I've read and reread all the info on this site and fsc and i'm still confused. Do I need something else to tune my truck? I kinda understand how it works in theroy, but when I try to apply stuff it dosent seem to work. I think what confuses me the most is the bin files. Someone please try and work with me just so I can kinda get the hang of this. Thanks guys

I am waaaay far from a tuning expert but I know microcomputer stuff down dead.

GM ECM's are simply little tiny computers, in the most basic sense. No disks or display etc. There's ONE program inside it. Car turns on -- that program runs. Turn it off, off it goes.

That program is stored in a PROM (Programmable Read-Only Memory). The PROM contains a fixed number of "slots" (eg. a 1227747 has a 4096 byte (slot) PROM). In each byte/slot is one instruction in the computer's program, or one byte of tuning data. Data and program are all mixed together, for GM's manufacturing convenience.

Each ECM has a program in it's PROM peculiar to each application (car, truck model, etc). The PROM is a container -- and what it contains is a "bin", short for "binary", short for "binary program image" etc.

A bin is very analogous to a xerox copy of a sheet of paper. A bin is the "story" on the paper -- not the paper itself. The paper is like the PROM. Paper or PROM container, and story or program the contents.

Each bin is particular to some model/engine/trans/etc combination. If you change stuff, you gotta change the tuning data that's stored in the PROM. Remember that the bin is just a copy of the PROM *contents*.

A bin editor is basically like a desktop word processor (that only lets you change certain parts of the bin). It

* reads the bin into it's own MODIFYABLE desktop/laptop memory
* lets you FIDDLE THE CONTENTS (make changes)
* save the now-modified bin, nd/or
* "burn" the changed bin into a PROM.

It would be analogous to getting a xerox copy of a paper story, typing it in exactly, changing a few words, and printing out a copy of the modified story.

Hope that helps.


Some of the other tuner stuff --

editing/burning PROMs is a pain in the a$$ -- so you can get "PROM emulator" gear that plugs into the ECM PROM socket (fooling the ECM into thinking there's a PROM there) but the "PROM contents" can be changed from a laptop. Very handy. Costs more, but is a hell of a lot easier to tune with!

Here's my try. In order to tune, you need a bin file, definition file, and an editor (I use Tuner Pro). The bin file is what you edit and burn to the chip. The definition file has to be the correct one for that particular bin file. This definition file allows you to edit the correct parts of the bin in the editor program. If you use the incorrect definition file with a bin, all your data will be messed up and incorrect in the editor program.

So take my car for example. 1988 IROC-Z. 1227165 ECM. The stock Bin file is ABYA.bin. The correct definition file for this bin is called "32B.xdf". So I downloaded ABYA.bin, and 32B.xdf. http://www.tunerpro.net/downloadBinDefs.htm

Then I open up Tuner Pro, and add the bin file I downloaded:


Then add the correct definition (xdf) file:


Now you can edit anything you want in the columns on the left:



I'm fairly new to this. So hopefully what I typed will be easier to understand for a beginner.

bins and definition files available on craigmoates website under downloads. best to use a "stock" .bin

ok so if i dont have an emulator, can i tune my truck? i can see all the info on my truck but when i change the flags is it actually doing anything or am i just pretending. These are some of the basic questions I have. thanks again

Without an emulator you will have to do these steps for every change:

to tune fuel maps:

* gather data through the ALDL connector, using WinALDL or something.
* Back home, run TunerPro RT or something.
* Load your bin
* edit it to make changes
* save the "new" bin with a new filename (yourbin.date.bin or something)
* "burn" a new PROM
* stick the prom into the ECM
* repeat as necessary.

To set flags, it's the same process only without the data gathering (sometimes, depends on what you are changing).

The emulator "emulates" the PROM, so you can make changes on the fly. It's obviously very handy for stuff like flags, idle speed, etc, you can do those with the car running and the laptop on the passenger seat. But for fuel maps, where you might change 1, 20, 100 values, lurching over the passenger seat to type sucks, and it's just asking for trouble (typos, not paying attention, etc). You're better off doing it as a batch like the PROM method; gather data, take it home, make changes to your bin, save, then load it into the emulator.

"load it into the emulator" takes the place of PROM burning.