I just bought the Pertronix kit (Pertronix Ignator and 40000 volts coil) for my 280S, 1969. I had a look at my distributor and coil and have a couple of questions regarding the installation procedure. Considering that this is new to me, I want to make sure that I don't do anything stupid.
My current coil (Bosch blue coil) is installed as follows:the negative wire goes to the distributor and the positive wire is attached to a device (resistor ?) which is connected to a wider wire that goes through the firewall, on the driver side of the car. I understand that if I use the Flamethrower coil, I need to eliminate any existing ballast resistor.
Does my car have a ballast resistor? Where is this resistor? Is it the device to which my coil's positive wire is now connected? In order to eliminate the resistor, do I just disconnect the two wires on each side of the resistor and attach them together?
Also, regarding the magnetic ring, I noticed that it has a white dot painted on its top. Do I need to install the magnet with the white dot side down or up? Is there any difference?
Thanks.

__________________
280S, 1969
250C, 1972

Here's a good basic run-through:
http://www.mbzponton.org/valueadded/maintenance/ignitionpert/ignitionpert.htm

I too have a 280s with a Pertronix system. It improved my engine's ignition significantly.

Your ballast resistor is mounted on left hand side of the engine compartment wall, in front of the distributor. It's a white rectangular block about the size of a pack of gum with a few wires running to it.

Pertronix (who has good customer service via telephone btw.) told me that the 1.5 ohm coil requires the resistor, but with their 3.0 ohm coil, it should be bypassed. My car wouldn't run with resistor not wired in line, but I moved the wire running from the coil to the resistor to the other resistor post, where the voltage is not reduced.

Don't know about the white dot on the magnet...

Thanks, Joe. My resistor is in the same place. It only has 2 wires running to it: one running from the positive terminal of the coil and another running from the firewall.
I have an additional question. You mentioned another resistor, where the voltage is not reduced. Where is this other resistor? Except from the primary wire that runs from the top of the coil to the distributor cap and the positive wire running to the resistor, the other wire that I see runs from the negative terminal of my coil to the distributor. I don't see another resistor connected to the coil.
Do I have to leave the negative wire that connects the coil to the distributor or should I disconnect it?
I'm sorry if my questions sound dumb, but I want to double check before making stupid things.
Thanks.

__________________
280S, 1969
250C, 1972

Not dumb questions at all. I moved my wires to the other post of the same resistor, not a second resistor. The resistor has two threaded posts, I moved the wire from one to the other.

I also searched the 113 forum at

http://www.sl113.org/forums/search.asp

using the terms 'ballast' and/ or 'pertronix' and found more info than I had via this forum.

I installed the Ignitor and the Flame Thrower coil. I just followed the instructions and everything went well. It's a great upgrade and my car now runs smoothly.
Thanks for your help.

__________________
280S, 1969
250C, 1972