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General Tuning options w/o chipped ECU

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Thomas Mason

Proven Member
253
34
Apr 29, 2017
Covington, Kentucky
Hello, curious what tuning options are if you don’t have a modified ecu etc. not something I can budget currently to get custom stuff installed or purchase. How can I get a gsx tuned just to run correctly, nothing special
 
What are your goals the question is sort of vague. If you want a car that runs stock keep it that way, if you need a tuning device there are options out there. Have you done any research on it. Ecmlink it will help you monitor stuff, but again you're goals are.
 
I worded it wrong apparently. Currently my goal is just to have it running healthy... tune up and tuning is two different worlds I know, wrong choice of words. Just figure over time a car loses its strength and gets tampered with etc. stupid question I guess.
 
I worded it wrong apparently. Currently my goal is just to have it running healthy... tune up and tuning is two different worlds I know, wrong choice of words. Just figure over time a car loses its strength and gets tampered with etc. stupid question I guess.
You specifically mentioned chipped ecu. So are you talking about changing fueling and timing parameters or talking about replacing used parts? If you do not have different injectors than stock and you have the factory maf you need no chip or other "tuning " solution just to run and run correctly as stock. The only tune up stuff there is on these cars is basic automotive. Plugs, plug wires, filters. In extreme cases injectors need to be pulled and professionally cleaned.
 
If you have a 1g, a 2g MAF and 550 injectors cancel each other out beautifully within a percent of each other. I have also considered using the Evo 399 MAF and larger injectors, which would even work on a 2g, but lost interest in sorting that out.

Raising base fuel pressure will make your injectors "larger". I'm currently running a Evo III 16g into the upper 20s boost, with 650s and e85! The base fuel pressure is about double stock though.

Clocking the CAS is the hack of all hacks, there's lots of trade off, but up top in the RPMs you'll have your adjustment.

SAFCs, especially 5-knobs can be had for next to nothing these days and will allow you to get away with quite a bit.

The stock ECU targets a pigfat 9.6:1 AFratio, so even if you're just running pump gas, adding a gallon of e85 to every fill up would lean you out safely a tad and suppress knock quite well.

New spark plugs are awesome and cheap. Gap them tighter than stock.

There's other stuff, but I can't remember them right now.
 
That’s awesome . I have a 2G gsx 98 eclipse. Really thinking bout a evo 16g. Just gotta figure out the best supportive mods to go with. Thanks bro and merry Christmas
 
That’s awesome . I have a 2G gsx 98 eclipse. Really thinking bout a evo 16g. Just gotta figure out the best supportive mods to go with. Thanks bro and merry Christmas
Please take a look at the resources on this page. No need to search just stroll through the resource pages. Lots of information and yiu can catch up on decades worth of tried methods.
 
Yeah I have a lot of reading to catch up on. Sometimes I get Ansy looking for answers right away instead of reading cause I’m
Always on the move either working or wrenching
On the car ha ha
 
I have a 1g car that was running a GM maf and a GM maf translator that was "adjustable". It took a bit to get it tweaked but eventually ran pretty good with FP2 cams in it and what looked like a Ebay 16g on it.
It started a rod knock so I parked it right then since I have others to drive and work on. We rebuilt a stock motor to replace the engine and are putting that stuff in a 1990 GSX, soon to be profiled :cool:
 
Without needing to get into all the details, do the various "custom" ECU chips available for DSMs, especially the 1G, entail replacing just the CPU, or the entire ECU that's had its CPU swapped by some customizer outfit?

And once swapped, are the new settings hard-coded, or can they be adjusted by the user?

If the latter, I assume you need some special laptop, tablet or smartphone-based app and interface to change settings and view sensor readings, correct?

Finally, are there custom CPUs/ECUs that allow a proficient user to get into and modify the actual code, and if so what are we talking about in terms of programming language, programming environment (i.e. IDE), etc.

Obviously the latter can be quite dangerous if not done properly and carefully, potentially destroying the car and maybe even causing injury or property damage.

I'm merely curious as I have no intention of changing it any time soon, if ever, but good to know.

Btw does the stock ECU allow for any user adjustments, via app, or at least monitoring the various sensor outputs, OBD-style, and if so is it via the OBDI connector, or some other interface?

