Topic: Spark plug wire order
in Forum: C3 Engines
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Good Afternoon,
I had a wild hair this past weekend and changed out the spark plugs on my 72 just because. 350 engine, 4 speed. After I finished I was excited to start the engine, because I thought I had done a good job. Well much to my surprise it didn't run good at all, spitting and spuddering. I think I might have crossed a wire or two and I seem to remember some time back someone had the order the wires are run. I'd appreciate any information on how they should be run. Thank you.
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Firing order is 1 8 4 3 6 5 7 2
From the top looking down distributor turns clockwise. #1 is in front slightly to the driver side, depending on timing adjustment.
Driver side front to rear 1 3 5 7
Pass side front to rear 2 4 6 8
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Thank you Kstyer and Adam. I really appreciate the replies. I'll have to wait until this weekend to check the order. I thought I kept track of how I pulled them off, if anything I might have crossed 2 & 4. Thanks again.
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In my business (AC Contractor) I take pictures of all components and wiring before I rip it apart. Much like Autos, Bubba gets in there and will use whatever they have to fix a problem like green wire on all low voltage. So to save time i can review the pic and not have to ring out the wires.
Just a tip!
My #1 is not in the standard spot, it's one off. Put your timing mark on TDC and the rotor will be pointing at either #1 or 180 degrees from it. That's your starting point.
|UPDATED|8/26/2015 9:45:52 AM (AZT)|/UPDATED|
|UPDATED|8/26/2015 9:45:52 AM (AZT)|/UPDATED|
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+1 on Gary's comment, make sure you are at No. 1 TDC on the compression stroke before removing or installing any wires.
Not to create any confusion but I believe the distributor placement shown in Joel's diagram is for a later car with HEI ignition, '75 to '82. The rotation and firing order are correct, but I believe the #1 plug position on your car is as shown on the diagram attached.
These are the instructions I received with my new plug wires from Bair's. Note how the number one plug wire position is at the passenger side front of the cap, not the drivers side front as shown in the previous diagram. The is the way my '73 (non HEI) was and I believe what Gary was referring to when he said his was one off the position shown in the first diagram.
Not really sure why GM made this change but a few months after doing my '73 I did plug wires on a '75 HEI car and this difference stuck in my head.
In any event make sure your distributor is at #1 TDC. If you rotated to TDC on the balancer and timing mark you are at either #1 compression or #1 exhaust, you want to be on #1 compression. If your rotor is pointing anyway towards the rear or firewall of the car, chances are your on an exhaust stroke. Give the motor one more full turn to TDC again and note the position your rotor is pointing towards the front. If it's drivers side front, use Joel's diagram, if passenger side front use the one I have attached.
Good luck and let us know how it turns out.
John Sigmund
valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member
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in Forum: C3 Engines
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