k i just read the faq on the 8746 patch for the rev limiter that sounds great but i got a few questions. for one i dont understand how exactly to apply the patch but im gonna read a few more times first....but anyway where do i find this program from motorolla needed to apply these patches. also how is the rev limiter set up to start w/ and wont it still kick in first like i know on my auto it shifts about 4500 rpm and id like to make that 5500 rpm or a lil less to be safe to utilize the 081 heads i will be puttin on and the lt1 cam. also can u list other patches i may find for my 8746 ecm $61 and r these name specific like the .bins u sent me were or r they all the same? i did a search for 8746 patch and that demo was all i came up w/.

as i said i dont understand it at the moment on how to apply the patches or how your changin stuff by just the command lines but i assume that in the free motorolla program i read about so i want that first to see if i can grasp it (which will be one of the first things ive been able to grasp when it comes to prom tunning)

thanks
John

oh and one more thing i know i just asked if there r other patches but i also remember seeing a thread of people throwing around the idea of using a space from egr or smog code to do a adjustable fan turn on temp has this been done yet or is it possible?

 

Patches are bin specific. The authors will usually list what bins that they know the patch will work on. It may work on another bin. That would require research by the user.
There is usually a txt file with the patch with specific info.
The actual patch file will have a *.s19 name.
The S19_pat.exe is the file used to apply the patch to the bin. EXE stands for executable. In order to change large portions of the patch you will have to edit the *.asm file that may be included in the zip. Then you will have to compile the *.asm file again into an *.s19. For minor changes your are better off using a hex editor to change a value like the desired rev limit you want. You are best learning to use the hex editor first. Patch editing requires more understanding.
Do a search on Hex editor & Text editor on TGO. A few of us have listed what we use. For the patch stuff, see the patch demo method stickie and the source code for dummies stickie after you learn some more.
Most of these dos programs will list all of there commands if simply type there name in a dos prompt from the directory they are located in.

 

okay so what he was explaining was just how to edit the patches not ness. apply them i got ya...they should have a program to apply them if im understanding correctly then that was what im used to when patching a program (put it in that programs folder double click and apply patch). i will deff. search for that hex editor cuase id like to change that rpm to around 5500 as mentioned...i havent found any other patches listed for my ecm or .bin yet but i will keep searching. i think i can use what ever .bin i want in my 8746 ecm as long as its for that ecm and $61 mask, but i will probably go w/ the more recent ones. my original chip is a 89 bird chip but i do not have my car at the moment (getting a built rear diff. thrown on there) so i can not check and see.

and i just wanna appologize if i am beating these threads to death but i promise i have searched and i either just one thread or many many irrelevent ones. sorry i will try and reformate my searches but so far not to much luck.

 

Check the Patch Method Demo thread, there are two patches in it: the rev limiter and another that disables the force knock test (code43). The code43 patch is near the end of the thread.

The patch that JP mentioned that uses the IAT in a better way hasn't been posted. IIRC it only works on an auto trans engine as it uses some of the shift light table space. I'll have to dig it out and check it.

It is designed for engines that have cold air or an open element along with possibly a colder intake manifold. It uses the IAT in the full range to tweak the BPC. this allows it to compensate for the air intake temperature.

RBob.

 

didnt follow the last part but thats cool cause i do have an open element and the chip im gonna tune will be for the edelbrock tbi intake also...oh yeah and i do have a auto tranny so that would be wonderful if u do run across that patch for it...ill keep searching to see more on how the patches work cause i kinda get your demo thread but not 100% i think i will understand better if i find that editor or another hex editor to actually see the code in front of me instead of just tryin to get it w/ out ever seeing the .bin in hex form.

 

TP has a hex editor also.
I use it for changing things.
When I'm making a patch I use another one that has a search for Hex string feature.

 

what is TP and also what is the one u use that has a search feature id like to get both of em so that i can try and grasp this patch thing, if i dont ill atleast get a better idea after looking at the actual hex code rather than just the .bin editor like tuner pro

Thanks
John

 

ok i feel like my head is gonna explode....please explain some things to me

in the rpm patch i assume its not tranny specific like if this patch was made on a manual tranny bin will it change more than just those two things in an auto tranny bin?

ive been looking for a hex editor and still cant find one i think i will also need a dissasembler but i dunno like i said im so confused i dl a 16 bit dos dissasembler but cant get it to open even using the directions in the sticky.

and lets just say i wanted the use the rpm cut off at 5000 rpm would i just find the adress for rpm 5000/25. and to change this value in the patch do i need to dissasemble it or just open it in a hex editor (which i cant seem to find at the moment)

oh and if i set this as an rpm cutoff wont what ever made my tranny shift at 4500 rpm still kick in first??

and what site is it i find the patches at to dl w/ the descriptions of what it doest in the zip? Please someone help a newb out i really wanna learn this and it will be a very useful patch i belive. and once again sorry for any repeats but i have been searching i will take screen shots if need be to prove it but it just seems like im diggin in deeper and deeper and just getting more and more confused.

if any help i appreciate it thanks
John

 

Currently, as stock, the '8746 ECM (maskid $61) has a MPH limiter. This consists of two values, an upper cut off, and a lower enable. Once the MPH is greater then the upper MPH threshold the fuel from the injectors is stopped.

