1990 Chevy silverado Z71 5.7 TBI EFI, vortec heads with CSFI conversion. NEED HELP!

[Aksl]

Hi everyone, i have a Chevy 5.7 pickup, i decided to make a vortec conversion, with vortec mainfold and CSFI,as well as PCM/ECU black box. Decided to leave my trnsmission 4L60, and all the dashboard in it`s original state with all the in cabin wiring.

So i fully restored the engine, sandblasted and painted. Installed KB flat top pistons, comp cam 08-467-8, and all the vortec top, mainfold and spider injector.

After puting it all together, setting up all timing marks: Crank, TDC, Distributer (my distributer does not have hall sensor, only cam position sensor), and starting the engine up, i get misfires in the exhast, and by cheking with timimg light on crank, i misout 13°-15° earlier.
So my question is, how to solve this issue, is it possible by adjusting through PCM/ECU Black Box the map sensor, to get a reasonable ignition spark timing? (or what else can i do to solve that)?

Second issue, i havent pluged in the gear box, for the PCM/ECU to recognize it, i wonder wht are the wire colors in dashboard, and to what plugs ant pins i should cconnect them to in my black box pin out?

At the last, i have taken my PMC/ECU to programmer, he has unsoldered the chip and soldered an addapter for the chip, so it can be taken off easialy, reprogrammed it. If i want to play with it myself, what softwear and pc link connector do you recomend me to use to programm it. Can i make a setup, like you guys do with the 411 PCM, where a usb cable is comming out of the PCM for direct programming?

Thank you all in advance for help!

Sincerely.

[Kitch]

So are you saying that your timing is looking like 13°-15° ATDC or BTDC?
Did you set your base timing, with the "base timing connector" unplugged?
TBI base timing is normally set at 0° degrees but the guys that have done the Vortec conversions in the past say the motors need maybe 10° BTDC to get them to idle better.

[Aksl]

Hello Kitch,
- It seems that my timing is BTDC.
- I`m not sure if while setting my base timing if i unpllugged the conector, don`t remember now..(
- well, probably true, couse i get 13°-15° BTDC, and engine works fine while cold, but when it heats, it starts to hardly hold the low rpm and while accelerating, it missfires in the exhast..
I have a clear distributer cap as well, so it is easy to see the spark, that gets preaty long.

[ony]

need a scan tool and set cam retard to 0 + or = 1.

[Kitch]

I'm still just learning about my older OBD-I PCM, yours is the newer OBD-II style that I don't know much about.
Being able to create log files that you can view the output from in a meaningful manner will help you see whats going on.
It might be that your engine is running okay in open loop when it's cold but once it warms up and goes into closed loop something is changing.

[Aksl]

Thank you guys for help and advice, I will try to get a scan tool tomorrow or day after tomorrow and test! If I get some log files outloaded, will post them here.

[Aksl]

I can hardly imagine, how I can get 0+-1 set with my set up, if only it is possible to do with ecu/pcm...

[ony]

if you are running a 1996 - 1999 you set the dist cam retard to set the injector timming,i think the computer controls all the spark timming.