBI and convert to a ‘747 because the lack of info (and my relative stupidity with ecm stuff in general) for the ‘299 stuff is driving me crazy......I really don’t need another project, tell me that this isn’t worth really considering… I have to say, as much as I basically hate the TPI setup, it does look really cool… That would give the truck a totally trick look under the hood. My gut is telling me that the TBI is still happier from idle to about 2500, which is 99% of the time that this truck is running.
Originally Posted by 83 Crossfire TA
----------
WHY? A normal peak and hold driver should run saturated injectors just fine… did you experience a problem or did you not even try it the stock injector driver?
WHY? A normal peak and hold driver should run saturated injectors just fine… did you experience a problem or did you not even try it the stock injector driver?
#178
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Originally Posted by HaulnA$$
First of all, this won't work on the '299. It will only work on the '93-'95 PCM's that control the electronic tranny's meaning the 16168625,16196395, and the 16197427 and maybe one or two others so whether it is worth it or not for you seems a lot less likely.
- I was planning on swapping PCM’s, just going in a different direction, it will cost me the same either way
- I need to pull everything off the engine down to the heads anyway because of the headgasket leak or cracked head
- I’ll have all the TPI hardware sitting around anyway, and using it would be cheaper then the originally planned swap
- The TPI looks cool
- It’s just a cool swap, ecm and hardware wise
The negatives:
- I don’t know that there is any real gain to be had with the TPI setup for the application (again, used as an actual truck, If I could have all the low end in the world below 2500 I would sacrifice over 3K in a second)
- Really, this thing is a truck used as a truck. The number one concern for it is that it be reliable and cheap to keep on the road, and past that as much low end for towing/hauling and as high an MPG as possible… I don’t know that this change would serve that
- “wasting” extra time tinkering with is is not high on my list of things to tinker with, I don’t have time to get done with my “real” f-body projects…
- I hate working on the TPI setup
It is the stock injedctor driver, just modified. A stock P&H driver is designed to drive one TBI injector or two low impedance port injectors with a peak current of around 4 amps. This is not a problem if you want to drive one, two, or possibly even three saturated injectors but four poses a problem. My injectors measured right at 14 Ohms each which means four in parallel measure 3.5 Ohms. At 13.8 Volts they would draw 3.94 Amps. This is right at the Peak to Hold threshold of the driver. Very bad. If the driver ever detects the peak current, it will switch to hold mode and lower the current to the injectors which, depending on the fuel pressure, is low enough to actually let some saturated injectors close before the injector pulse is over. In order to eliminate this possible problem, I modified the driver to never detect peak current. HTH
#179
Originally Posted by 83 Crossfire TA
.....So basically you left it as is but disabled the hold part, right? I haven’t looked at the circuit in those PCM’s but I would assume that each injector driver is actually 2 drivers one doing peak and the second doing hold, or is there more to this then that?
#180
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Car: 88 Camaro SC
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Axle/Gears: 9-bolt w/ 3.23's
Originally Posted by 83 Crossfire TA
I really don’t need another project, tell me that this isn’t worth really considering… I have to say, as much as I basically hate the TPI setup, it does look really cool… That would give the truck a totally trick look under the hood. My gut is telling me that the TBI is still happier from idle to about 2500, which is 99% of the time that this truck is running.
#181
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
BTW, that TPI does look cool. Nice work on the swap, HaulnA$$
On a side note, Ive gotten most of the code (sans transmission) done for the $0D. Im thinking of writing a patch to allow me to read in the freqency of the LS1 MAF that I have. The code is such that it would be a fairly straight forward conversion. Just need to figure out how to best divide the frequency a bit to keep the number of interrupts reasonable.
On a side note, Ive gotten most of the code (sans transmission) done for the $0D. Im thinking of writing a patch to allow me to read in the freqency of the LS1 MAF that I have. The code is such that it would be a fairly straight forward conversion. Just need to figure out how to best divide the frequency a bit to keep the number of interrupts reasonable.
#182
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Originally Posted by dimented24x7
Its would probably be worth doing. The PCM is perfect for this as it uses true speed density calcs and has lots of goodies in it, not to mention that it also supports the E-trans. Only downside is that its somewhat complicated compared to the earlier ECMs, but it also offers alot more functionality.
