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Setting points gap using Dwell Meter

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Old 08-13-20, 03:18 AM
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Setting points gap using Dwell Meter

Hi, my apologies if this has already been covered elsewhere on the forum.....I searched but couldn’t find what I was after!

I have an early first gen RX7 12a NA with points ignition. I’m trying to set my points gap using a dwell meter however it only has options for 8 cylinder and 6 cylinder. There is a note stating that 4 cylinder vehicles can be set by doubling the value of an 8 cylinder. There is however no setting for a rotary!

So, does anyone know how to set the dwell with these limitations?

My thought is to double the 6 cylinder readings. This is based on 3 ignition cycles per coil per revolution, so essentially 6 per revolution but split between 2 ignition systems......so a “3 cylinder”.....I know......it’s a Taboo term!😀.
Old 08-13-20, 08:29 AM
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Waffles - hmmm good

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Use the 4 cylinder setting I think.God, I haven't used a dwell meter in years ( I mean like more than 20 ), not sure I remember how. Do us all a favor and write it up once you have it figured out. It would be useful for those early 79 owners out there.
Old 08-13-20, 08:39 AM
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use the 4 cylinder setting. the RPM part of the thing should agree, more or less with the tach in the car

Old 08-13-20, 08:44 AM
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Thanks to both.

Yeah I was overthinking it. At the end of the day the distributor shaft has 4 lobes, the dwell meter only reads how many degrees the lobes keep the points open for.
Old 08-13-20, 08:55 AM
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Originally Posted by Waytoomanycars
Thanks to both.

Yeah I was overthinking it. At the end of the day the distributor shaft has 4 lobes, the dwell meter only reads how many degrees the lobes keep the points open for.
i mean if you were going to ask what the dwell should be, i have no idea!
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