SpeedPRO Installation Questions

dhegge

New Member
Hello I am new to this list and the SpeedPRO World. I have recently purchased a SpeedPRO B2B system w/WB02 from Harry/PTE. He also set me up with a special interface cable from Fasttrackperformance for my 93 vette to allow the SpeedPRO ECM and GM ECM to coexhist in harmony. I was told that this would be the best way to go, since this is a street car and driveability is still important. Lockup TC, Air, Cruise, Etc.

I have reviewed all of the documentation and have come up with a couple of questions. See Below:

1. When connecting the WB02, do I need to install another bung in the pipe and add it to the existing 2 o2 sensors that are already there for the GM ECM or can I just use one of the existing spots to thread the new WB02 sensor into? If I remove a factory o2 sensor due I need to connect both GM ECM leads to the still operational 02 sensor to fool the GM computer?

2. The car is Supercharged (5-8 PSI) of boost so I went with a 2-BAR Map sensor. I am assuming that since the stock ECM still expects a 1 BAR map sensor that I will need to use both and wire them accordingly rather than just replacing the stock 1-BAR MAP sensor is this correct?

3. According to the Docs that came with the SpeedPro ECM. The injector harness is customizable and should be as follows:

Type (Firing Ord) A B C D E F G H

GMV8 (18436572) Blk Brn Ylw Grn Org Blu Gry Ppl (Default)
LT1 (18436572) Ppl Gry Grn Yel Blk Org Brn Blu

If the firing orders are the same why is the LT1 pinned out special?

The SpeedPRO documentation says that this harness configuration is configured to operate the injectors in a configuration that minimizes fuel pressure loss.

So my question is what order does the SpeedPro Bank/Bank system fire the injectors? I realize they fire in pairs, but which pairs? AB, AD, etc.

Rear

G H
E F
C D
B A

Front

Thanks In Advance,
Doug
 
Doug,

Since the stock ECM will no longer have any impact on how the car runs, I don't know that it will be important to have both of the original O2 sensors in and working. There WILL be a check engine light on no matter what you do here. Unless you are aware of a reason that the ECM still needs both O2 sensors, I would say save yourself the work of adding another bung in the exhaust and use one for the Speed Pro O2 sensor.

I am not certain, but the MAP sensor may have an impact on how the transmission is controlled by the stock ECM. I'd be interested to hear input from others on this one... anyone??? :D I'm thinking that the computer uses the MAP sensor to determine engine load and adjust shift points accordingly. Of course with a one bar sensor, it will never see boost...

The injector harness should be pinned as according to the diagram to keep the injector harness away from the Optispark and the coil and wires. It's just a safeguard to prevent problems caused by electrical noise. Pinning the harness as specified in the instructions will make the 10 pin connector on the harness come in from the back of the motor instead of the front.

Four injectors fire at once with a bank to bank system. ABCD fire, then 180 degress later EFGH fire, and so on. Each cylinder gets two injector events per combustion cycle like a batch fire system works, but this way, only two injectors per rail are ever open at any given time IF it is wired correctly. 1843 are open, then 6572 are open. With only two injectors per rail open instead of four, the impact that the opening of the injectors has on fuel pressure in the rail is minimized.

Hope this helps.

Craig
 
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