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Discussion Starter #1
Hi I have a 66 charger that idles perfect in park. When you put it in gear it pops and backfires but the timing appears to be OK I think. If I advance or retard the timing it just gets worse. any one have any good ideas...I will even take some bad ideas. :confused:
 

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Chris B,

How does it run once you get it rev'd up? Or does it take time to get it going?

Because you say it runs okay in park but backfires in gear, if I had to give an answer with no other info then I would say:

A. Bad spark plug wire
B. Too large a gap on the spark plugs
C. Flat cam lobe on an exhaust valve
D. Point gap too small

Just some thoughts
Scholman
 

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Discussion Starter #5
In park you open it wide up and it is all good. I have already done the cap, rotor, plugs and wires
 

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Chris B,

Could you have crossed a wire/ When there is "NO" load on an engine with a crossed wire they seem to run okay. When you rev them up they seem to run okay too. But when you put them under any kind of load the missing is very noticable.
I do not think it is a vacuum leak because then it would run rough but not pop and backfire, and if you were to advance the timing it would "ping" because the fuel and air mixture would be too lean.
I am still thinking it is a flat lobe on the cam....sorry.

Scholman
 

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Discussion Starter #8
OK guys thank you for the input. I already started thinking of crossed wires. I put them back the way they were when I drove it home. It was backfiring then too.So.... not to ask a stupid question but can anyone tell me the piston order on the block? I have never had to know that before. I already found the fire order.
 

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Chris B,

If the engine is a 273, 318,340,360 "A" engine the distributor rotates clockwise. The cylinders are the same as chevy small block that is even numbers on the passengers side and odd numbers on the drivers side.

On the "B/RB" engines that is the 361,383,400,413,426 wedge, 440 the cylinders are numbered the same way but the distributor turns counter clockwise

Have Fun
Scholman
 

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Technical Support Barry Grant
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Is it backfiring through the carburetor, or is it an after-fire out of the exhaust? The extra load of the torque converter can cause you to be lean, you may need to richen up the idle a little bit on your carburetor.
 

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backfiring.......timing or vac

older model mopars, like yours, had some trouble with the lifters bleeding down and not pumping back up, especially if you over rev the engine. This will appear to be a flat lobe on the cam, or timing chain jumped. before tearing into the engine, pour 1/2 quart of ATF thru the carb with the engine running at moderate speed. Pour slowly and do this outdoors as it will cause a lot of smoke. I have had to do this several times on my 1967 dodge 318, and it has worked every time...If your problem started "all at once" and you are the dark as to the cause, a couple of bucks for ATF is a cheap way to test .
 

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Race it, Don't rice it!
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How in the ### does ATF in the chamber fix a mechanical problem?


If your wires are good I blame a vacuum leak. But only if it goes away under part throttle application. By then you are in the transition circiut and the carb can cover it the lean spot.
 

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Discussion Starter #13
Once again I would like to thank all of you guys taking the time to respond to my 'typo' question. Last night I was thinking crossed plug wire and then Scholman said the same thing. I had the fire order and just had to figure out how the cylinders were numbered. The #5 and #7 wires were crossed. I feel bad everyone tried to help and it was just a stupid thing but THANKS :thumbup:
 
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