C207 connector under dash?

notime2d8

Daily Driver
Aug 22, 2008
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0
Birmingham, AL 35007
Hey, i'm swapping adding TBI injection to my 83 El Camino. I bought an uncut 4.3 tbi harness from a Monte Carlo. Under the dash where the ecm connects there's a white c207 connector, i found the pinout here:

Connector_1987_C207.gif




I have A,B,C,E,F,H and D,G,R,J are missing, can someone tell me if they have those if they are using a factory tbi harness, if they are needed, or where to get the missing connections from? Thanks
 

Doober

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Jun 2, 2003
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Catalina, AZ
www.cardomain.com
Having trouble picturing the connector, but I can't imagine a serious drawback... wiring will depend on what all you use, you could probably add the coolant fan wire for an ECM-controlled radiator fan, the emission/cold start I wouldn't be too concerned about (never seen anything extra for 'cold start' with TBI, only port style injection), pin G I'm not too sure about.

If you're planning on a performance TBI build, I recommend the EBL (dynamicefi.com), it's a flashable setup that uses the main board/case and only replaces part of the ECM. I'm running it with my 383 C1500 and I'm very happy. You can email Bob at DynamicEFI, and he may be able to help you out, he knows a ton about the GM efi stuff.

What are your plans for this setup? Engine info, etc.
 

notime2d8

Daily Driver
Thread starter
Aug 22, 2008
48
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0
Birmingham, AL 35007
Doober said:
Having trouble picturing the connector, but I can't imagine a serious drawback... wiring will depend on what all you use, you could probably add the coolant fan wire for an ECM-controlled radiator fan, the emission/cold start I wouldn't be too concerned about (never seen anything extra for 'cold start' with TBI, only port style injection), pin G I'm not too sure about.

If you're planning on a performance TBI build, I recommend the EBL (dynamicefi.com), it's a flashable setup that uses the main board/case and only replaces part of the ECM. I'm running it with my 383 C1500 and I'm very happy. You can email Bob at DynamicEFI, and he may be able to help you out, he knows a ton about the GM efi stuff.

What are your plans for this setup? Engine info, etc.


Hey thanks for the info. I have a 84 elco that was originally a diesel. I swapped in a new 290hp crate 350 and th350 trans. I’m going from a carb to TBI. I purchased an uncut TBI engine harness from a 87 monte carlo and where the harness connects to the computer there are two connectors that run to the fuse box, ALDL, VSS, etc… that’s what I needed the pinout on. I definitely want a EBL flash but that’s going to wait, I’m trying to stay under $1000 and have spent about $550 so far. After I get it running I plan on upgrading it to a new ported throttle body and adjustable regulator, after that then exhaust, EBL, transmission & posi rear end.

Just want a nice running street cruiser…nothing too fancy like your setup… :^o
 

Doober

Moderator
Jun 2, 2003
14,704
1
38
Catalina, AZ
www.cardomain.com
Bam! This is why I'm always raving about Bob and the EBL... awesome service, even with unrelated questions to the customer. Sounds like you're using the diagram from a Camaro?
I went through the wiring for a '87 4.3l Monte Carlo. In that car this is connector C434.

D & G This is ignition switched power. Make sure that it is ignition, not accessory power. Uses a 7.5A fuse and powers the injectors.

J ORG I couldn't find this terminal. Orange is usually battery power.

R This is from the 3A cranking fuse in the fuse block. It is hot whenever the starter is activated. Lets the ECM know this.

I wouldn't go by that Camaro diagram of C207 either. As terminal B for the '87 Monte is power back to the fuel pump and as an input to the ECM.

N is shown for the P/N switch input to the ECM.

Stock TBI will definitely be very short on fueling... it will have to be tuned for that 90hp difference (considering the stock tune is for a 200hp engine), because you will need more injector/pressure to feed it, and with a stock tune you're stuck at either too much fuel at idle, or not enough at WOT.

The EBL comes with a nice little utility that helps with calculating fueling, BPC (injector base pulse constant), and a few other things, and it looks like you can run 454 injectors (TBI injectors all interchange with each other) at stock fuel pressure to get the fuel you'll need... but it may run rich at idle, which is why it would need the tune.

For exhaust you may be able to run LT1 exhaust manifolds, I'm not sure about interference with the crossmember though. They're good enough for a 300hp production engine, just a thought :)
2a4zfk0.jpg
 

notime2d8

Daily Driver
Thread starter
Aug 22, 2008
48
0
0
Birmingham, AL 35007
Doober said:
Bam! This is why I'm always raving about Bob and the EBL... awesome service, even with unrelated questions to the customer. Sounds like you're using the diagram from a Camaro?
I went through the wiring for a '87 4.3l Monte Carlo. In that car this is connector C434.

D & G This is ignition switched power. Make sure that it is ignition, not accessory power. Uses a 7.5A fuse and powers the injectors.

J ORG I couldn't find this terminal. Orange is usually battery power.

R This is from the 3A cranking fuse in the fuse block. It is hot whenever the starter is activated. Lets the ECM know this.

I wouldn't go by that Camaro diagram of C207 either. As terminal B for the '87 Monte is power back to the fuel pump and as an input to the ECM.

N is shown for the P/N switch input to the ECM.

Stock TBI will definitely be very short on fueling... it will have to be tuned for that 90hp difference (considering the stock tune is for a 200hp engine), because you will need more injector/pressure to feed it, and with a stock tune you're stuck at either too much fuel at idle, or not enough at WOT.

The EBL comes with a nice little utility that helps with calculating fueling, BPC (injector base pulse constant), and a few other things, and it looks like you can run 454 injectors (TBI injectors all interchange with each other) at stock fuel pressure to get the fuel you'll need... but it may run rich at idle, which is why it would need the tune.

For exhaust you may be able to run LT1 exhaust manifolds, I'm not sure about interference with the crossmember though. They're good enough for a 300hp production engine, just a thought :)
2a4zfk0.jpg


dancin_banana.gif Man thanks so much!!! I was wondering why i only had power to one injector. But now i don't know where the power for the fuel pump comes from. Could you ask for all of the pins? With a promise to get a EBL in like 4 months?


Edit: Yes, I went home and wired up pin D and that gave me power to my other injector. I just need to figure out how the stock fuel pump is wired. Trying to avoid tapping into the wire coming from the fuel pump relay. I still have to finish putting in my pump. upgrading fuel lines, and intake....but i might be running this weekend... \:D/
 

notime2d8

Daily Driver
Thread starter
Aug 22, 2008
48
0
0
Birmingham, AL 35007
I'm still having issues ](*,) What i thought was two grounds have 10v going through them and that drops to 0.2 if i ground it. Winaldl shows my TPS sensor at -12.3, and my timing seems to be off by alot even though i think i set it right. help please.
 

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