749 stock injector driver questions

[JoeLutz]

It is my understanding the the syty 749 has two injector drivers that each can handle two P+H injectors as in the case of the turbo sunbird.
Questions:

1. If I jump terminals D5 to D6 and C13 to C15 as in the sunbird wiring, will the syty software run both injector drivers?

2. When upgrading injector drivers for P+H injectors, are the injectors still all driven off one driver as in the with the stock saturated injectors?

3. If # 2 is no, are the injectors still driven of C11 and C12 or C10 and C11 like the sunbird?

Thanks,

Joe

 

[z28camaro]

1. The sy/ty software and turbo sunbird software is the same with just different tuning. Yes $58 will run both sat. or p&h injectors depending on how you wire it.

2. If you wire it up like the turbo sunbird(p&h) then it will use both drivers, and if you wire it up like a sy/ty(sat.) it will use one driver.

3. You must wire it just like the sunbird diagram to use both drivers, so C10 and C11 should be used. D5 and D6 should be jumpered, and C13 and C15 should be jumpered.

I just soldered better drivers in my ecm the other night and am currently running it with sat. injectors wired as a sy/ty. I am looking to buy some p&h injectors to try out in my car and see if it works. In my case I'll be using 8 p&h injectors, so things may get interestingly hot.

 

[leroy]

IIRC, according to the Syclone wiring schematics, one driver drives one bank, the other drives the other. I haven't actually traced the wires to make sure that is correct.

I don't have the sunbird wiring diagram.

FWIW, I've run peak and hold injectors for quite awhile with just injector driver upgrades, and a ecm1 fuse upgrade.

Jim

 

[JoeLutz]

I just soldered better drivers in my ecm the other night and am currently running it with sat. injectors wired as a sy/ty. I am looking to buy some p&h injectors to try out in my car and see if it works. In my case I'll be using 8 p&h injectors, so things may get interestingly hot.

Cool... Please excuse the pun. Let us know how it goes.

Jim, you can get the sunbird diagrams here.
http://www.diy-efi.org/gmecm/ecm_info/1227749/
under "Schematics/service info"

According to this thread, pins C11 and C12 are joined inside the ecm meaning all 6 syty injectors are firing together off of one driver.
http://www.diy-efi.org/gmecm/ecm_info/1227749/749.txt

Thanks gentlemen for the excellent info.

 

[E-Rue]

hmmmmmm........

e

 

[z28camaro]

Well I finally recieved the p&h injectors and put them in and the old car is running great. These injectors cured all of my idle stability problems with a little tuning. I need a new belt though I'm only hitting 5psi and it should be 8psi.