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Discussion Starter #1
I getting ready to install a new MSD ready to run distributor and the instructions say "the MSD Extra Duty Distributor is designed to work with full voltage at the coil". Sounds like I need to bypass the resistance wire. Any ideas on the best way to do that? Should I splice into the wire with a copper strand wire somewhere near the bulkhead connector or run a new wire with the proper spade terminal to plug into the bulkhead connector after removing the resistance wire.
 

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Option B

"run a new wire with the proper spade terminal to plug into the bulkhead connector after removing the resistance wire."

The terminals are available at Napa.
 

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Or Option C.
Run another wire from a switched terminal on the fuse block. Tie back and tape off the original resistor wire.
 

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Discussion Starter #5
Thanks for the suggestions.

As a follow up… in another recent post topic: External Resistance Coils", the comment was made, "The external resistor is there to step down the voltage applied to your coil. Coil operating voltage is in the neighborhood of 8 to 9 volts as I recall. (anybody correct me if I am too far off here) Your system is 12 volts and the engineers have determined that 12 volts is too much for the coil in your car, or rather too much for the points in your ignition system. So they step the voltage down a bit".

Does this mean that the coil is "expecting" something less than 12V and if I bypass my resistor wire I may cause some problems?
 

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Looks like some of Charbilly's typing you quoted. He's correct for a standard GM points car hook-up. Doesn't MSD's diagram show a full 12 volts to the distributor and then a wire from the distributor to the coil? They already took care of it. Follow their wiring instructions.
*EDIT*
If you are unsure about their distributor or have a question about MSD, they have a tech line www.msdignition.com

[This message has been edited by John_Muha (edited 04-17-2002).]
 

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Discussion Starter #7
Thanks John....I spoke to MSD tech support a couple of days ago and they were helpful but what I really wanted from this forum is some "real life" suggestions and you guys came through (as you always do).
 

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70SS_69Z The voltage stepdown only applies to breaker point systems. The coil doesn't particularly care what voltage it sees. Until you overload its design base it will just make more secondary voltage as you feed it more primary voltage. The points do because of the voltage spikes inherent in the system. If you look at your points when you crank your motor over with the ignition switch in the run position you will see a spark occur everytime the points open. That spark is responsible for point erosion from the + to - faces of the points over time. With out the condenser in your distributor that spark would be significantly more powerful and cause more damage to your points.


There is a long explanation for why there is a spark there in the first place and why the condenser is needed. No surprise here but it is not as simple as it seems. I am not going to attempt that without further research to get my facts straight AND unless somebody asks.

[This message has been edited by charbilly2001 (edited 04-18-2002).]
 

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Discussion Starter #9
Charbilly...thanks for the info. Now I not only know how to bypass the resistor wire but why it should be done in my application.
 
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