[Schurkey]

Originally Posted by TransAm525

Is that supercoil for reverse rotation distributors, or is it some universal Chevy item? The coil must be matched to the specific direction the distributor rotates. The pickup coil is matched to the coil and the rotation of the distributor. If you are running a clockwise rotation coil in a counterclockwise rotation distributor, the timing will be off and the polarity will be reversed, causing all sorts of timing issues. The fix is either to install the correct coil (with the correct white or yellow lead wire from the coil) or to swap the pickup coil to match the coil being used. Red/yellow coils go with yellow connector plug pickup coils. Red/white coils go with clear connector pickup coils.

I too ran into the same situation. I am running a 71,000 volt Petronix race only coil, but they only make them for clockwise rotation distributors. My fix was to swap the pickup coil to a clockwise rotation pickup. As long as the two match, the polarity will be correct.

Distributor rotation has NOTHING to do with the color codes.

The main problem seems to be when the car is cranking. electro-magnetic interference from the starter can cause misfiring if you have the "wrong" coils. The black and clear/no-code pickup coils are identical except for the longer leads on the clear/no-code pickup coil. They are wound "backwards" from the yellow coded pickup coil. Since there are two ways to wind the wires on the pickup coils--clockwise and counter clockwise--there are two igniton coils to match them. Again, this is not the direction the distributor spins, it's the direction the wires in the pickup and ignition coils are wound.

Chevy, Cadillac, and Olds Toronado use the yellow coded pickup coil and the red/yellow ignition coil.

Buick and Olds except Toronado use the black coded pickup coil, and the red/white ignition coil.

Pontiac uses the clear/no-code pickup coil, and the red/white ignition coil.

Note that the Olds engines uses either coil set, depending on whether it's in a rwd or fwd car. The distributor rotation does not change. The FWD Toronado has the starter motor on the opposite side of the engine for transmission clearance.

You can verify this from Delco service information at:

http://fiedlerh.home.att.net/HEI.pdf

[TransAm525]

Here we go again...

Yes, it does matter. I do agree with the location of the starter cable, but the polarity is also different. The engine will start, and in most cases run fine, but the timing will change and the user may experience backfiring and eratic timing. Below is a picture of what the signal looks like when the coil fires. When the coil is mismatched, the signal is reversed. Do a search in the forum and you will see a 5 page discussion on this topic. One of the electrical engineers on this forum performed his very own test and found the same results I speak of.