This is accomplished by the ECM programming the injector PW of 0. Injector doesn't open, no fuel, no power.

Once the MPH drops below the lower MPH threshold the ECM turns the fuel back on. At the MPH speed the limiter is typically set to the car just doesn't accelerate. Basically, it just won't go over the upper threshold.

Now, what the rev-limiter patch does is to change the code to instead of checking the MPH, it checks the engine RPM. Once the engine RPM exceeds the upper threshold the injector PW is set to 0. Once the RPM falls below the lower RPM limit the fuel is re-enabled.

So, the patch changes one byte of the bin to change the test from the MPH variable to the RPM variable.

Once this is done the upper and lower MPH calibration limits are now upper and lower RPM limits. That is all it does, nothing else. If the rev limit is set to 5,500 RPM and you miss shift the fuel gets cut preventing, or helping to prevent, engine damage. Something in the drivetrain breaks, lose traction on a slippery spot, whatever, and it will prevent the engine from over rev'ing .

Nice to have, and as one posted, 'sure beats a speed limiter.'

The Patch Demo Method thread was to show how patches can be released. Using an S19 file along with the s19_pat utility it makes it easy to release patches, along with making it easy for people to apply those patchs.

I also believe that JP's ECU/XDF for the '8746 includes the entries to set the upper and lower RPM thresholds.

RBob.

 

oh so it wont change my shift points at all then? is this done by the tranny or ecm i wonder if ecm id love to change that. i guess thats what the shift kit would do allow me to shift manually witch u can do w/ stock but it wont shift at the exact point u hit the next gear.

and rbob if u got time if u dont mind to look at my thread intitled rough tune u, jp, and grumpy r some that many look to for advice...as i said in there it may be unreasonable to some a request but i dont think so but im not everyone else so i dont know how they will view it (may think im being lazy but how u just broke that down made me understand and in many of the stickies its broke down to a certain point but not that extent.)

Thanks
John

 

can someone please tell me what this hack does and what it will work on it says in the text document that its from an 89 caprice 350 tbi auto but its the same as in the fbody...is this the one for the rev limiter? here it is

61.zip 61.zip File Size: 83.39 KB
Last Modified: Aug 9, 2004 at 8:29 am

and this is where i got it if someone can dl it and tell me what it does thanks

61.zip 61.zip File Size: 83.39 KB
Last Modified: Aug 9, 2004 at 8:29 am

sorry this is where i got it from
http://www.moates.net/fileman/index....%20and%20Hacks

 

The mask is $61.
The bcc is ANLU.

The mask is a template for all of the cal data in BIN.
ie SA tables, VE tables etc. Most or all $61 mask bins will have the same locations for the same items in the cal area.
The code area is bcc dependent. The code area for ANLU will have some things (functions) that other 61 masks may or may not have. And vice versa. You can use a hack to make an xdf for all of the things you want to modify while tuning. Also each 61 mask bin will have the same cal area locations. But the actual values in the cal area will be different to some degree. Once you get a good xdf. you can then use it to compare different BCC's with the same mask. So you can see what GM did going from a 305 to a 350 etc. Or Iron heads to AL heads etc.

For the most part, all 61 mask bins will have very similar code areas. But they will not be the same. That's why patches are bin specific. The commands listed in the code area will not always be in the same exact address on the chip.

To simplify, ANLU may have the VE lookup code start on line # 3000. While a different 61 mask bin may have it at 3024.
But the cal area will be layed out exaxtly the same. So to change the VE table in either bin you might change the value at line 855 in both bins.
Line numbers are only used for clarity. The actual values would be in hexidecimal.

For the hack to "work", you would have to assemble it or fix it so it would assemble, then convert it to a binary file.
Then compare it to an actual ANLU bin and verify it had no differences. Once you can do this. You can go back and add and delete code to the limits of your knowledge and the ecm's ability. Your a few years away.......

What most people use it for I guess is to learn how the code works. When I step on the gas, this and this and this happens. The pw will change because this value went up and this one went down etc. So if you want to know how the AE is calc'd. Learn how to read the code.
AE is hard. Spark and VE is considerably easier to follow.
IAC code is terrible too.

This bin will work on a 8746 or 7747 ecm. They are essentially the same.

It's a good thing I don't have to teach to put food on the table....

 

no i thought that was a great explanation of how the bcc works and how u have to be careful when appling a patch to make sure the points your changing r gonna be the correct ones. i assume i just look at the code and compare the address of the bin and make sure it makes w/ what ever value thats in the adress of the patch (like i dont want to be changing VE in my .bin when the patch was supposed to affect IAC just for an example) but i am starting to understand and now i have all the stock bins cause good ol Jon sent them to me so now i can choose where i wanna start.

Thanks for the good info
John