WHYDTYTT: What Have You Done To Your Truck Today?

[kramttocs]

Thanks, Gary! I had looked into the EVTM pages, but I saw that the resistor wire said "DuraSpark only", so I didn't really know if that applied to my vehicle. My body harness is not the original 1986 one, but one that I got from an '85 donor. I traced it all out to make sure that all the necessary wires were there and in good condition, but I didn't think to make a note of any extras that were there.

The documentation for the Edelbrock system very strongly specifies that it needs a full 12v in start and in run. The reason I am asking specifically about wires in the c-321, c-323, and c-325 connectors is that I would love to not have to hack into the body harness again. I guess since I no longer have the stock system in, if it came down to it, I could run a normal wire in place of the resistor wire.

The resistor wire is tucked up pretty high in the dash harness.

Before going that route and if willing to run a wire through the firewall, I'd take a look here

[Gary Lewis]

Thanks, Gary! I had looked into the EVTM pages, but I saw that the resistor wire said "DuraSpark only", so I didn't really know if that applied to my vehicle. My body harness is not the original 1986 one, but one that I got from an '85 donor. I traced it all out to make sure that all the necessary wires were there and in good condition, but I didn't think to make a note of any extras that were there.

The documentation for the Edelbrock system very strongly specifies that it needs a full 12v in start and in run. The reason I am asking specifically about wires in the c-321, c-323, and c-325 connectors is that I would love to not have to hack into the body harness again. I guess since I no longer have the stock system in, if it came down to it, I could run a normal wire in place of the resistor wire.

Even the 5.0L EEC has the same resistor. But at 1.1 ohm, there will be VERY little voltage drop.

For instance, let's assume that they are just sensing that you have voltage in Start. Let's say they pull in a relay that takes 250 ma in the coil. E = I*R do E = .25 * 1.1 = .275 volt drop. So if the battery pulls down to 11v in starting the system would see 10.725v and the relay would pull in easily.

But if it is electronic, meaning a transistor is sensing it there won't be enough current draw to cause even that much voltage drop.

So is that wire sensing or using voltage?

[Nickelplate]

Even the 5.0L EEC has the same resistor. But at 1.1 ohm, there will be VERY little voltage drop.

For instance, let's assume that they are just sensing that you have voltage in Start. Let's say they pull in a relay that takes 250 ma in the coil. E = I*R do E = .25 * 1.1 = .275 volt drop. So if the battery pulls down to 11v in starting the system would see 10.725v and the relay would pull in easily.

But if it is electronic, meaning a transistor is sensing it there won't be enough current draw to cause even that much voltage drop.

So is that wire sensing or using voltage?

That is actually a pretty small voltage drop, so I bet it would be fine. I have tried to get Edelbrock on the phone for the past few business days and gave up after 30 minutes on hold each time. But if I could get in touch with them, I could see if it must be 12v exactly. I will trace it out and see if it just goes to trigger the ECU relay, or if it goes to the ECU itself. If it goes to the relay then I am sure that will be fine.

The instructions state:

"Connect the Pink/Black IGN switched wire on the main harness to a +12 Volt switched power source that provides +12 Volts when

the key is both “ON” and “CRANKING”.

NOTE: It is critical that the switched +12 Volts to the IGN switch wire is constant during cranking. This is a common issue on

vehicles with no start or hard to start issues. Do not connect this to the positive side of the coil."

 

[ArdWrknTrk]

That is actually a pretty small voltage drop, so I bet it would be fine. I have tried to get Edelbrock on the phone for the past few business days and gave up after 30 minutes on hold each time. But if I could get in touch with them, I could see if it must be 12v exactly. I will trace it out and see if it just goes to trigger the ECU relay, or if it goes to the ECU itself. If it goes to the relay then I am sure that will be fine.

The instructions state:

"Connect the Pink/Black IGN switched wire on the main harness to a +12 Volt switched power source that provides +12 Volts when

the key is both “ON” and “CRANKING”.

NOTE: It is critical that the switched +12 Volts to the IGN switch wire is constant during cranking. This is a common issue on

vehicles with no start or hard to start issues. Do not connect this to the positive side of the coil."

