I just finished installing my MSD system consisting of :
MSD 8350 Ready to Run Billet Distributor
8910 Tach Adapter
MSD 2 Coil
MSD 6AL ignition box
Thought I'd share an interesting story with you.
I initially got the system installed rather easily. The car started on the first try and ran like a champ. The only thing wrong was that the tach was dead. BTW, the instructions that came with the distributor does not address connecting it to a 6AL ignition box. I rechecked the wiring and connections and not achieving success, I decided to call MSD tech support. The guy who answered acted like I had woken him from his nap and couldn't care less about my problem. After a few questions, he told me that since I was running a ready to run distributor, I needed to run the 8910 tach adapter instead of the 8920.
I went out and luckily found the 8910 at a local parts store. I installed it as detailed in the diagram but since none of the instructions addressed installing with a ready to run distrubuto set up, I again called MSD tech support. The second tech was a bit friendlier and gave me the wiring instructions which I wrote down step by step as he gave them. After hanging up with him, I set out rewiring the setup. As I looked over the diagram that he had given me the wiring didn't seem to make sense. This looked too wrong and I decided to call back and confirm.
A third tech answered the phone and confirmed that the connections were not correct. We went through rewiring 3 times and the car now wouldn't start unless the tach adapter was removed. He made the comment "you're only using it to drive the tach? Then you could have used the 8920" Am I missing something here or is the purpose of the tach adapter to drive the tach? Is there another feature that it does? The tech told me that the adapter was defective and to return it. I returned it and luckily the store had another one. I hooked it up per the instructions that tech 3 had given me and the car still wouldn't start. Did I mention that none of the techs had foreign accents so I don't believe that I was getting off shore tech support. Maybe it was some kid getting paid minimum wage for after school employment?
Following my better instincts, I didn't call MSD technical support again! Using the product included instructions, instructions received from SoBill (thanks SoBill) and a volt meter, I finally figured out the problem. The 8910 adapter comes with a diode that is placed between the white wire of the 6AL and the tach adapter. It is installed using pre installed male/female spade connectors. Well the Mexican, Chinese, Taiwanese or wherever factory that this was manufactured put the diode in backwards! Not to mention that the diode is heat shrinked so that you cannot see its orientation. I changed the connectors to flip the diode around and everything now works as it should.
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