I purchased the Atomic TBI unit about two years ago for installation on my Chevy 348 engine (early W motor). Installation went fine motor ran good. I decided to go to the next step, using the timing control available with the Atomic system, the instruction manual indicated I should use their 'Ready to Run' distributor # 8393. I also purchased the recommended coil and the adjustable rotor. The instruction book for the Atomic shows how to wire the distributor on page 10, but this did not wire it for the timing control feature I wanted. There are no instructions in the Atomic installation book on how to do this. There are instructions on page 18 but this is for a distributor with 2 wires, not 4 that the ready to run has. Some how 2 years ago I figured out how to wire up the distributor so the timing control would work, weather the tech line told me or I figured it out I don't remember, but it worked for about 1000 miles.
Recently I been having timing issues creep in, poor acceleration, back fire through the TB, ect. I started to check out the distributor and timing control. Checking voltages I found 12v going to the distributor, I also checked the wires coming from the Atomic TB that are used on page 18 of the instructions for the distributor, which at this time were not connected, they have just under 5v. Since I have no wiring diagram to reference in the Atomic book for my ready to run distributor with timing control I became concerned that I had supplied too much voltage to the distributor with the 12v I had connected at the time. I also have a MSD 6A ignition box connected which also has a connection for the 'mag' distributor. It also has the 5v on it.
Looking at the ready to run distributor all you see is the mag pickup, the circuit board is under the plate which I was not aware of at the time. I checked for resistance on the mag pickup and found it to be open! How could that be? The engine should not run with an open on the pickup, resistance should have been 500 - 700 ohms per MSD web site. I ordered a new pick-up. upon receiving it I disassembled the distributor to replace it, what do I find, the circuit board under the plate!
Scratching my head I call the tech line, waited 15 minutes on hold, then was connected. First tech guy I talked to lasted 15 seconds, got frustrated with my 5v questions about the Atomic wires suggesting that they do not have 5v, he put me on hold and passed me to another tech. This guy had a little more patience, but not much. I fully explained to him my set-up but as soon as I mentioned the 5v things changed. The one thing he did mention was that MSD does not make a mag distributor for my engine. I still had not made the connection about this 5v wiring for timing control. We ended the conversation with him fully believing I had no business wiring anything on my car as I had no idea what I was doing. Needless to say I was not happy.
Going over the parts spread out on my work bench, looking at the wiring diagrams, finally the light bulb went off!!! The ready to run distributor has the mag pickup which uses 5v but this needs to be amplified so the coil can use it for making spark, which is why you have the circuit board under the plate and that uses 12v. Hence the Ready to Run part! Now if you have a distributor with JUST the mag pick-up you use the 5v wiring from the Atomic OR the 6A box the amplified circuit is being done in either of those devices.
Please correct me where I am wrong about this. Anyway, why are there no wiring diagrams in the Atomic instructions for the ready to run distributor using the timing control? Why are the tech people so resistant to any mention of 5v from any wires? Why have I spent almost $1500 on MSD components and having any problems at all?
I have since removed the ready to run distributor, installed a stock distributor with mechanical and vacuum advance which I spent over an hour setting up on my SUN distributor machine to the exact advance curve I want. I also am using pertronics trigger to replace the points. I have also modified the ready to run distributor to be used as a mag pick-up only so it can be wired per the diagram on page 18 of the Atomic instructions. If I ever feel the need to try it in the future I feel confident it would work using the timing control. But if my present install works, why bother?
In the future I will seek out other manufacturers products for my ignition needs as I have lost my desire to spend my money on a company that has tech people with no patience with paying customers trying to wrap their heads around instructions that are in-complete. I may not be as smart as your tech people, but the reason they are there as far as I am concerned is to listen to my problems and try to understand what it is I am trying to do. If I am wrong, don't treat me like an idiot, that is not your job. Plenty of other people are around to do that.