747 $42 Code help
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From: Lehigh Valley, PA
Car: 1986 Pontiac Firebird S/E
Engine: LG4 TPI Conversion
Transmission: 700r4
Axle/Gears: 3.42 SLP Posi 10 Bolt
747 $42 Code help
I'm installing a TB setup on my car using the $42 code and a 747 ECM. My editing software is TunerPro.
I can't seem to find where I'm supposed to change the stock chip's CID and Injector size... either by search function here or within the software.
I'm running a low-end 350 with a holley TB, bored to match stock intake, small tube headers and 3" exhaust. Obviously, since the ecm is from a 305 truck you can imagine the car runs pretty poorly right now.
Thanks in advance!
I can't seem to find where I'm supposed to change the stock chip's CID and Injector size... either by search function here or within the software.
I'm running a low-end 350 with a holley TB, bored to match stock intake, small tube headers and 3" exhaust. Obviously, since the ecm is from a 305 truck you can imagine the car runs pretty poorly right now.
Thanks in advance!
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
There is a BPC (base pulse constant) term to set. It is a combination of injector flow and engine displacement. It is for EGR off. When the EGR is on there is a table of BPC values.
The EGR off BPC is at $D2B4
The EGR on BPC table is at $D324
The calculation is:
BPC = 1461.5 * (VOL/RATE)
VOL = Vol of 1 Cylinder in liters
RATE = Injector flow in gms/sec
RBob.
The EGR off BPC is at $D2B4
The EGR on BPC table is at $D324
The calculation is:
BPC = 1461.5 * (VOL/RATE)
VOL = Vol of 1 Cylinder in liters
RATE = Injector flow in gms/sec
RBob.
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