Could someone show me a link where it shows exactly what I have to do as far as repinning my ecm connectors goes? I would like to convert from my 730 to a 749. Or is it just possible to flash my eprom with a syty bin and use my 730 to see boost? If so where can I get this info? I've looked around on the syty sites but can't seem to find to much info on this stuff. I'm getting ready to install a D1SC stage II and would like to use my ecm for tuning instead of the fmu in the supercharger kit.

 

I don't think there is a direct link to something like that but if you go to DIY EFI and look around on the FTP site you'll more than likely find a wiring diagram for what you need. Maybe even on the GMECM page under info about your particular ecm. If you can't find anything, I'll try and get you a wiring diagram from work but that won't be til Friday. I wish I could tell you that you could just run the syty code in the 730 but I don't know if it has ever been accomplished correctly. There is a thread on the GMECM list in the archives called "749 in a 730" or something that went on forever. I can't remember what the final outcome was though.

 

Well sort of.
You need to work out the details of cylinder slect, injector sizing, and in general read thru the calibration parameters and set thing up for a v8 and recal things as necessary.

 

It has been hashed out here as well. I posted some time ago the pinout differences between a 91 Camaro 7730 & the SyTy 7749. I think it was also 7730 in a 7749 or somthing like that. Search on that or Saturn5 or Bobalos & you will find it. <1 year ago.

BW

 

I would be very interested in reading that thread! I looked for it, but didnot find it? Do you need the $58Definition file for TC?

 

my question about the $58 definition file was in reguards to using the 749 in a 730. I would assume that you need the 749 definition file, right?

 

if you are going to run the SyTy code ($58 I believe) in the 7730 you are going to have to re-pin the harness so that the drivers are driving the proper outputs. if you want to do that, then Yes you are going to have to re-pin. also if you are going to do this you are going to have to obviously run the SyTy code.

If you are going to run a V8, expect a LOT of tuning. I guess (& No I have not done it, but it HAS been done), that there is a LOT of tuning to get it working well. I dont know why, but this is not simply a matter of changing it to an 8 Cly, the right displacement/Cyl, injector sizes & away you go. I dont know why, but it is apparently, quite a bit of tuning work, to get it to run well.

You are also going to have to have a V8 MemCal, regardless of what ECM you run if you are going to run a V8. That is to say, that if you decide to go the other way & just run your V8 with the SyTy ecm (7749) you are still going to have to have a V8 memcal in the car & make all the above changes & do quite a bit of tuning. the advantage of this is that there are a lot of cool tools that the SyTy crew have made for this configuration.

Here is the link to that post that I was talking about. https://www.thirdgen.org/techbb2/sho...threadid=92503

hth's
BW

 

One thing to note, Sunbird turbo = SyTy.

BW

 

Thanks for the response everyone. Ok I found the ecm connector diagrams for both computers at diy-efi. This should enable me to get a 749 in place of my 730. By the way I just called a local wrecking yard and they have a 749 out of a turbo sunbird and they said they would sell it for $50, so I'll pick it up on Friday. I downloaded a bin for a syclone from diy-efi named BBZA is this a good bin to start with? Also in the post you linked to Bobalos you and saturn refer to editing the prom. Which program did you use to edit it? I was just thinking of getting the $58 tunercat file would this work? I figured this would be a lot of work but worth it in the end. Mainly because I feel using the ecm to tune and not a fmu is the right way to do it, and the aftermarket ecm's wouldn't allow me to run my cruise control and other factory systems like a 749 would. Am I right in thinking I can port all of my 305tpi settings from 30 to 100Kpa right to the syclone bin and then tune the boost part of it? My car is a manual too so maybe this will help make things easier too? Also where can I find these tools you speak of for the syty code?
BTW Thanks for your time and patience(spelling?) everyone.

 

Hello Yenko, What I have used to program the PROM is a program called Promgrammer 98 or 01 (01 is later version, more features and 3 bar MAP option). For ALDL monitering I use Andy Whittaker's FreeScan. You will need to swap the injector ground and TCC as per Bobalos's prior post and use a 730 V8 memcal with $58 code on the Prom. The only changes I have made so far is to change the cylinder select to 8 and adjust the injector constant to match my injectors and enabled the manual logic. I am running in Naturally Asperated now and later will add boost. Can't give anymore insite as I am just getting the driveline finished, just finished the nine inch housing and still need to finish the brakes, shocks and driveshaft. But she runs, fires up easily, still a tad rich at idle but until I get some road time no further changes will be made to the Prom. cheers, Bob

Free scan is available here:
http://www.andywhittaker.com/ecu/

Promgrammer 01 is shareware available here:
http://home.swbell.net/loeryder/prom.html

 

Ok I finished my D1SC install last night and now I'll work on rewiring my car for the 749 ECM. A couple questions though, I have the ECM schematics for a turbo sunbird and some of the info on it disagrees with the info you posted Bobalos are they diff? Also is there anywhere on the net that has the schematics for the syty ecm config if it is diff? Saturn which bit did you change to get the vss to work as my 91 Z28 has the electric speedo and I would like it to work?

