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I bought a trunk mout bat. kit from summit, if my camaro doesn't start on the first try the bat. seems to drain quickly, I have a high torqe starter on it and the motor has 10:1 compression, is the bat. too far back and the juice not traveling quick enough to keep starting the car? the lights and everything don't seem to dim any so that is what is making me think that the travel distance is just too far?
 

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Most of the time the universal type of kits have undersized wire and not enough wire for some installations.
I have dual batteries in my 73 in the trunk and I ran a 1/0 power wire from the battery positive post to the starter and then ran a 1/0 ground wire from the battery negative post to the engine block.
I used crimped on connectors that were also soldered after being crimped onto the wire.
I also made sure the ground connections were to bare steel on the engine and to the chassis of the car and not on top of painted surfaces.
I have seen some installations where with the trunk mounted battery the negative battery post has a short cable from it to the floor of the car only and the car cranks over slow but if they add a short jumper cable from the firewall to the engine block it cranks over better or faster.
You have to remember that the engine is somewhat electrically isolated from the body of the car as it is on rubber type motor and transmission mounts and the only electrical connection is either through ground straps or through things like the emergency brake cables and shifter linkage.
If your battery is grounded in the trunk and you think that is the problem, take some battery jumper cables and clip them between the engine block and the firewall. If it cranks over faster then either run a large ground cable from the engine to the battery or add some smaller ground straps between the engine and the chassis of the car.
Most stereo shops or welding supply places will either have in stock or can order large gauge wire and the terminals for them and sometimes it's actually cheaper to buy all the parts that you need to allow it to be customized to fit the vehicles needs.
Jim
 

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One thing about high current circuits is that the slightest amount of resistance will create a substantial voltage drop. For example, if you pull 100 Amps while cranking, a 1 ohm resistance can create a 100 volt drop (impossible right). A 0.1 ohm resistance will create a 10 volt drop.

Measure the voltage drop between the battery posts (do both + and - circuits in turn) and various points in the circuit. Have a friend crank the motor for you. (you might want to disable the ignition and block the throttle blades open) You'll figure out exactly where you're loosing voltage. Could be the terminals which could be soldered or recrimped. Chances are it's the wire, but good to be sure since wire is pretty expensive.
 
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