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Discussion Starter #1 (Edited)
Maybe i made big goof this weekend. Very frustrated and no mechanical genius here.

Situation - 67 cutlass runs great but misses a little at high RPM at WOT. Not fuel delivery related. Have Pertonix not points.

Replaced worn out wires, cap - performance got better -
but not totally solve misses.

Thought maybe good to replace ignition coil and rotor. Got Pertronix Flamethrower II coil and rotor installed.

Car starts real rough and then dies - hasnt started since.

Maybe it all fell apart when no read instructions.
Thought install coil was plug and play. I then read instructions and it say Flamerthrower II not to be used with regular Pertronix Ignitor system. I then put back in old coil and rotor still no start.

Two questions:
1. Could that coil have fried the Pertonix ignitor system?
2. I didnt install the pertronix system , but read on a web site Qouting here ----"The required gap between the module and magnet ring is set with the distributor installed in the engine. "
Could I have goofed the gap when changing cap?
Am I reading that right? If so, how to set?
That is why I try to find instructions for install.

Thanks.
 

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2,625 Posts
That sounds like the early model Pertronix I had on my '67, i.e. the magnet ring which rotates above the main unit mounted on the breaker plate.

My instructions said the gap between the ring and the unit should be no less than .010 and no more than .040 (If I remember correctly). If the gap is more than .100 installed, the engine will miss or not fire at all.

Prior to installing the unit, did you check for excess gap at the gear end of the shaft? The kit should have included some shims to eliminate that gap. Add the washers to get the up-down shaft movement down to about .020.

To test the unit:
1. Remove the coil wire from the distributor and ground it to the engine.
2. With a multimeter set to 50 volts DC, put the red probe on the negative coil terminal and the black probe to ground.
3. Have someone crank the engine.
4. If the meter shows:
A constant reading of between 1 and 3 volts, the Pertronix unit is bad.
A fluctuation of between 1.5 and 12 volts, the unit is ok.

Hope this helps.
 

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Discussion Starter #3
thansk for reply -
actually i didnt install the ptronix and the unit has been working for about 12 months (very little usage).

when i changed rotor could i have goofed up this gap between the ptronix unit and ring? or once you get that gap set , does is stay same always?
 

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Well, the rotor does mount on the studs that come up from the magnet ring. I guess something could have moved. Can you see if there is a big gap when it turns over?

I would also try the test to see if the unit is bad.

I pulled my unit because the gap closed up when it got hot...unbelieveable backfires!

I've got the newer model (1181LSC) that doesn't have the magnetic ring, but I haven't put it in yet. I'm running a temporary points distributor in the interim.
 
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