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Old 05-01-2024, 09:54 PM
70GS455 70GS455 is offline
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Join Date: Oct 2002
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Quote:
Originally Posted by grd777 View Post
have the same issue with my tach let me know how you make out
If it's the MSD 6AL box and your using the dedicated grey tach wire, the issue could be the tach. That signal is a 20% duty cycle square wave, which means it's 80% dwell, or 36 deg dwell. The factory tach will have trouble with 80% dwell as the rpms climb. There are those of us that have modern circuitry available that handle large variations in dwell very well.