 

I compared a $8D camaro 7730 ECM diagram to the sunbird turbo 7749 ECM via the prints & that is where I came up with the list. They both use the same base ECM but they are populated a bit differently (injector drivers are different I think).

the SyTy's & Turbo Sunbirds used the same ECM & mask ($58) so the print that you use is not important. you can get a copy of a Sy print ftp://ftp.diy-efi.org/incoming/ I dont recall where I got the print that I used for my comparison.

I got the print for my 7730 from Ludis site (http://www.cruzers.com/~ludis/p4xref.html) & I think that you ought to be able to get the turbo sunbird one there as well.

one thing to note is that I found on the 7730 that one print that I looked @ said that an injector ground came out @ D1 (I just made that number up I think that you will see where I am going with this) & another print said that it came out @ D3, but when you look @ the actual print of the ECM you will see that they are connected to the same place internally to the ECM. I am willing to be that most of what you are seeing for differences is this (@ least I hope so). we do this all the time @ work it has to do with the amount of current that you can put through a small pin connector. if the load is going to exceed what the one pin can handle, we use more than one pin & then connect them back together @ some point in the harness.

if you are using GME Pro or Tuner cat there is actually a bit that you see for Magnetic or optical VSS, it is just on or off. I dont recall off of the top of my head what it is called, but it is pretty obvious. if you are editing it in Hex, I am sorry but I dont know the address.

hth's
BW

 

The Sunbird is set up to run 4 Peak and Hold TPI style injectors, while the Syclone is for running injectors in the saturated mode.

So you need to do the injector wiring as it is shown in the Syclone application.

 

Ok I have a couple questions for Saturn5 or anyone who knows. Which wires did you swap to get the injector drivers and injector ground? So far it looks like
730--->749
C11 ->C10 for injectors 1,3,5,7
C12 ->C11 for injectors 2,4,6,8
D6 --> D5 ground for 1,3,5,7
D7 --> D6 ground for 2,4,6,8

Does this look correct or is this wrong?
Also Bobalos you list the IAC drivers for the 730 and 749 as being differrent. Are they? Because my notes show that the IAC drivers are wired exactly the same for both ECMs. Thanks for everyones help.

 

The differance as grumpy said is between the two setups, sy/ty and sunbird. Sunbird is the same as 730. SY/TY is differant from the other two. I had a tough time finding the sy/ty schematics myself but I did find them. I'll send them to ya.

 

Just need to take the Ground for for the injectors from D6 (730) and move it to C13 (749). The others remain the same. The TCC is moved from F6 (730) to F4 (749). The IAC is reversed from 730 to 749 eg coil A (730) is coil B (749), I just swapped to match the 749 diagrams. I used the CAC Pump control E8 (749) to control my dual F-body fans. I have the correct SyTy wiring diagrams and can email them if you need them. cheers, Bob

 

Hey Bob,

how about uploading them onto the Incoming server @ the DIY site, so that they are there for future access?

thanks
BW

 

Okays, can do. See SyTyWiring.zip in incoming cheers, Bob

<EDIT> Duh! all four files are already on incoming see syclone ecm 1, 2,3, and syecmpin.pdf

 

Cool, thanks mucho any way.

Bob

 

Hey guys thanks for all the help. I repinned my harness as you explained saturn. I then burned a chip for the cyclone and told pocket programmer to start at 04000. Only problem is my car is now giving me a code 51. I take it that means bad or wrong memcal or ECM? So I reswapped the wires for the 730 and reburned the chip and it works just fine. The car would start and run but not very well as in it would barely idle and any throttle would kill the engine. Do you think the ECM I bought from the junkyard is bad? I emailed gmpartsdirect and they said they replaced ecm pn 1227749 with another part number. Do you think this new part number would work just fine or should I hunt around for another 749? Thanks again for all your help, without you guys I would have never found the wiring diagrams to repin my connectors.

 

Need more info here... First did you use the SyTy code $58? I'm using AYBN as a base. Second did you change the "knumcyl" in the bin to "0" (8 cyl). Next is did you change the injector constant to match yours. You will need to convert to gallons per hour instead of LPH. Also the $58 code is set for a 2 BAR MAP stock, did you swap to a 2 BAR MAP? The $58 will allow a 1 BAR MAP, just disable the 2BAR option. Yes the 749 has a superseded # number, check Lugis's site. With burning the chip at $4000 I'm guessing you are using a 27/29c256 Eprom. Good luck, HTH, Bob

 

Heres a copy of my current bin, just the cyl changed and the injectors set for 22lbs. Maybe this will help.