I actually have a programming background and have thought about building a simple Arduino-based OBDI reader that translates all those pulse-based codes to actual numbers, in real time, with basic recording abilities. Just haven't gotten around to it.
 
"Btw does the stock ECU allow for any user adjustments, via app, or at least monitoring the various sensor outputs, OBD-style, and if so is it via the OBDI connector, or some other interface?"

No, the eprom chip is burned and thats that. The reason for ecm link is it swaps out the eprom chip for a writable flash one and gives you a usb to odb2 translator cable and the software to access / change data
 
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Yeah I have a lot of reading to catch up on. Sometimes I get Ansy looking for answers right away instead of reading cause I’m
Always on the move either working or wrenching
On the car ha ha

You need an afr gauge.
My stock setup right now is running a 16g on 17psi at 10.5AFR under full load.
-This is on freshly cleaned fuel injectors and a brand new fuel pump, fuel filter and re-wire to fuel pump with 4gauge wire. Injen intake, full 3" turbo back exhaust.

I am going link because you cant tune for more fuel past 17ish psi on a 16g stock 450cc injectors

So far link was probably the cheapest part of the parts I have into this build, just havent installed it yet.
 
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"Btw does the stock ECU allow for any user adjustments, via app, or at least monitoring the various sensor outputs, OBD-style, and if so is it via the OBDI connector, or some other interface?"

No, the eprom chip is burned and thats that. The reason for ecm link is it swaps out the eprom chip for a writable flash one and gives you a usb to odb2 translator cable and the software to access / change data

Thanks. It's just a curiosity-type question for me now as I have no near term plans to mod.

I am though thinking of building a basic OBD1 reader for my 1G, using an Arduino, so I'd need a connector at the very least. I assume that it could work parasitically. They don't use much power. If it worked out and folks expressed interest I could post the schematics and code here.
 
Thanks. It's just a curiosity-type question for me now as I have no near term plans to mod.

I am though thinking of building a basic OBD1 reader for my 1G, using an Arduino, so I'd need a connector at the very least. I assume that it could work parasitically. They don't use much power. If it worked out and folks expressed interest I could post the schematics and code here.

Go for it! I dont know the specifics of what connections and data go to the odb1 ports. There are ODB2 readers that do what your looking for and quite well. The ELM327 is one of them. Maybe someone makes a ODB1 version somewhere?
 
I am though thinking of building a basic OBD1 reader for my 1G, using an Arduino, so I'd need a connector at the very least. I assume that it could work parasitically. They don't use much power. If it worked out and folks expressed interest I could post the schematics and code here.

There are several posts that might help you. First is how to build the interface to the 1G DLC (OBD1).

https://www.dsmtuners.com/threads/how-to-set-up-mmcd-make-a-logging-cable.203316/
https://www.dsmtuners.com/threads/the-easy-way-to-make-a-1g-usb-datalogging-cable.424006/

You'll want to look at the source code for MMCd and the datalogging part of the ECU code. With the Yahoo Groups DSM ECU Archive gone I'm not sure where either are easily found anymore. I know I wrote up a brief description on how it works but that was years ago and I'm not sure offhand which site it was on.

You can use TunerPro RT with the correct ADX file to log the ECU and compare the data with your code. And understanding the ADX file will help understand how the interface works and what the data means.

https://www.dsmtuners.com/threads/how-to-log-your-1g-with-tuner-pro-rt.429444/
 
Go for it! I dont know the specifics of what connections and data go to the odb1 ports. There are ODB2 readers that do what your looking for and quite well. The ELM327 is one of them. Maybe someone makes a ODB1 version somewhere?

There are OBD1 readers but they're rare and expensive, and given how simple the outputs are compared to OBD2, it's way cheaper to build your own (if you know enough electronics and programming, which I do). It's just a series of electric pulses of different lengths and numbers, each signifying this or that trouble code.

Reading them with an Arduino-style microcontroller (or the new Raspberry Pi Pico version) should be easy. The real "challenge" is how to output the results. On a small LED or LCD display on the reader, or just put it out on Bluetooth so you can read it on your phone? Or both?!? I can also set it to save as many readings as you like, with timestamps, onto a MicroSD card, so you can have it running continuously.