What’s worse is that I’m also really wondering about how this would work with my formula project (port injected with a 4L80e tranny), the big sticking point that I’m seeing is that it would need to play nice with a 2 bar (and probably eventually a 3 bar) map sensor.
Man, I wish that there was a book or something that I could sit down and study and figure out some of the real ECM hacking (well if you’re a computer guy it should be cracking, not hacking, but oh well…) so I could dive into this kind of project with some of you that have a real clue what is going on (for the life of me I can’t figure out how you’re figuring out what the lines of hex do in the first place), or at least if one of you were close enough that I could sponge info off of you till I was really up to speed (hell, even get a fraction as good as I am with things mechanical…)
#183
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
I have a partially completed hac that I can post later on. I posted it here before, but Ill post the most up to date one since its always changing. Most of the engine stuff is complete, but I havnt done anything with the transmission side of things as I wont be using a CC trans, or any form of automatic for that matter.
#185
Originally Posted by dimented24x7
BTW, that TPI does look cool. Nice work on the swap, HaulnA$$.....
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Car: 82 ElCamino, looking for a 3rd gen
Engine: 305 TPI(427SB in progress) 730 $8D
Transmission: THM350 (Getting a 4L80E soon)
Axle/Gears: 10 Bolt w/ 2.43 gears :(
Originally Posted by HaulnA$$
First of all, this won't work on the '299. It will only work on the '93-'95 PCM's that control the electronic tranny's meaning the 16168625,16196395, and the 16197427 and maybe one or two others so whether it is worth it or not for you seems a lot less likely.
It is the stock injedctor driver, just modified. A stock P&H driver is designed to drive one TBI injector or two low impedance port injectors with a peak current of around 4 amps. This is not a problem if you want to drive one, two, or possibly even three saturated injectors but four poses a problem. My injectors measured right at 14 Ohms each which means four in parallel measure 3.5 Ohms. At 13.8 Volts they would draw 3.94 Amps. This is right at the Peak to Hold threshold of the driver. Very bad. If the driver ever detects the peak current, it will switch to hold mode and lower the current to the injectors which, depending on the fuel pressure, is low enough to actually let some saturated injectors close before the injector pulse is over. In order to eliminate this possible problem, I modified the driver to never detect peak current. HTH
It is the stock injedctor driver, just modified. A stock P&H driver is designed to drive one TBI injector or two low impedance port injectors with a peak current of around 4 amps. This is not a problem if you want to drive one, two, or possibly even three saturated injectors but four poses a problem. My injectors measured right at 14 Ohms each which means four in parallel measure 3.5 Ohms. At 13.8 Volts they would draw 3.94 Amps. This is right at the Peak to Hold threshold of the driver. Very bad. If the driver ever detects the peak current, it will switch to hold mode and lower the current to the injectors which, depending on the fuel pressure, is low enough to actually let some saturated injectors close before the injector pulse is over. In order to eliminate this possible problem, I modified the driver to never detect peak current. HTH
Last edited by eric305TPI; 05-09-2006 at 11:36 AM.
#187
Originally Posted by eric305TPI
..... If you don't mind can you explain what needs to be changed on the actual PCB driver circuit to not allow the driver to enter the hold mode as well as the actual changes that need to be done to the netres set.
#188
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
I finally got a cheap-*** function generator to begin poking at the inputs. I finally confirmed that the transmission output speed is tied to actual honest to god pulse counters. They appear to run fine all the way up to around 40 kHz, or more, on a standard TTL signal.
This should mean that I can plug the frequency output from an LS1 MAF right into the TOS input, and read it directly without any complicated code. Mmmmm, airflow readings that are accurate to a few 10'ths of a percent. It also should be a simple plug and chug mod if its as easy as it appears to be. These PCMs definatly look like the next have to have item for the DIY'er.
This should mean that I can plug the frequency output from an LS1 MAF right into the TOS input, and read it directly without any complicated code. Mmmmm, airflow readings that are accurate to a few 10'ths of a percent. It also should be a simple plug and chug mod if its as easy as it appears to be. These PCMs definatly look like the next have to have item for the DIY'er.