 

Hi Saturn yes I did program with the aybn code. I did everything you mentioned 8cyl, 1 bar map, 19 lb/hr injectors and all using tunercat $58. Yes I am using an amtel AT29C256 chip that is why I started at 04000. At first I didn't start at 04000 and the check engine light was on constantly with no codes. I then programed at 04000 and I would get code 12 and 51. I am using my 305 tpi V8 memcal too. Any insight?

 

I don't have an answer, other than does tunercat/you recalculate the checksum? Code 51 is a prom fail, Code 12 indicates no ref pulse. Its possible the 749 ECM maybe cooked, not sure. Bob

 

Ok I retried the 730 to 749 thing and this time it seems to be working well. This is how I repinned it.
730----->749
A8------->A9 Serial data for ALDL
C1------->B12 CC VSS input (from sunbird diagram)
D6------->C13 Injector ground
E6------->E3 IAC B low
E3------->E6 IAC A high
E4------->E5 IAC A low
E5------->E4 IAC B high
F1------->disconnected (shift light)
F2------->disconnected (port switch solenoid)

This time I started with the BBZB bin as the base and modded it to 8 cyl, 1 bar map, 19lbs/hr inj, etc. Now after looking through the code with programmer 01 I see that there is code for a shift light in the syty bin. Does anyone know which pin by chance would send the signal to the shift light? The car starts up and runs for a bit and then dies. This is no big deal since I have to start tuning the tables to get this 305 to run and my father is going to let me borrow his laptop and ALDL cable to get it tuned up. What exactly is the CAC pump? And where in programer 01 did you go to change the temp for it to control your fan Saturn?

 

Thats cool you got it running, Hehe the ALDL is the same (A8,A9) are connected inside the ECM. The CAC is the control for the intercooler pump on a SyTy (its a water to air intercooler), so far I haven't changed the setting as mine seems to kick the fan at 175* ish. The shift light is something I have not found yet as, the 730 uses F1 for it and the 749 controls the A/C relay with F1. I'm sure its there, I need to find a copy of a 5 speed 2.0L Sunbird turbo as all SyTy were autos. cheers, Bob

 

Yenko,

Anything new to report on your project? Have you tried to program boost? I am very interested in your level of success. I will be starting to tune a 455 olds with an 871 blower in a street rod. The owner installed a 730 ECM with a stock TPI 1 bar MAP. I told him there was probably no way to tune his rod with 8D code. Your conversion to the 749 may provide a solution. It still sounds like a long shot for tuning. I'm kinda thinking that the roots blower pulses is really going to give me fits! This is such a cool project, I'd hate to tell the guy he has to go buy a DFI or something. Any insight or progress on your project would be greatly appreciated.

Thanks
Steve

 

Hi Steve, yes I have hooked the 749 up and it would run. Right now I am swapped back to the 730 until my 2 bar map sensor and 30lb/hr injectors come in. Once I get them installed and the 749 hooked back up and have everything working I'll post my results. The only thing with the roots blower is don't they produce boost all the time? If they do I would think it would be easier to tune than a turbo or supercharger where you go from vacume to boost. But that is only speculation on my part.

 

I'll let the cat out of the bag and say shortly I'll have some info on a roots blower with a 749. Presently building the brackets to mount a Eaton M90 blower on my Bu. Still need to score 4 more injectors and get the correct pulley. But I should have it fired up in the next couple weeks. cheers, Bob

 

Bob,

What happened to the turbo's? i thought you were almost done with them?

Bob

 

Was just too much time , $$ and I just didn't like the way the it was turning out. Plus both T3's needed rebuilt, were a tad small A/R wise, plus I got enuf for both of em to pay for the Eaton. I still have the intercoolers, will use one presently, may add a second M90 and intercooler once I pay off some bills and build a decent 355/383. Sorta going Mikes route ala www.toohighpsi.com with TPI, might give the LT1 intake a try as well. Also nothin against turbos, they are more effective than a roots style since they by design don't have any parasitic losses, but hey its different. I am mounting the blower where the A/C delete pulley was and placing the blower over the valve cover. Will post some pics once the brackets are finished. cheers, Bob

 

just a shot of the blower mounting so far..

 

Looks good Saturn. Isn't that a screw style and not a roots though?

 

OMG, I'm glad you're doing the plumbing and not me! I thought that a screw blower was just another name for a roots style. Am I wrong.

BTW, Can anyone explain the difference between a peak and hold vs saturated injectors to an electronically challanged Mechanical Engineer?

Sounds like my blown 455 project is going to be a go. The guy that owns the truck says he'd like to try to get it to run without going to DFI. I'll get started after racing season is over. Let the games begin!

