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

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.

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.

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.

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

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.

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.

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...

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.

Well, yes, i'm running a 1998, the dist cam has been set retarded atdc 20° to set the injector, it gave a fault P1345 (timing marks of crank and cam not set correctly), after checking all of the marks (all was ok) and setting the injectors, the dist was set as it is supposed to be, the fault and engine light was gone, and using timing light found out that now it's early 14.2°, that was the latest moves. But unfortunately computer does not control the spark timing, spark timing is only set by the distributer! 1996-1998 engines have mechanical ignition control, electronic ignition is only when you have no distributer and have ignition coil with bobbin for each spark plug. That is my main problem, I guess the only way I can try to some how get a more stable working engine is by playing with fuel/air mixture, and MAP sensor, but MAP sensor is just a sensor, that is just sending readings to compute, I think it can only be calibrated and may be not even. So how to get rid of BTDC 14.2° difference, I have no clue, and do I need to I don't know either. The engine works, it misfires to the exhaust, maybe if I correct the mixture it will not misfire and will work straight and stable, which I doubt. Will try to call programmer today, ask him to pass by with his computer. Will report the result.

did you use a 98 fuel punp? they have 60-65 psi when turning on the key.

If you are running a clear see through distributer cap, you don't need the scan tool. The stock CMP retard spec is Plus or Minus 2º.

I'm confused, are you running the blackbox PCM as well as the old TBI ECM at the same time? What did your tuner solder into, the TBI ECM or the blackbox PCM?

If you are running the 1996-99 Vortec blackbox, you cant adjust timing advance with the distributer, it must be adjusted in the calibration. You can only adjust the Camshaft Position Sensor (CMP) retard by loosening the distributer and clocking(twisting it) to get the + or - 2º spec.

https://www.youtube.com/watch?v=4G9_aCu2Bgw

https://www.youtube.com/watch?v=f9tjjxyEnbY

The only reason for the CMP retard adjustment is to prevent adjacent cylinders from crossfiring.

peace
Hog

That is an important part about the Vortec CSFI fuel pump, it will make over 90psi when dead-headed, and the CSFI regulator brings that down to 66 psi at atmospheric pressure. 66psi= approx. 4.5 BAR

peace
Hog

I think your last question is referencing the Roadrunner Emulator that the guys are using n the 512 -411 PCM. Craig Moates did make a Roadrunner work on a Blackbox PCM, but IIRC it was very very temperature sensitive.

The Roadrunner Emulator only allows you to make immediate changes to the calibration without reflashing, but you still need the Tunercats OBD2 or EFILIve software no matter what.

You could rip out your blackbox PCM and your 1990 TBI ECM and use an 0411 PCM to control your whole truck. Theres no reason why you cant use the blackbox to run the whole truck either, its just that fining places to recalibrate it are less common than the 0411 PCM. In other words, the Roadrunner would only save you time lost due to flashing the PCM's, as any changes you make via the TC2/EFILive are introduced into the calibration immediately. It doesn't prevent you from having to buy any tuning software. In fact in order to buy Tunercats OBD2, you must be a Roadrunner owner, or buy the 2 at the same time. I just checked at Moates and the Roadrunner emulator is currently unavailable.
http://www.moates.net/gm-1996present...-c-100_56.html

peace
Hog

Ok, so I guess I got you all confused a bit.
Let me try to make it clear.
I have a standard small block 5.7 EFI basically a TBI.
I installed Vortec heads with standard Vortec manifold and standard spider injectors. Throwing away my original ecu, and installed black box computer, with all the original Vortec wiring under the hood, inside cabin I left all original wiring, and joint the two together, the Vortec wiring under the hood and original in cab, it was a pain I the ass, to fined and join all necessary wires. Fuel pump I changed as well, for a more powerful one, don't remember the make, it is used for extra powerful tuned cars, so it has enough power, and standard Vortec CSFI regulator. So that is my setup.

I will make some pictures and post.