#189
O-scope pics
I finally got my son out from behind the wheel long enough to hook up the O-Scope and record some pictures of the waveforms. Pardon the quality of the images, for some reason the floppy drive in the scope would'nt format my disk so I used the digital. The first pic is of the synchronous injector timing vs. DRP. The top waveform is DRP's from the IC signal on pin F11, the bottom is Inj. 1 from pin A16. As you can see, the injectors are firing every 4th DRP. The second waveform is both Inj. 1 and Inj. 2 together.
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Originally Posted by 89350STRO
pin out attached
It only takes this dumb ol country boy three tries to figure he was attaching a file in excess of 102500 bytes. (always read the directions last!!!)
The "Not Avail" pins must be made up in a transmission wiring harness, If you plan on using the 4L60E tranny.
The Mod B-7 is the modification Ben is talking about that must be done to the ESC module and replacement of the Knock Sensor or modify the circuit.
89350STRO
It only takes this dumb ol country boy three tries to figure he was attaching a file in excess of 102500 bytes. (always read the directions last!!!)
The "Not Avail" pins must be made up in a transmission wiring harness, If you plan on using the 4L60E tranny.
The Mod B-7 is the modification Ben is talking about that must be done to the ESC module and replacement of the Knock Sensor or modify the circuit.
89350STRO
#191
Originally Posted by dimented24x7
I just noticed this. With the PCM, from what I can tell, you have to use pin F13 for the VSS if no E-trans is present. Dont know if this was caught already or not. The others (pin F12/pin F??) are for the actual 40 pulse/rev output from the trans output shaft speed pickup pulses while pin F13 is for the output from the VSS buffer box. That output is used for the MPH term throughout the engine code. The only place pin F12 would be used otherwise is in the shift light code. Dont know why they did it that way rather then calculate it from the TOS revs but I cant say I can complain. It gives me another free input.
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
The only problem with the F13 input is that its sampled in the main fuel loop at 80 Hz if I recall. This means that after around 75 MPH, theres aliasing. IOW (for the rest of us non-EEs), itll start reading random speeds, and could even read near zero at certain conditions. Im not quite sure how that will effect a car when flying down the highway. That was sort of what caught me as odd, is that the input can be easily overrun. I guess they figured that GM owners are all law-abiding citizens that dont drive over 55.
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Originally Posted by HaulnA$$
As for free inputs, don't forget about pins F2 and F3 which are the Trans input speed VSS Hi and Lo which are only used on the 4L80E apps and $0E and $31 code.
#194
Originally Posted by dimented24x7
What sort of signal does that accept? Ive seen the pulse accumulator and counter reg. in the code as an alternate to the 5V signal thats supplied in the other apps.
Last edited by HaulnA$$; 10-11-2006 at 09:08 AM.
#195
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
thats cool. My TKO has a 12-tooth reluctor with a pickup. I would assume I could wire the pickups output to the high/low pins and use it to read in the vehicle speed?
#196
Originally Posted by dimented24x7
thats cool. My TKO has a 12-tooth reluctor with a pickup. I would assume I could wire the pickups output to the high/low pins and use it to read in the vehicle speed?
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Good to see this thread still alive!
I have now been running my 383 TBI with a '8625 for ome time and its fantastic!
I intend to switch to PFI mode soon, and once its working properly on the 383, I will swap it for the 406 I am building at the moment..
I have now been running my 383 TBI with a '8625 for ome time and its fantastic!
I intend to switch to PFI mode soon, and once its working properly on the 383, I will swap it for the 406 I am building at the moment..
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Originally Posted by HaulnA$$
Should work flawlessly, with the proper code, of course. That input was originally designed for the 4L80E code to directly measure tranny input shaft speed for slippage calcs vs. the output/VSS speed instead of relying on the RPM input which is obviously pre-converter. HTH
#199
Originally Posted by dimented24x7
I also recall seeing another VSS TOS input in the code as well. Have you seen any additional pin or pins for this listed?
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Are pins F2 AND F3 both for the pickup on the input shaft? Or is one for the pickup on the input shaft and one for the output shaft?