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Old 01-07-2006, 09:11 AM
onovakind67 onovakind67 is offline
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A typical tachometer that hooks to the ignition system isn't reading distributor rpm, it's reading pulses per unit of time. A tach set up for 6-cylinder engine will read 33% high if you hook it to an 8-cylinder engine. If your V-8 engine is misfiring and the pulses aren't getting to the tach, the rpm reading will be off. The numbers you read are only printed on the face of the meter, so you can adjust them to represent anything you want.
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