I bought a new cap, coil, rotor and module today. The coil diagram shows a secondary ground wire running from the coil screw to the middle terminal on the plug, and a peice that goes under the coil, along with a warning about not using the secondary ground. This wasn't in place on my old coil, which led me to believe thats why I fried it. I had fire but not for long. How do I know if this is necessary or not? As i understand it some used it and some didn't. I don't have the metal peice that runs under the coil, And I'm still not getting spark.
I'm certainly not an HEI guru. I have put three HEIs in my 455 (two original GM units and one aftermarket) and one in a GMC van with a Chevy 350...but that's it. What I am curious about is the piece under the coil. Every one I've looked at has an insulator, and the (god bless me but I'm drawing a blank on this part's name) a part that looks like (somebody help me with the name, this is driving me nuts) a short rod with a rounded tip attached to a short spring. This goes through the cap onto the rotor. And that's it. What is the piece under the coil that you don't have? I've never seen anything but these two parts under the coil.
It a funky little peice of metal strap that runs from under 1 of the coil mounting bolts on the bottom side of the coil to the peice you are talking about. Does yours have a ground wire running to the center terminal on the plug in? The diagram on the new coil has a pic of it, but I don't have a scanner. Here's some info I got off the BPC email list: "Some coils have three wires. Two that go to the plug, usually yellow and red. the third is a ground that goes on one of the four bolts that hold the coil to the cap. I do not know why they all do not have the ground wire. With out the metal piece that goes to the center of the plug you will not have a ground. It will run with out it, but not for long. Make sure you have a ground in the cap. It's a funky looking metal thing that sits under the coil I know NAPA sells them. They get left behind when people change the cap." Needless to say NAPA or anyone else didn't have them but knew what I was taliking about.
I have the ground going from one of the bolts that holds in the coil (upper left as you look at the coil from the front of the car), to the center terminal connector for the module, the blade for the ground fits between the other pair on the coil in the cap. On my old ones, this was an actual wire; on the new one I have, and on the last coil coil I bought, I have had a formed mtal strip that replaces this wire (I assume they had an issue with the wire getting pinched under the dust cover), but this grounding "strap" must sit on top of the coil in my HEI, or it will not fit into the slot in the cap for the terminal. If it were to go under, the blade of the connector would point up and not down. I've never seen the type you describe, or else I am misunderstanding. I had a Firebird with HEI that used the red and yellow wires, the ones for my Buick have all been red and black with a seperate black ground, or this formed metal ground strap.
I'm trying to get that info clarified. I'm thinking the person was describing the same thing you are. Confusion is setting in. In the mean time I'll have to get my module and coil checked out, and step away from it for a week. Thanks for the input.
Well, if this becomes a hopeless mess, I have an HEI with so-so bushings that worked when I yanked it out. If you like, you can have it, it's just collecting dust in my shop. It's not an all-star part but if you need another one it's yours.
I sent this one to JW to set up so I'm sure there's nothing wrong with it, other than the parts I've put on it. Thanks for the offer though.
