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MSD ingnition problems

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Old Apr 14, 2010 | 12:13 AM
  #16  
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sean78SC
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From: Rutland, Vermont
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Thanks for the advise. I got the idea from Waynes book, 101 projects for the 911. The goal was not so much a performance increase, but to improve drivability and fuel economy. The article states a performance increase under 3,000 RPM due to more sparks per turn. I am planning on other mods in the future, and wanted to make sure the ignition system was top shelf. We have contacted MSD directly to see if they can help sort out the problem. Will keep everyone updated.
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Old Apr 14, 2010 | 01:54 AM
  #17  
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Lorenfb
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From: SoCal
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"The article states a performance increase under 3,000 RPM due to more sparks per turn."

Total hyperbole as other issues/info in that book! A lot of the info is 'hearsay'.
Not a book on the reading list at the Porsche factory.

The key factors for spark ignition are:

1. a minimum spark energy
2. a minimum spark voltage
3. a minimum spark duration

The number of sparks, as per the MSD, is of NO value, i.e. by the time the next MSD spark
occurs, 1. the combustion process is fully underway, 2. the piston has moved such that
no additional ignition contributes to further energy release from the initial fuel charge.

Bottom line: If the MSD technology had any real merit, any OEM (Porsche, BMW, GM, etc)
would buy the technology or license the patent if one existed and utilize any benefits
of the technology to enhance performance or reduce emissions.
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Old Apr 14, 2010 | 05:01 AM
  #18  
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From: Orem, Utah
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I did the MSD Ignition on my 80SC last year. I had the exact same problems you are mentioning. I did the conversion myself following the instructions exactly and calling MSD on several occasions to discuss it with them. Then I took my car to a mechanic who reviewed everything and changed nothing.

In the end I took the MSD out and returned it for a full refund.

Car runs great on original equipment.

Rob
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