main power runs - coyote & busbar?

[toadster]

Running the main power lines for the engine bay, have positive and negative bus bars in the dash

as we're running the wire, the Coyote PDU is in the same place, it comes with a 250A fuse that hooks into the Coyote PDU main power

should a separate power feed go to the + bus bar with it's own breaker/fuse? or can we run two feeds out of the Coyote 250A fuse, with one lead to the PDU and 1 lead to the + bus bar?

173581

[edwardb]

I wouldn't do either. I wouldn't mess with the wiring for the Coyote. The 250 amp fuse provided by Ford Performance is for the Coyote system. Don't add anything to it.

For the second picture, I'm assuming you're using the bus bar to attach the main RF power wires plus other circuits where you want direct battery power. I've done the same thing. Either with a bus bar or just a simple feedthrough at the firewall. Everything downstream from there is fused (or should be) so already protected. Why add the 150 amp fuse before the bus bar? IMO, it's redundant and adds a point of failure that's not needed.

[toadster]

I wouldn't do either. I wouldn't mess with the wiring for the Coyote. The 250 amp fuse provided by Ford Performance is for the Coyote system. Don't add anything to it.

For the second picture, I'm assuming you're using the bus bar to attach the main RF power wires plus other circuits where you want direct battery power. I've done the same thing. Either with a bus bar or just a simple feedthrough at the firewall. Everything downstream from there is fused (or should be) so already protected. Why add the 150 amp fuse before the bus bar? IMO, it's redundant and adds a point of failure that's not needed.


ok - in seeing other posts, leave the 250A alone just for the Coyote PDU

as for the 2nd picture, the feed would come direct from battery to the bus bar so I thought the 150A fuse/breaker would be a safe thing to add to a direct line from the battery
I got the idea from some posts I've seen (I think yours on your Gen3 coupe?) where a 150A breaker between the alternator and dash?

[edwardb]

...as for the 2nd picture, the feed would come direct from battery to the bus bar so I thought the 150A fuse/breaker would be a safe thing to add to a direct line from the battery
I got the idea from some posts I've seen (I think yours on your Gen3 coupe?) where a 150A breaker between the alternator and dash?

Can't do too much more than repeat what I already said. As long as the circuits downstream from the bus bar are properly fused (for example, the RF panel where every circuit has a fuse) there's no reason to have another fuse on the input line. That would introduce a single point of failure for the entire car circuit on top of protecting individual circuits. Just doesn't make sense. The alternator mega fuse you mentioned is different. That's protecting the circuit from the battery to the alternator, which in the standard RF harness isn't protected.

[toadster]

Can't do too much more than repeat what I already said. As long as the circuits downstream from the bus bar are properly fused (for example, the RF panel where every circuit has a fuse) there's no reason to have another fuse on the input line. That would introduce a single point of failure for the entire car circuit on top of protecting individual circuits. Just doesn't make sense. The alternator mega fuse you mentioned is different. That's protecting the circuit from the battery to the alternator, which in the standard RF harness isn't protected.

Thanks Paul - found this other thread where you explained things as well, sorry must have been tired last night ;)
https://thefactoryfiveforum.com/showthread.php?33549-Please-critique-my-coyote-wiring-plan-(diagram-included)

always thankful for your help!

[Gizmosrcool]

Toaster. Are u using a cutoff switch? How about something like this.

Battery ——— > cutoff switch unswitched leg
Cutoff switch unswitched leg ——— > anything needing to be hot all the time. Or to a mini bus bar.
Cutoff switch switched leg ——— > coyote fused circuit
Cutoff switch switched leg ——— > bus bar. No fuse.

No fuse is needed on the bus bar if all the circuits are individually fused.

I’m planning this approach.

Tom

[JohnK]

I used a cutoff switch as a distribution point, but took a slightly different approach. I tried to copy Edwardb's approach, which makes sense to me:

Bottom left - 2 ga. wire from battery

Bottom right - outgoing wire (unswitched) to Coyote master fuse and then on to coyote PDB.

Top left - 4 ga. wire (switched) running back to starter

Top right - switched power to bus bar on firewall and RF harness


https://thefactoryfiveforum.com/attachment.php?attachmentid=151518&d=1627956429

[toadster]

thanks guys - no cutoff switch in my build but makes sense now - thanks!

[Gizmosrcool]

JohnK explained better than I did and the picture is spot on. Very nice.