Routing battery cable to starter question

[lmccoll2]

What is the best to route the battery cable from the battery to the starter on a SBC? My car is a 74 Camaro, right now I ran the cable over to the radiator and back down the inside frame rail and over to the starter so it wouldn't get next to the headers. How does everyone else route the battery cable?

[katman]

On my 79 I mounted the battery in the trunk but I mounted a Ford solenoid on the firewall straight up from the starter. Several reasons for this. It gets all the wires of the solenoid except the main battery cable. You run a shorter heavy cable from the Ford solenoid to the starter solenoid and a short jumper from there to the start terminal. With your setup, if the battery cable shorts out on the headers, you have a fire hazard. With my setup, unless I hit the start button, there's no power on that cable down by the headers. On another note, when I have to remove the starter, I just pull the wire off at the Ford solenoid and it comes out with the starter. I don't have to hold up the starter and try to remove all those wires while laying on my back.

[lmccoll2]

So, you run the starter cable down the firewall? Sounds like it goes down the fire wall behind the distributor and on down to the starter much like the OEM routing. Sounds good.

I like the idea of the short cable too that can come off the starter. I am in progress of moving my battery to the trunk and was trying to find the best way to get the cable to the starter. Right now it goes to the radiator and then back along with the trans cooler lines, kind of a long route.

[dwilliams]

Don't be afraid to upsize the battery cables. Light weight is nice; a car that starts cleanly when heat-soaked in the pits is nicer.

Some welding supply or hydraulic shops may have the proper crimping tool for battery lugs. You can also solder them using a propane torch.

Belden makes collet-type cast copper terminals - just strip the wire, slide it in, and wrench it down. Since the price of ordinary lugs and ends has skyrocketed lately, the price doesn't look so bad any more.

Ground the battery to the starter. Right there, where the maximum amperage needs to go. Seeking a ground through painted junctions, spot welds, rusty iron, and bolted connections works, sort of. A proper ground works better.

[bulitpruf]

A ford solenoid as wired in the above post will cause the pinion gear to remain in the flywheel longer than necessary. This causes the pinion to be driven by the engine at hi speeds. How Hi? about 36000 rpm at 2000 engine rpm. This is why the pinion return spring on Hitachi starters explode. At this rpm they expand and rub the starter housing, turns blue and falls apart. A ford solenoid on a permanent magnet starter is a real no no. They tend to stay in the flywheel a very long time.

[BCjohnny]

A ford solenoid as wired in the above post will cause the pinion gear to remain in the flywheel longer than necessary. This causes the pinion to be driven by the engine at hi speeds. How Hi? about 36000 rpm at 2000 engine rpm. This is why the pinion return spring on Hitachi starters explode. At this rpm they expand and rub the starter housing, turns blue and falls apart. A ford solenoid on a permanent magnet starter is a real no no. They tend to stay in the flywheel a very long time.

Couldn't agree more. The back EMF generated by the starter armature slowing down is sufficient to hold the solenoid in, until it stops acting like a generator, which can take a number of seconds.

And if the RCD (sprag) grabs for a split second the starter armature can see around 120,000 rpm, depending on reduction ratio. As a result you don't tend to strip them, more pour the contents onto the bench..........

Wiring through a remote solenoid in the manner described may work, but due to the dis-engagement delay, it's not best practice, to say the least.

By all means use a remote solenoid, but not the "jumper" cable on the starter. Controlling both the starter and remote solenoids directly from the switch is a better option, and gets the permanent live away from the headers. Depending on which solenoid switches first this may lead to a (slight) cranking delay, though of no real importance.

And battery cable sizing is no where near as important with a pmgr/geared starter as a conventional starter.

John.

[lmccoll2]

Thanks for all the info on the starter. I hadn't thought about the Ford solenoid causing the starter drive to stay in too long. I think I will run a start wire to both. Thanks.

[katman]

Strange, I know 5 or 6 people with that set-up and NO PROBLEMS!

[bulitpruf]

It all depends on the engine and the guy starting it. If it starts easy at a low throttle setting and goes to idle there is no problem. If the engine is hard to start and has to be winged to 2 or 3 thousand rpm before settleing down to an idle, good bye return spring. And the damage can be done with one start. We been doing starters fo 25 years making our own for 10 we've seen a ton of broken springs and almost all had a ford solenoid in the circuit.