Big Blue's Transformation

[85lebaront2]

Bill - Thanks for the notes on the pic. And I think you are telling me something I'd not realized. I think you are saying that the engine's 42-way connector doesn't have to be on the PDB but can go to the firewall. I'd assumed that there were many things in the engine harness that comes from the PDB, but now that I think about it that's not true. Essentially everything in the engine harness comes from the ECU.

Is that what you are trying to get me to realize? That it is something like this simple drawing?

Yes sir, I am. That is why I was advocating a disconnect there. The main point being that the existing 42 way on the engine harness will reach to the firewall. Options being (a) roughly an 18" run from firewall to the point where the engine harness branches off to the fender (b) run all the 35 or so circuits from the EEC, across to the fender, then forward to the PDC plug (which will be facing the wrong way) probably 5 - 6' feet of extending the wires. Does it make sense now? (can you hear me now? ).

You can either make a bracket to hold the already present 42 way body side plug and run all the needed wires through the oval hole and reseal or cut it open a little, make a mount plate and choose your color, black, gray or tan and I will send the appropriate 40 way connector to you.

[Gary Lewis]

Bill - Thanks for the notes on the pic. And I think you are telling me something I'd not realized. I think you are saying that the engine's 42-way connector doesn't have to be on the PDB but can go to the firewall. I'd assumed that there were many things in the engine harness that comes from the PDB, but now that I think about it that's not true. Essentially everything in the engine harness comes from the ECU.

Is that what you are trying to get me to realize? That it is something like this simple drawing?

Yes sir, I am. That is why I was advocating a disconnect there. The main point being that the existing 42 way on the engine harness will reach to the firewall. Options being (a) roughly an 18" run from firewall to the point where the engine harness branches off to the fender (b) run all the 35 or so circuits from the EEC, across to the fender, then forward to the PDC plug (which will be facing the wrong way) probably 5 - 6' feet of extending the wires. Does it make sense now? (can you hear me now? ).

You can either make a bracket to hold the already present 42 way body side plug and run all the needed wires through the oval hole and reseal or cut it open a little, make a mount plate and choose your color, black, gray or tan and I will send the appropriate 40 way connector to you.

Now I understand!

So, there may be enough wiring in the engine harness to reach the ECU if I put the connector at the firewall.

So for those circuits I won't need extra wire. And while I will need to extend the power and fuel pump relay wiring, there isn't much of that.

Easier!

Now I need to figure out what connectors to use. Thanks for your offer. I may take you up on it as I get closer to the time. But I have more checking to do.

Seems like one approach would be to disconnect the engine harness at the 42-way connector and see how it might fit on the firewall. Is that connector weatherproof?

[85lebaront2]

Now I understand!

So, there may be enough wiring in the engine harness to reach the ECU if I put the connector at the firewall.

So for those circuits I won't need extra wire. And while I will need to extend the power and fuel pump relay wiring, there isn't much of that.

Easier!

Now I need to figure out what connectors to use. Thanks for your offer. I may take you up on it as I get closer to the time. But I have more checking to do.

Seems like one approach would be to disconnect the engine harness at the 42-way connector and see how it might fit on the firewall. Is that connector weatherproof?

Short answer, no not completely. It is fine as an underhood connector but could let water leak if installed through a panel. That is why I said mounted on a bracket like the 302 Explorers or the mid 90s E-series. I also have some nice 40 and 50 way ones that are very weatherproof if sealed to the harness outer casing and I may still have a right angle boot but do have several dual inlet boots that straddle the bolt holding the underhood plug to the firewall. Big issue is the terminals are not at present available aftermarket whereas the Ford ones are.

 

[Gary Lewis]

Now I understand!

So, there may be enough wiring in the engine harness to reach the ECU if I put the connector at the firewall.

So for those circuits I won't need extra wire. And while I will need to extend the power and fuel pump relay wiring, there isn't much of that.

Easier!

Now I need to figure out what connectors to use. Thanks for your offer. I may take you up on it as I get closer to the time. But I have more checking to do.

Seems like one approach would be to disconnect the engine harness at the 42-way connector and see how it might fit on the firewall. Is that connector weatherproof?

Short answer, no not completely. It is fine as an underhood connector but could let water leak if installed through a panel. That is why I said mounted on a bracket like the 302 Explorers or the mid 90s E-series. I also have some nice 40 and 50 way ones that are very weatherproof if sealed to the harness outer casing and I may still have a right angle boot but do have several dual inlet boots that straddle the bolt holding the underhood plug to the firewall. Big issue is the terminals are not at present available aftermarket whereas the Ford ones are.

Scott has just come up with the proper grommet. So, why not do as you suggested and make a bracket to put the 42-way engine connector either on the firewall or the back of the engine and run everything through the grommet to the ECU mounted on a bracket in the '85/86 location?