Right, because the coil wire is going to flicker as the coil saturates and then the field collapses.

But the fuel pump lead gets full voltage while cranking and reduced power in run.

(of course the alternator is likely to bring the whole system voltage up to ~14.5) so "reduced" or resistor power while the truck is running is going to be over 12 in any case.

[Angelo Voltura]

Right, because the coil wire is going to flicker as the coil saturates and then the field collapses.

But the fuel pump lead gets full voltage while cranking and reduced power in run.

(of course the alternator is likely to bring the whole system voltage up to ~14.5) so "reduced" or resistor power while the truck is running is going to be over 12 in any case.

Did a few minor upgraded over the last few days. Changed the headlights which are now removable bulb H4 sealed beams w/ projectors wired up on relays, put rear center caps back on, installed rain visors on the doors off a parts truck and a few other small things. Still need to get the cab lights on, stone guards on the headlights, my rear pipe bumper and 2 more KCs on the roll bar then I'll be happy.

[Gary Lewis]

Did a few minor upgraded over the last few days. Changed the headlights which are now removable bulb H4 sealed beams w/ projectors wired up on relays, put rear center caps back on, installed rain visors on the doors off a parts truck and a few other small things. Still need to get the cab lights on, stone guards on the headlights, my rear pipe bumper and 2 more KCs on the roll bar then I'll be happy.

Looks good, Angelo.

Didn't know you could go with different headlights that way. So these don't hold water like a lot of them do? And they hadn't gone to relays by then?

 

[ArdWrknTrk]

Did a few minor upgraded over the last few days. Changed the headlights which are now removable bulb H4 sealed beams w/ projectors wired up on relays, put rear center caps back on, installed rain visors on the doors off a parts truck and a few other small things. Still need to get the cab lights on, stone guards on the headlights, my rear pipe bumper and 2 more KCs on the roll bar then I'll be happy.

Aussie headlamp conversion?

[Angelo Voltura]

Looks good, Angelo.

Didn't know you could go with different headlights that way. So these don't hold water like a lot of them do? And they hadn't gone to relays by then?

Yes, its a factory Australia only conversion back to sealed beams. OBS Solutions got ahold of a mint set a few years ago and started repopping them for the US market since there arent too many adtermarket lights for Bricks available. Then I bought aftermarket sealed beam housings with projectors built in and removable H4/9003 bulbs. I could easily put H6054 sealed beams back in, they have a plate that uses the factory adjusters and buckets and then that just has the usual trim ring and 4 screws to hold a sealed beam in.

This truck didn't have relays for the headlights, it's still wired like a bullnose just has 9004 bulbs. So I bought a relay harness and then cut the pigtails off for a standard 3 prong plug and soldered them in. I just put some cheap Sylvanias in them to get them working and the light output is far better than the factory housings, but I think a good set of 100w bulbs is in order.

[grumpin]

Looks good, Angelo.

Didn't know you could go with different headlights that way. So these don't hold water like a lot of them do? And they hadn't gone to relays by then?

Yes, its a factory Australia only conversion back to sealed beams. OBS Solutions got ahold of a mint set a few years ago and started repopping them for the US market since there arent too many adtermarket lights for Bricks available. Then I bought aftermarket sealed beam housings with projectors built in and removable H4/9003 bulbs. I could easily put H6054 sealed beams back in, they have a plate that uses the factory adjusters and buckets and then that just has the usual trim ring and 4 screws to hold a sealed beam in.

This truck didn't have relays for the headlights, it's still wired like a bullnose just has 9004 bulbs. So I bought a relay harness and then cut the pigtails off for a standard 3 prong plug and soldered them in. I just put some cheap Sylvanias in them to get them working and the light output is far better than the factory housings, but I think a good set of 100w bulbs is in order.

Nice looking truck! Looks like fun!

[Nickelplate]

Did a few minor upgraded over the last few days. Changed the headlights which are now removable bulb H4 sealed beams w/ projectors wired up on relays, put rear center caps back on, installed rain visors on the doors off a parts truck and a few other small things. Still need to get the cab lights on, stone guards on the headlights, my rear pipe bumper and 2 more KCs on the roll bar then I'll be happy.

Looks great! I love the roll bar.