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Help - Trunk Battery Cable Routing

RRDon

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I'm routing the battery cable from the trunk to the starter on my 68 Road Runner 383 four speed. I ran it from the trunk along the driver's side following the wiring harness for the tail lights.

Everything was going well until I got to the firewall. Hmmm, not sure where to run it through. I could use the speed-o-meter cable hole but then what to do with that cable. Things look pretty tight in that area and I’m not thrilled with the idea of drilling another hole somewhere but I don’t see any way around it. It’s not a numbers matching car so drilling another hole wouldn’t be the end of the world.

My question is for those who have done this before and what did you guys do and what did you find worked best. Also what should I avoid or be aware of (other than making sure the battery cable is protected and can’t rub or short out anywhere).
Front Correct.jpg


Any advice and info would be most appreciated. Thanks guys. RR Don
 
I added a couple extra photos for you guys. I know I always enjoy seeing your actual cars when I read your posts. :)
 
IMO you should run the cable UNDER the car to the starter.The route of the cable is done with the law of common sense!

BTW,,,that car is GORGEOUS!!!!
 
Yeah, I thought about running it under (I did that on my 70RR race car) but I wanted to protect the cable as much as possible from heat an the elements. I will have to drill through somewhere regardless.
Thanks for your kind words about the car ;))
 
You don't want that big + cable inside the car more than it needs to be. I ran mine under the back seat and out one of the floor plus then tied it to the brake line. In to the front frame rail inside a length of rubber/plastic tubing for protection the out the frame rail close to the starter.
 
Like the above I went thru body plug in trunk by the shocks, no drilling required.
 
Run the cable under the car. You can encase it in braided tubing. Then get a Cole Hersey 300 amp solenoid. Run the wire to a post in the engine compartment then direct to the hi amp pole on starter. The Cole Hersey is located in the trunk. Then you only have power going thru the cable when your operating the starter. Run the key start and run to the trunk and operate the solenoid for starting only. You will need a 10 gauge wire going to the trunk inside the car from the alternator to the Battery. The Negative pole on your battery goers thru a 300 amp battery disconnect. Install a fusible link 10 gauge between ten gauge and positive on battery.

We are trying to help you. 40 years of Knowledge being given to you without the 500.00 fee for knowledge. Make good use of this.
 
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I run that cable along the driver side sill plate and out the clutch hole/grommet in firewall. Only time the cable is hot is when starter is running via solenoid at rear. No need to be concerned with that being hot all the time and under the car.

Routing depends on how the cable is used. I know of cars that have it hot all the time and running same route as I mentioned.
 
Just wanted to say "Thanks" to you guys for the helpful advice and comments.
I found a way to run using a thru body plug. Did not need to drill any holes. :)
 
Run the cable under the car. You can encase it in braided tubing. Then get a Cole Hersey 300 amp solenoid. Run the wire to a post in the engine compartment then direct to the hi amp pole on starter. The Cole Hersey is located in the trunk. Then you only have power going thru the cable when your operating the starter. Run the key start and run to the trunk and operate the solenoid for starting only. You will need a 10 gauge wire going to the runk inside the car from the alternator tot he Battery. The Negative ole on your battery goers thru a 300 amp battery disconnect. Install a fuseable link 10 gauge between ten gauge and positive on battery.

We are trying to help you. 40 years of Knowledge being given too you without the 500.00 fee for knowledge. Make good use of this.
Where under the car did you run the battery cable? Inside the bumper and along the frame? If you have pictures that would be great?
 
Here is what I did. I ran the cable through the car and up out the firewall as I drilled a hole in the firewall for it. But I also mounted a Ford style starter solenoid in my trunk so that cable is only hot while the eng is cranking as I did not want a hot battery cable under my carpet all the time. Now my battery cable ends have a post on them so I can run more then one battery cable so I ran another pos and neg cable under the car up to post on the firewall and thats my hot that feeds the car as I used a 70 amp fuse at the battery plus it still has the factory fuse link at the firewall to protect that circuit. I also ran a ground from the post on the firewall to the eng and the body. And a new alt output wire with a 100 amp alt. But if you run it under the carpet I would not leave it hot all the time and since you cant run a fuse or fuse link on the starter cable wire thats why I use the solenoid in the trunk so its only hot when cranking. Then run another circuit like I did to feed the car. Also at the starter I just put a small 14 gauge jumper wire from the solenoid terminal on the starter to the starter hot post so it cranks as soon as the solenoid in the trunk sends volts to it. Good luck , Ron
 
Recently somebody post pics about what MaMopar made on WO23 ams RO23 66/67 Hemi cars, and they run the wire inside the cab. IMHO, that's what I would made.
 
Here is what I did. I ran the cable through the car and up out the firewall as I drilled a hole in the firewall for it. But I also mounted a Ford style starter solenoid in my trunk so that cable is only hot while the eng is cranking as I did not want a hot battery cable under my carpet all the time. Now my battery cable ends have a post on them so I can run more then one battery cable so I ran another pos and neg cable under the car up to post on the firewall and thats my hot that feeds the car as I used a 70 amp fuse at the battery plus it still has the factory fuse link at the firewall to protect that circuit. I also ran a ground from the post on the firewall to the eng and the body. And a new alt output wire with a 100 amp alt. But if you run it under the carpet I would not leave it hot all the time and since you cant run a fuse or fuse link on the starter cable wire thats why I use the solenoid in the trunk so its only hot when cranking. Then run another circuit like I did to feed the car. Also at the starter I just put a small 14 gauge jumper wire from the solenoid terminal on the starter to the starter hot post so it cranks as soon as the solenoid in the trunk sends volts to it. Good luck , Ron

THIS IS AN EXCELLENT SUGGESTION.... By energizing the starter feed only while cranking eliminates the possibility of short circuits during normal operation. The Ford style solenoid has adequate ampacity to handle the chore. It is my suggestion to use # 1/0 AWG (minimum) stranded copper wire, similar to welding cable for both the feed to the solenoid, from the solenoid to the starter and the battery ground to the frame. Because the starter draws 400+ amps during cranking (even more when the engine is cold or with high compression ratios), the # 1/0 (or # 2/0 AWG) will minimize the voltage drop from battery to the starter. Remember, the starter needs BOTH an adequate supply of both voltage and current during cranking to maximize the torque produced. Use the largest size wire you can afford. Just my opinion of course.
BOB RENTON
 
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