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Just go stand alone they said, it will be easy they said
Big learning curve figuring out what kind of connections go to various sensors as well as determining what has a dedicated input on the ECU and what utilizes a generic input. Like the throttle body has two TP sensors. Signal 1 goes to a dedicated pin on the ecu "Default primary Throttle Position sensor input" and signal 2 goes to a generic "0-5V analog signal input". The Accelerator pedal also has two sensors that both go to generic "0-5V analog signal input" as there is no default Accelerator pedal input.
One thing I'm still not sure of is regarding that both APP and TP sensors require separate 5V positive and 0-5V ground power. The AEM pinout information has 2 pins labeled as "Analog 0-5V sensor ground" as well as two "+5V Analog sensor power". These 4 pins split off to supply power to every 5V sensor. Though I'm not sure on this, as far as I can tell you can use any +5V with any 0-5V ground you want but then that raises the question why does both the accelerator pedal and the throttle body require two separate +5V and 0-5V grounds for each individual sensor? If my assumption above is correct I should be able to run both sensors off of the same two pins. Only thing I can figure out, it is either that way for robustness or I am wrong in my assumption. Some of the example diagrams provided, like the one for a BMW E3, shows the MAP sensor and the TPS both tied into a single 0-5V ground pin on the ECU but with each tapped into separate +5V and I can't figure out what the rhyme or reason is. If anyone has any insight on that I would appreciate your feedback. Ex BMW wire schematic LS example accelerator pedal and throttle body. LSJ TB is different in that it has 2 additional pins for an additional +5V power and ground. Pinout sensor ground Pinout sensor power
Big learning curve figuring out what kind of connections go to various sensors as well as determining what has a dedicated input on the ECU and what utilizes a generic input. Like the throttle body has two TP sensors. Signal 1 goes to a dedicated pin on the ecu "Default primary Throttle Position sensor input" and signal 2 goes to a generic "0-5V analog signal input". The Accelerator pedal also has two sensors that both go to generic "0-5V analog signal input" as there is no default Accelerator pedal input.
One thing I'm still not sure of is regarding that both APP and TP sensors require separate 5V positive and 0-5V ground power. The AEM pinout information has 2 pins labeled as "Analog 0-5V sensor ground" as well as two "+5V Analog sensor power". These 4 pins split off to supply power to every 5V sensor. Though I'm not sure on this, as far as I can tell you can use any +5V with any 0-5V ground you want but then that raises the question why does both the accelerator pedal and the throttle body require two separate +5V and 0-5V grounds for each individual sensor? If my assumption above is correct I should be able to run both sensors off of the same two pins. Only thing I can figure out, it is either that way for robustness or I am wrong in my assumption. Some of the example diagrams provided, like the one for a BMW E3, shows the MAP sensor and the TPS both tied into a single 0-5V ground pin on the ECU but with each tapped into separate +5V and I can't figure out what the rhyme or reason is. If anyone has any insight on that I would appreciate your feedback.
Gm did it as a fail safe for power reduced mode if one of the tp sensors or pedal position sensors failed. That way you still have "some" throttle control, it was kinda a stage 1 fail mode, if there was a failure of both sides then it would go into mode 2 and the throttle body defaulted to I think 30% open. Causing you to lose all throttle control.
Huge kudos for JD for attempting this with due diligence, and you Kolt for helping.
Kolt's been a huge help. Behind the scenes he also provided me with GM pinout diagrams for the Cobalt components which I would have had no other way of figuring out so can't say enough how much I appreciated that.
Definitely making really good progress so far. I would love setting up a standalone system but the tuning would be a issue for me.
I don't know how to tune either. We'll cross that bridge when we get there but I am hoping Trevor will help me get started at the very least and if he has time may figure out a way to have him help me dial it in. He's been helping as well answering some questions for me here and there.
If you put the 5v analog grounds on the chassis, there could be a ground offset and/or noise between the chassis and the ECM. If the 5V and it's low reference ("ground") are indeed electrically isolated, you would for sure have major problems if you don't use the dedicated 5v low reference. I would think the analog grounds would be connected internally though, maybe they have the pins available and preferred to avoid splicing the analog grounds together.