 

Eaton refers to their blowers as roots style. It is a tri lobe blower.
Peak and Hold are low impedence injectors
Saturated are high impedence injectors.

 

Right on Amigo. Good luck with it.

Bob

 

Yenko & Saturn,

Any more progress on your projects? I'd sure like to hear of your successes. I haven't started working on the Olds yet. Racing is over in November so I'll dig in then

Thanks

Steve

 

I have the blower mount done, tubing is done, have the belt on and the injectors in. I just need to finish the "hat" for the output to the intercooler and hook up my boost gauge. I have fired it up with it open, souns like a homing siren for mosquitoes. I have the next 4 days off so I think I'll have the hat done in a few days. cheers, Bob

 

The data logs from my brother's M-90 blown car show the blower pulses to be pretty extreme. It's pretty common to see .2psi in one frame and 9psi in the next. He basically loads the values into a spreadsheet that averages them to figure out what boost he's actually seeing.

There was talk to average the signal to the MAP mechanically buy putting a blead in the line, but since the tuning seems to be spot on for now that hasn't been messed with. The pulses don't seem to confuse the ECM (He's using a Haltech F9 though)

 

use a vacum resivor to smooth out the pulse. have you ever used a air compressor without a tank ??? air pulsates like mad. add some volume to the line however and the airflow smooths out. same idea with a vacum resivor.

 

Saturn, Are you gonna make your BIN work public once you have got a good running setup?

I'd hate to have a million people (myself included, in the future) re-inventing the wheel to get it to work.

 

Yeah, once I have the basics set I'll turn a copy loose with documentation. I have had it running N/A with very few changes. Will have to see now with the Eaton and 38 pounders. cheers, Bob

 

Hey Bob,

What I want to do this winter is:

Remove the MSD BTM
Remove the vortech FMU

And run 749 code (or 808, not sure yet).
I'm running 7-10psi of boost right now. I'll prolly upgrade my A-Trim for a T-trim or something
like that.

I don't think its easy to run w/out the BTM and FMU with the 165.. I'll either run rich at idle + lean under boost, or pig rich or lean at both.

-- Joe

 

Finally got the outlet pipe done, just need to pick up a LT1 1LE elow and redo the TB pipe. Got it to fire with the new injectors and Eaton, tho it took a bit. cheers, Bob

 

Just wanted to update everyone I finally installed the 749 ecm and have the car running. I've burned about 10 chips so far and it is running better with every chip. I have to say this is a great success and I know with some more tuning and a wbO2 setup I can get more power out of it than I was producing with the stock ecm and a FMU. Another great thing is cruise control, shift light, electronic speedo and everything work great unlike expensive aftermarket ecm's.

 

YenkoZ28, I'm assuming you're running a boosted application, any details? What injectors are you using?

 

Ok here are my specs:
91 Z28 305 tpi 5 speed manual w/ 3:08 posi.

This car is mostly stock motorwise except for the ATI procharger D1SC stage II(9psi pulley). The factory intake has been ported and polished and the AIR system has been removed along with the throttle body coolant setup. I have a few things like a MSD supercoil, accell 300+ wires and plugs one heat range colder than stock. I am also using accell 30lb/hr injectors(same size as a stock syclone injector). After about one month of installing the procharger I decided that I wanted computer control, so I installed the 749 ecm. I used the syclone BBZB code as a base and started from there software wise. For the hardware I installed a 2bar map sensor, MAT with the exposed thermistor(for accuracy), and repinned my factory connectors to work with the 749. It is great because now I can monitor my ecm with datamaster under boost conditions too. Another advantage is being able to modify the spark curve and fuel under boost conditions. If you are thinking of doing this I can tell you which wires to repin on the connectors and stuff.

 

yenko, i'm most definatly thinking of doing this this winter and any help you could provide would be greatly welcomed. my setup will be a lot like yours but with a paxton and a 350. im planning on repinning as stated above and going from there. if you have any more tips or are thinking of a tech article that would be great.
i'm sure ill have more questions once i start but thanks for the push in the right direction.
pete

 

Saturn and Yenko,

Any progress to report on your projects? I'm still considering trying to run Sy code in my 730 but I haven't really seen anyone on the board fess up and say they were successful at it. BTW I need GM part numbers for the ECM replacement for the749 and also GM part number for a 2 bar map sensor.

Any help is appreciated.

Good luck!

Steve

 

Shes ready to fire, just waiting on the injectors to arrive. Other than that, bolted the rear in last night and reassembled the doors/window cranks,glass tonight. Tomorrow going to wire in the solenoids (shaved handles/locks) and do some other small stuff. Need to bleed the brakes yet, and get the correct u-bolts for the rear yoke. But its getting close to getting some street time...