I know that people also connect laptops to their cars to view sensor readings, e.g. O2 level, crank position, etc. But is that just with 2G cars that have OBD2, or has it been done with 1G cars with just OBD1? I wonder how hard it would be to tap into the ECU connector and display those values as well, in real time, and record them. It would obviously have to be done in a way that didn't interfere with the ECU.

First the error code reader, though. A lot simpler.
 
There are several posts that might help you. First is how to build the interface to the 1G DLC (OBD1).

https://www.dsmtuners.com/threads/how-to-set-up-mmcd-make-a-logging-cable.203316/
https://www.dsmtuners.com/threads/the-easy-way-to-make-a-1g-usb-datalogging-cable.424006/

You'll want to look at the source code for MMCd and the datalogging part of the ECU code. With the Yahoo Groups DSM ECU Archive gone I'm not sure where either are easily found anymore. I know I wrote up a brief description on how it works but that was years ago and I'm not sure offhand which site it was on.

You can use TunerPro RT with the correct ADX file to log the ECU and compare the data with your code. And understanding the ADX file will help understand how the interface works and what the data means.

https://www.dsmtuners.com/threads/how-to-log-your-1g-with-tuner-pro-rt.429444/

I know nothing about Palm programming. I owned one way back when, and may even have researched how to program one, but if so I've forgotten it all. And since these things are very proprietary, I might as well start from scratch. As I wrote above the ODB1 output is very simple and probably only needs a few lines of code to read and save. The real challenge is designing a useful way to display and save them.

Also, I'd want a less clunky connector cable with the electronics on a circuit board. Do you know what kind of OBD connector the 1Gs use, e.g. DB9, DB25, etc.? Better to get that right than use alligator clips, especially if it's going to be connected full-time.
 
https://www.ebay.com/itm/12-Pin-ALD...863931?hash=item3fc689defb:g:7bUAAOSwnOtbFrE0

connects bluetooth

Our 'ALDL Bluetooth Code Reader/ Scanner / Adapter' allows for the monitoring and recording of GM vehicle performance data to the user's Android device. This adapter can be used with our own 'ALDL Scan' Android application. It is also compatible with 'ALDLDroid'. The adapter can also connect via Bluetooth to laptop computers for use with computer applications such as 'TTS Datamaster' and 'TunerPro RT'.
When used with our 'ALDL Scan' application, the user can also log four additional analog data channels via the rear DB9 connector. This allows for the connection of devices such as wide band oxygen sensors. Analog channels can be monitored and recorded right along with the ALDL data being read by the application.

Features:
- Switch selectable between 160 and 8192 baud
- Switch selectable 10K resistor across A and B pins (required on certain vehicles by some software programs)
- Logs four external analog signals when used with our 'ALDL Scan' Android App.
- LEDs to indicate power on and ALDL bus activity.
 
Thanks, but for now I'm just looking to make a basic CEL code reader. Later on, being able to read and save all incoming ECU sensor data in real time might be nice.

Do you know what kind of connector plugs into a 1G OBD1 port? I'd rather buy one that just plugs in and not have to jerry-rig one. Literally just the connector. I can handle the wiring myself.

Also, to read sensor (i.e. not just error code) data, I assume we're talking a whole other kind of connector, that goes between the harness ECU connector(s) and ECU, right? Any idea what kind of connector that is, for future reference?

If I'm asking about "trade secrets", my apologies. I don't know enough to know what I don't know! Like, I have no idea what MMCD, ALDL, etc., mean. I'm still trying to figure things out at the physical connection level.
 
OK never mind, looked it up. As best as I understand, ALDL is a proprietary HW/SW protocol developed by GM in the 80's to read diagnostic codes and sensor status prior to OBD being developed and standardized, that is apparently is what 1G DSMs use (so does this mean that OBD1 was based on ALDL?).

So I need an ALDL connector, specifically a 12 pin version for 1G DSMs, right? Any idea where to get one, cheap? Literally just the connector, or, at most, one with all the proper pins wired with female pin "receptacles" and wires.

Btw, I'm still confused on how to read sensor data, and not just error codes. This can all be done with a basic ALDL cable, with no need to connect anything between the ECU and harness connector? If so, it would use some sort of bidirectional signal to request sensor data from the ECU, right? I assumed that I'd have to capture and process each sensor's data in terms of pulse width, voltage, etc. No need for that?
 
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