If you put the 5v analog grounds on the chassis, there could be a ground offset and/or noise between the chassis and the ECM. If the 5V and it's low reference ("ground") are indeed electrically isolated, you would for sure have major problems if you don't use the dedicated 5v low reference. I would think the analog grounds would be connected internally though, maybe they have the pins available and preferred to avoid splicing the analog grounds together.
I'm definitely not going to run a +5V with a regular ground. There are plenty of warnings in the regular pin out section to not do that. What I was in question about was if I could run either +5V to either 5V ground as there are two pins for each. It appears that I can and they do not need to be paired up.
- Changing carb jetting is synonymous with changing the injector open time (pulse width)
- Twisting the distributor and playing with weights is synonymous with typing in the actual degrees of advance in a load vs. rpm table
The fundamental challenge is learning a new language that is incrementally more complex than the language of carburetors. Going stand alone adds another incremental layer of complexity because of the old saying, "Garbage In, Garbage Out", you need to get the inputs and outputs right before getting into adjusting numbers in table.
I understand what all the parameters stand for and understand the tables. Its the hundreds of actual fine adjustments that I'm not proficient on. Carb and distributor tuning is easy and very linear, looking at tuning tables isn't
I understand what all the parameters stand for and understand the tables. Its the hundreds of actual fine adjustments that I'm not proficient on. Carb and distributor tuning is easy and very linear, looking at tuning tables isn't
"Linear", on the outside. If you watch the AFR on a carb vehicle you'll see it is not linear at all. With EFI, your AFR does whatever you tell it to, under WOT if you want 11.9:1, you get 11.9:1 across the RPM range.
Here is a VE table showing AFR errors in actual percentages. In HPT, you could copy the whole matrix, then in the matching calibration table you right-click and 'multiply by percentage' [divided by 2 when you get close]. If you go mass air flow, it is literally 1 row of numbers to adjust. MAF measure air flow, VE makes educated guesses of air flow
Image taken from here: http://www.vegasvettes.com/TechTips/...FI%20Class.pdf
Once you understand what controls what it gets much simpler but the problem comes when they change the software style on you like going from gen 4 to gen 5 controllers. All the new stuff is basically greek to me. Gen3/4 stuff is easy though. Standalone controllers simplify/unify everything so its much easier to understand than the factory controller which is really only meant to be used for emissions control.
Once you understand what controls what it gets much simpler but the problem comes when they change the software style on you like going from gen 4 to gen 5 controllers. All the new stuff is basically greek to me. Gen3/4 stuff is easy though. Standalone controllers simplify/unify everything so its much easier to understand than the factory controller which is really only meant to be used for emissions control.
To your point: I am running the E67, it has been maxed out when it was on it's old setup. I tricked it to work with 80 lb injectors, I have yet to figure out how to trick it to expand the range of the timing table, right now timing for 25 psi boost is good, but those numbers suck horrible for boost levels below it where it's not knock limited. Then things like no lift shift don't work, have to use an external boost controller, very limited engine protection, can't switch timing tables on the fly, no ability to drive a secondary throttle body (twincharger stuff), etc.
Haltech confirmed they can do Ecotec VVT with the elite 1500, was looking at Link but they never got back to me on the Ecotec VVT control. Just need to come up with that $1700
To your point: I am running the E67, it has been maxed out when it was on it's old setup. I tricked it to work with 80 lb injectors, I have yet to figure out how to trick it to expand the range of the timing table, right now timing for 25 psi boost is good, but those numbers suck horrible for boost levels below it where it's not knock limited. Then things like no lift shift don't work, have to use an external boost controller, very limited engine protection, can't switch timing tables on the fly, no ability to drive a secondary throttle body (twincharger stuff), etc.
Haltech confirmed they can do Ecotec VVT with the elite 1500, was looking at Link but they never got back to me on the Ecotec VVT control. Just need to come up with that $1700
You have to scale the airflow. Thats the only real way to get yourself back onto the timing table. How Ive seen it done is just max out the injector flow table at 63.5lb/hr and tune the maf like you normally would. You end up with much lower airflow reporting and keeps you well within the limits of the timing table. This obviously only will work on manual cars because it significantly throws off the the engine torque model, but my buddies car runs really well this way(wasnt tuned by me). The shitty thing is that 09+ gen4 controllers have 128lb/hr injector limit.
I always thought it would be cool to put a beefed up ldk with a big turbo in an old car like a Vega and do the standalone setup to make it work. Would make a killer rwd drag car.
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