It would be pretty easy to measure everything and then set up a jig on the work table to get the wiring to length and soldered/heat shrunk. I think the connector will go through the hole in the firewall, although I'll have to check to make sure, but if it will the whole thing could be done on the bench and then installed on the truck. I think I'll want some kind of connector to let me disconnect from the PDB so installation will be easier, but that shouldn't be too hard.

Something like this:

[85lebaront2]

Scott has just come up with the proper grommet. So, why not do as you suggested and make a bracket to put the 42-way engine connector either on the firewall or the back of the engine and run everything through the grommet to the ECU mounted on a bracket in the '85/86 location?

It would be pretty easy to measure everything and then set up a jig on the work table to get the wiring to length and soldered/heat shrunk. I think the connector will go through the hole in the firewall, although I'll have to check to make sure, but if it will the whole thing could be done on the bench and then installed on the truck. I think I'll want some kind of connector to let me disconnect from the PDB so installation will be easier, but that shouldn't be too hard.

Something like this:

Looks good, I would mount the body plug to a bracket, that way the longer section of wire will be on the engine so less bending as the engine moves under load/unload when driving. if you space it just far enough off the firewall, the wires from the PDC that go to the engine should be able to run behind it and then through so when disconnected there are no loose wires on that side to be in the way.

[Gary Lewis]

Looks good, I would mount the body plug to a bracket, that way the longer section of wire will be on the engine so less bending as the engine moves under load/unload when driving. if you space it just far enough off the firewall, the wires from the PDC that go to the engine should be able to run behind it and then through so when disconnected there are no loose wires on that side to be in the way.

Wait! "Body plug"? The oval at the firewall is Scott's grommet.

But maybe you mean the 42-pin connector that I show on the engine. And you are saying to mount it on a bracket on the firewall. That way there's no pull on the wiring going through the grommet and the wiring to the PDB from the engine can go behind the bracket and into the connector.

Like this?

[85lebaront2]

Wait! "Body plug"? The oval at the firewall is Scott's grommet.

But maybe you mean the 42-pin connector that I show on the engine. And you are saying to mount it on a bracket on the firewall. That way there's no pull on the wiring going through the grommet and the wiring to the PDB from the engine can go behind the bracket and into the connector.

Like this?

Yes, but turn it so the engine side is going straight into it, rather then turning 90°, make the turns in the stationary portion so there is minimal flexing of the wires.

[Gary Lewis]

Yes, but turn it so the engine side is going straight into it, rather then turning 90°, make the turns in the stationary portion so there is minimal flexing of the wires.

Good point. Should look like this then:

[85lebaront2]

Good point. Should look like this then:

YES! that is what I was thinking of and trying to get you to follow. Maybe the mind meld worked. Question, why keep a plug at the PDC? There are only maybe 4 or 5 wires that need to come from the PDC and they could be hardwired. If you need I can send you extra small plug sets if needed. FWIW, the 1987-1991 trucks used 4 of those 8 pin round connectors for the EFI to the engine including the AC compressor clutch. I don't know if I have some 42 way pairs, I know I have a front harness I used when I first set up Darth as a bank fired system so have the body side of the connector.

[Gary Lewis]

YES! that is what I was thinking of and trying to get you to follow. Maybe the mind meld worked. Question, why keep a plug at the PDC? There are only maybe 4 or 5 wires that need to come from the PDC and they could be hardwired. If you need I can send you extra small plug sets if needed. FWIW, the 1987-1991 trucks used 4 of those 8 pin round connectors for the EFI to the engine including the AC compressor clutch. I don't know if I have some 42 way pairs, I know I have a front harness I used when I first set up Darth as a bank fired system so have the body side of the connector.

Bill - The connector at the PDB is only for convenience. I didn't put one on the PDB on the passenger's side and I've wanted to take it out already to make a change, and that's not easy. So I want to put a connector on this one just in case.

As for which connector, I don't know how many wires I'll have going through it yet. Let's wait until I get things detailed out, probably this Fall, before figuring out which connector to use. But, I'll want one that can carry enough current on some pins for the fog lights and backup lights.

On the 42-pin connectors, I have at least two sets, including the one on the '96 harness that Mark sent me from CA, which is a full engine harness with sequential firing. So I'm good to go there, but thanks.

As for what I did today, I gave Big Blue an attitude adjustment. He now has the proper stance - level.

I removed the 2" blocks and installed the 4" ones using the 13" u-bolts from RuffStuff. It was actually pretty easy using the safety stand under the axle. On the passenger's side it was a piece of cake, but on the driver's side I had to pull the axle vent to allow the brake block to float up and not hurt the brake hose.

Anyway, the rear sits maybe 1/4" higher at the top of the wheelwell opening than the front, which is right where I want it. And, for reference, the front is at 40" and the rear at 40 1/4".