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I recently put a set of Dougs headers on my 66. I am now installing the new Robbie Mac starter with the rotating solenid.
Has anyone run this combo and found a good way to run the wiring? It looks like the best way is to still run it through the headers similar to the way the wires previously went through the manifold.
 

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Since I switched to Summit mini-starters, I mount a Ford type remote solenoid on the firewall, then run only one main wire to the solenoid on the starter. Then you add a short permanent jumper wire from the main terminal to the start term on the starter. This way, current is going to the starter ONLY when you're trying to start the engine.

The solenoid I bought for my current '80 Bird bracket car is a Cole-Hersee brand.

https://www.amazon.com/Cole-Hersee-24037-Intermittent-Solenoid/dp/B001FQL40S/ref=sr_1_6?keywords=cole+hersee+intermittent+duty+solenoid&qid=1552318701&s=gateway&sr=8-6

Some racers use this one.

https://www.amazon.com/QuickCar-Racing-Products-50-430-Solenoid/dp/B003TTYSH0#customerReviews

Back in the old days, I bought a cheap one at my NAPA store, & it stuck in the on position. Not good !
 

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I run the Robb Mc starter and use the Ford “solenoid” switch on the fender like BigD. It really is a great method as that Ford “Relay” or magnetic switc delivers major amps to the starter solenoid and is only hot when cranking.

Now with the RobbMc starter you cannot jump the wire on the starter.....you use a four terminal switch mine is an echo in from Napa and you run the I terminal to the S switch on the solenoid, of course the hot battery cable is the same.

RobbMc has it in his instructions on the starter, his stuff is awesome and you can clock the solenoid 360, I run mine under the starter heat rises and solenoid stays cool.

Also if you run the Fender switch you just run those two wires straight down behind the fuel pump and between the motor mount and the engine.:nerd::nerd:
 

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Thanks BigD May have to switch to a cole hearse,...I see they have a four terminal with 200 amp as well. Thanks
I thought about buying a "continuous duty" model, like those used on electric golf carts. But after doing some research, I found that a car starter can pull more amps than those solenoids are rated for. The kind that are best for car starters will stand more amps, for a short period. At least that's what I got from what I read online. Anyhow, the 3-term Cole-Hersee I bought works just fine crankin my 455 bracket engine, with a Summit mini-starter.

https://www.elreg.com/blog/continuous-duty-solenoids-vs-regular-starter-solenoids-why-they-arent-interchangeable/

https://aviondemand.com/insider/starter-solenoids-and-continuous-duty-solenoids/

http://www.wellsve.com/ss_disclaimer.html
 

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I am not quite convinced that adding a "remote" solenoid (ford type) really does solve the problem of standard starter/solenoid heat soak. If a starter does suffer from this build up of heat thereby increasing the resistance of its components, then to maintain 12 v, the battery must supply increased amperage to complete the start up process.

Just because you have a 600 CCA battery, the starter only requires 200 amps to work. Then what does the "remote" solenoid do to offset this? It still has to make a connection thru the heat soaked starter solenoid. GTO's do not have direct connect starters??

Minimum resistance for battery voltage/current to reach the starter solenoid is thru a fresh, clean, ample gauge wire connected directly to it. Other connections that interrupt that path just add to the resistance of the circuit. (Of course and equally grounded, minimal resistance bonded connection back to the negative side of the battery is mandatory.)

Using ohms law, and assuming: a. battery voltage = 12V, b. starting current = 200 amps. That means the over all circuit resistance is 0.06 ohm. (R=V/I 12/200 = 0.06 ohms). Not much resistance, for all practical results almost a dead short.

Another way to look at it is, how is the starter current limited with an increase of resistance? (I=V/R) 12 volts @ 0.06 ohms = 200 amps. Increase the resistance by just a tiny fraction to say 0.1 ohms @ 12 volts reduces it to 120 amps i.e. slower cranking.

https://www.knowyourparts.com/technical-resources/starting-and-charging/starter-will-not-crank-when-hot-heat-soak/


The solution is to install either a heat shield on the starter or go to a newer style i.e. Robb Mc or similar type. These manufactures do not recommend using a jumper to the "S" terminal to eliminate the single wire from the ignition. (We all know that this is on paper and that a battery will drop below 12 volts during cranking on a "normal" mild day so the results of the math will change)

This is my reasoning/understanding, YMMV

Just an added note, on my 65, the alternator output has a wire that runs down to the starter and connects to the big lug making a connection via the big red wire to charge the battery.
 
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