PerTronix / Relay issue at low RPM

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Joined
Nov 8, 2010
Messages
119
Reaction score
1
Location
Choctaw, Oklahoma
My Car
1973 Mach 1
351c 2v
Edelbrock 4bbl, Performer Intake
Ram-Air
Pertronix Electronic Ignition
Hey all,

I just installed the replacement starter relay offered by PerTronix. I have the Ignitor III and their Flamethrower Coil as well. The latter items have worked ok but it was noticeable that I wasnt using un-resisted DC for the unit. So yesterday I installed the replacement relay.

WOW what a difference. The car starts right up and runs as smooth as can be... until you pull out of the driveway. Under moderate to high acceleration no issues noticed, but at low acceleration between ~1300 and ~1600 RPM the tach bounces between 0 and 1500 or so. The engine is off then its on then it off then its on if you know what I mean.

Could this be timing? I understand that when you mess with the PerTronix that you should check the timing but I can't get it straight in my head. I guess my first point is to check the timing but Im still lost as to how it could be a problem.

Thanks for any insight you can offer.

 
I don't think it is timing. I would check how you have it all wired up. The tach is part of the entire system (unlike a lot of other cars). If it is dropping to zero my guess is you are not getting a spark. Weird symptoms though...

 
I don't think it is timing. I would check how you have it all wired up. The tach is part of the entire system (unlike a lot of other cars). If it is dropping to zero my guess is you are not getting a spark. Weird symptoms though...
Oh I know Im not getting a spark. Its a complete misfire seemingly every other spark. And If it were wiring then why only in such a small RPM range when all the other driving is great?

 
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