MSD upgrade from CDI question

[9dreizig]

Ok so I'm replacing my CDI with a MSD 6A that I had running fine in my other 930.

Here's the wiring that I am trying but I am getting no spark.

according to the MSD instructions the Violet/green wires come from

Here's a diagram of what I've done and am wiring into the original connector.

I know the tach out is correct, as is the 12V and grounds.. the only thing I can think of is should I not be using the violet/ green wires but rather the white wire into the MSD ?

The MSD manual says use the violet / green wires for a distributor with a mag pick up and the white wire for points?? ( I may have just answered my own question but wanted to run it by the brain trust

[timmy2]

In some cases you need to swap violet and green for some MSD units.
(7 and 31d)
Other than that, confirm switched and constant power are there.

[T77911S]

timmy is one of the few that would that.

he IS correct. you HAVE to swap the wires.
mine actually ran but the timing was soooo far advanced it sounded really funny.
I wont get into the why but they need to be swapped.

I bought a new connector for my MSD and swapped the wires on the MSD side. I have a spare bosch unit I can drop in if the MSD goes bad.

get the MSD coil but mount it right side up.
it wil fit under the IC.
I had clewett make me a special coil wire with a 90 on the coil end and a little longer so it would fit.
if you get new wires from him have him put numbers on BOTH ends of the wires.
makes life a little better

[9dreizig]

It worked!!!!! Thanks again!!
I don't understand why but it did !!!

[timmy2]

What worked?
Swapping the green and purple wires?
If the above, It has to do with the rising impulse trigger of the distributor signal. Depends on clockwise and counter clockwise rotation for the correct trigger point.
The Porsche system is generally the reverse of the US systems.

[9dreizig]

Originally Posted by timmy2

What worked?
Swapping the green and purple wires?
If the above, It has to do with the rising impulse trigger of the distributor signal. Depends on clockwise and counter clockwise rotation for the correct trigger point.
The Porsche system is generally the reverse of the US systems.

Switching the green and purple wires...

[T77911S]

it has to do with the slope of the trigger out of the dist.
one side (the correct side) is very steep and stable, the other has a longer slope that actually moves as the rpms go up which advances the timing even more.

when you flip the wires it changes the correct slope from either pos to neg or neg to pos. the MSD triggers off the opposite one the bosch does.

I would have to go look again for exact details.

the signal looks kind of like AC in your house.