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Battery to trunk, 70 road runner, inline fuse??

70 RR

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Location
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I am moving my battery to the trunk and I am wondering if its a good idea to run an inline fuse on my battery cable. I am using 1 gauge wire and I am routing it through the wire tunnel on the passenger side and through the firewall. I want to protect my car from turning into a 3,900 pound arc welder! Any good advice on this subject would be much appreciated. Also, if fuse is advised, what amp fuse would be best? Thanks!
 
I would route cable under car, use a heavy Duty Battery disconnect in the Negative cable. Then get a Cole Hersey Solinoid and so the battery cable is only energized when the Starter is operated. Mad Electric has an interesting article on this. Keep the Negative cable very short.
 
didn't fuse mine. just protect it well.
 

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electrical info

Wow, 2059 this install looks great, neat, functional. dang near perfect as I would like mine to look. hope you don't mind if I use some of your ideas, thinking and pictures on my 68 RR.
I would like to see other pics of your electrical as I know the rest of the electrical will look to be the same high quality.
Snake Oil, you need to really look at these pics. I also am not fusing my electrical main and using the binding posts in the under dash area, and on the lower outer firewall. fusing branch (individual) circuits like lights, ignition, and smaller circuits, but not main cable.
I am using DLO (diesel locomotive cable) for my main cable. it is rated for 600 Volts and has two layers of insulation, and inner and outer. the insulation is Hypalon that is flame proof. the outer insulation will protect from abrasion, and still leave the inner electrical insulation intact. Yeah, I tend to over-engineer everything (I am an electrical and mechanical engineer).
keep the pics and questions coming.
thanks
pt in tennessee
k
didn't fuse mine. just protect it well.
 
From what I understand, if you have a trunk mounted battery and plan on taking the car drag racing, the cable must be routed under the car. Routing it inside the car is not allowed.

I agree that 2059's install is super neat and nice. I am just not sure he would ever be allowed to run that car on the track. Something to consider depending on your plans for the car.
 
Thanks for the photos 2059, your work does look very nice. I am not using the car for racing, just a very strong street car that I may take to the track now and then. I really wanted to avoid running the power cable under the car to make for an easier install. I do worry however, that no matter how careful you are there are many sharp edges in these old machines and couple that with vibration spells disaster. I just want to protect my investment and have piece of mind at the same time...... Call me paranoid but I believe in Murphy's Law.
 
A fuse in the main battery line is not a good idea; a very hot or very cold, hard cranking engine can pull a coupla hundred peak amps from the battery. So any fuse become so large as to become pretty useless. Ditto for fusible link to the satrter linf; it's OK for the charging but not in series with the starter. Good protection and a very large wire is the right way to go; 1ga is a bit small IMO for a large engine than can have hot start problems; I would be looking at 0 or 00. AND, your ground return to the engine compartment is just as critical.

I have used EMT conduit in a race car before with an internal routed battery line.
 
I am going to add a relay to the power wire and make sure that the route to the starter is clear of sharp edges. That should do the trick. Thanks to all for your input, it is much appreciated.
 
There is NO such thing as over thinking the main feed wire. I have seen sparks when a floor jack shorted the wires before, the worker did not know about the wiring. No highjack if still on same subject. IMHO.
X2 on increase wire size from 1. 1 is good if under 4 feet.
 
Simple quick question ,I'm just wondering why people move the battery to the trunk in the first place, is it just preference or do some believe there is an advantage in the relocation? Just wondering what the necessity of the move is especially with all the extra wire and cost involved to do so.Thanks and God bless.
 
Weight transfer. Instead of 45lb being out front, it's behind the rear wheels. For handling and drag racing, this is significant, because -45 lbs off the front is -1.2%. +45lb out back is +1.2%, but because it's behind the rear wheels, it equates to more like 1.5%, so you get a shift of almost 3% of body weight for very little $$. Only other way to get that kind of weight transfer is reducing about 100lb off the front, which is heads, fiberglass hood and bumper, which costs $$$$.
 
From what I understand, if you have a trunk mounted battery and plan on taking the car drag racing, the cable must be routed under the car. Routing it inside the car is not allowed.

I agree that 2059's install is super neat and nice. I am just not sure he would ever be allowed to run that car on the track. Something to consider depending on your plans for the car.

hsorman, ya, you're likely right on the regulations. Like 70RR said, I too, built the car for street use. I don't race because DW doesn't want me too. Besides, at my age, my reaction time would probably be about... 3 days... :)
 
I just finished wiring up my battery. I used a Ford solenoid to route my 1 gauge wire through and on to the starter. I am running 8 gauge from the battery with an in-line 60 amp fuse (might be too big a fuse but I can change it) to my starter relay on the firewall to power the rest of the car and then a 14 gauge wire from the relay to the small terminal on the starter. I didn't want to wire under the car so its all internal (except the ground to the sub-frame). I followed this wiring diagram from Mad Electrical:

View attachment 190769Trunk 1 - Copy.jpgtrunk 2 - Copy.jpg
 
I just finished wiring up my battery. I used a Ford solenoid to route my 1 gauge wire through and on to the starter. I am running 8 gauge from the battery with an in-line 60 amp fuse (might be too big a fuse but I can change it) to my starter relay on the firewall to power the rest of the car and then a 14 gauge wire from the relay to the small terminal on the starter. I didn't want to wire under the car so its all internal (except the ground to the sub-frame). I followed this wiring diagram from Mad Electrical:

View attachment 190769View attachment 190770View attachment 190771



Thats what I did is put a Ford starter solenoid in the trunk. That way the starter cable is only hot while cranking. I ran mine inside the car also and did not want my battery cable to the starter hot all the time. I also ran the hot feed just like you did with a 70 amp large fuse in that. Ron
 
Hey 451, I can't help you on the circuit breaker, all I can tell you is I did some research and I found some really good info on the Mad Electrical site. I didn't want to take any chances not protecting my car.
 
That circuit breaker is made for audio amp transients, not for power. Any 300 amp breaker for power use is going to cost a lot more than $11
 
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