ignition question - pertronix + red coil + MSD 6AL

[CHR!S/DVK]

hope there are some guys around that have their electronics and ignition knowledge ready.
soon i will be running an engine that has a quite complex ignition system as i shortly found out.

i have a bosch 010 with pertronix ignitor, that just replaces the breaker points, right?
next, i have a bosch red coil, that has double the voltage output as a stock coil, right?
lastly, i also have a MSD 6AL, that again increases the voltage(on the primairy circuit) and gives mutiple sparks, right?

after some research i did today on all these wonderful parts i have i found out a couple of things.

- a bosch red coil needs an external ballast resistor of 1.8ohm(contrary to the blue coil that has an internal one)
- ballast resistors are perhaps for systems with breaker points?


my questions are:
- do i still need a ballast resistor? also with the use of the MSD? if so, where can i get it?
- can i still use my new bosch standard plug wires and ngk B6H plugs?
- what do you guys think of the setup?

[Brandon Sinclair]

Your red coil should not have a ballast resistor.  In fact many of the blue coils do not have the internal resistor either.  You just need to check it with an ohm meter to make sure.

If you run the Ignitor without a resistor it will burn out the pick up.  Since you are using a MSD ignition box you do not need the resistor though, however you may want to pick one up in case your box goes kaput on you so you can hook up the coil to the resistor and then to the distributor so you can get home.

I would get rid of those Bosch wires since some of them have a resistor in them.  You may want to check out the Taylor (CB sells them) or Magnecor or the Aurora wires (Aircooled.net sells them).  Also you may want to get an ignition rotor without the resistor since the box can burn it out over time (CB sells them and Aircooled.net does as well or you can make your own you just take your dremel and remove the carbon resistor between the center and tip and solder in a heavy gauge wire then use a 2 part epoxy to fill in what you removed).

[CHR!S/DVK]

thanks for your answer brandon!

i still have some questions as i want to fully understand this whole principle.

Your red coil should not have a ballast resistor.  In fact many of the blue coils do not have the internal resistor either.  You just need to check it with an ohm meter to make sure.

you mean my red coil doesn't have an INTERNAL resistor? how do i check the ohm value? i have an ohm meter, does the coil need +12V and ground when measuring?
what value should i get, and what to do when i get an other value?

If you run the Ignitor without a resistor it will burn out the pick up.  Since you are using a MSD ignition box you do not need the resistor though, however you may want to pick one up in case your box goes kaput on you so you can hook up the coil to the resistor and then to the distributor so you can get home.

to get things clear, i thought that a ballast resistor was to lower the voltage and to be bypassed when started to get a higher voltage and efficient starting?
what does the ballast resistor do in this case? and why does it burn the pick up when absent in this setup?

can i use a resistor AND an MSD box or does it make the system less efficient? i don't want to run with the risk of breaking my MSD box.

I would get rid of those Bosch wires since some of them have a resistor in them.  You may want to check out the Taylor (CB sells them) or Magnecor or the Aurora wires (Aircooled.net sells them).  Also you may want to get an ignition rotor without the resistor since the box can burn it out over time (CB sells them and Aircooled.net does as well or you can make your own you just take your dremel and remove the carbon resistor between the center and tip and solder in a heavy gauge wire then use a 2 part epoxy to fill in what you removed).

again, how can the box burn the resistor in the rotor? because of the increased voltage the MSD box(plus red coil) creates in the secondary circuit?



p.s. if anyone has any other comments, please add!
also i started a little search for a ballast resistor and found some of about $100 and one on a mercedes website for $30. it is just about the right ohm value, right?

[CHR!S/DVK]

also, the MSD instructions tell me i should ground the engine case to the chassis, how do i do that?

i once saw an engine case that has a wire connected with the use of a plastic sealed connecting on the side of the flywheel.

[Brandon Sinclair]

To check the ignition coil primary side resistance, have your ohmmeter set on the low scale and connect the ohmmeter leads across the primary terminals of the coil and read the ohms (ie one on + and one on - with all other wires disconnected).  A coil that requires a ballast resistor should read about 1.0 ohm. The stock Bosch VW coil or the Bosch HD Blue coil with the internal resistor will read 2.0 to 4.0 ohms.  Your red one should be around 1.0 ohms or less.

Running the ballast resistor with the MSD box defeats the purpose IMO.

Resistor in rotor info (since you have an 010 you can just get a rotor with brass like in the photo that Glenn sells and avoid doing any mods all together):
http://www.thesamba.com/vw/forum/viewtopic.php?t=351003
http://huelsmann.us/bugman/RotorTech.html
 
Here is the MSD resistor (around $8):
http://www.amazon.com/MSD-Ignition-8214-Ballast-Resistor/dp/B00029JL86

[CHR!S/DVK]

my coil point out 1.0 ohm, so i need the resistor? is the msd resistor the right one?


another thing, i have my smiths tachometer repaired and fixed for using electronic ignition(the pertronix), and with the use of the msd box i need get the signal from the msd box.
is this the same signal as from the pertronix so the tachometer doesn't need any other adjustment?