Author Topic: 440 six, Still having misfiring problems  (Read 2954 times)

Offline Blackcuda

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440 six, Still having misfiring problems
« on: August 21, 2006 - 08:11:36 AM »
My 440 six-pack is still misfiring, I swaped out a very low battery and put in a red top. The car runs a little better, but at higher rpm it still misfires. Could this be a bad alternator, or moisture under the distributor cap? It has been very humid here in south florida.




Offline MEK-Dangerfield

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Re: 440 six, Still having misfiring problems
« Reply #1 on: August 21, 2006 - 02:30:05 PM »
I re-read your first post about this situation. Would you describe this as a back-fire, or a miss in the engine? I'm still thinking it's in your electrical system, but I had a coil once that would go crazy once I hit 1700 RPH.  :22yikes:

  Mike

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Offline Chryco Psycho

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Re: 440 six, Still having misfiring problems
« Reply #2 on: August 22, 2006 - 12:04:49 AM »
it could be moisture , WD40 will fix it , it could be a weak coil , bad wires , could be tuning in the 6 pack too start checking stuff , I need more clues 

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Offline Blackcuda

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Re: 440 six, Still having misfiring problems
« Reply #3 on: August 22, 2006 - 07:25:15 AM »
I'm in a bit of a problem, I know no one who knows how to tune a six- pack car properly. As far as changing plugs and wires and general tinkering I can manage.
The car starts up and idels fine, once I get the rpms up it will misfire and sometimes a small backfire.  The last time I looked at one of the plugs it was dark black, so I took the car out for an "Italian tune up". Which means getting the car out on an open road and running it hard to blow it out. This worked really good, and the car ran much better.
I'm going to start with the distributor, and then go from there. I know my 440 has some big power lerking, but I can't seem to get out.

Offline pandamarie

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Re: 440 six, Still having misfiring problems
« Reply #4 on: August 22, 2006 - 08:57:36 AM »
after you check your wires plugs and coil to make sure everything is ok check the springs on the two outer vacuum pods, you might have to put heavier springs in them if your plugs are running black, I have the heavy black springs in mine since I use it for a daily driver but run the yellow spring in the front and the purple in the back so they are slightly staged. also check your float level on all three carbs, helps if you have an electric fuel pump, I have had to replace all the float bowls on my carbs due to old age, holley also makes a better needle seat assembly that will give you more adjustment, sorry I dont have the # for them.
 Also check to make sure your mechanical advance is working and your vacuum advance is not leaking, I had those problems also.
1938 packard 120
1948 lincoln convertible coupe(1 of 16)
69 charger
70 challenger R/T 440 6 pac
71 challenger 340 R/T 4 speed
2-1961 nash metropolitans
forgive wifes 75 vette
2002 dakota 4.7

Offline Challenger6pak

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Re: 440 six, Still having misfiring problems
« Reply #5 on: August 22, 2006 - 09:36:43 AM »
Send me a PM with your ph. #.  I am in S. FL.  also.
1969 Sport Satellite H code convertible, 1970 Cuda 440+6, 1970 Challenger R/T 440+6, 1970 Challenger 383 R/T auto, 1970 Challenger R/T 383 4 speed,1971 Challenger convertible.

Offline Chryco Psycho

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Re: 440 six, Still having misfiring problems
« Reply #6 on: August 22, 2006 - 12:39:55 PM »
worst case I could fly down & set up the 6 pack , I have only done 20+ systems & April is a good reference too

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Offline Blackcuda

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Re: 440 six, Still having misfiring problems
« Reply #7 on: August 22, 2006 - 01:14:12 PM »
Are you planning a trip to South Florida?

Offline Chryco Psycho

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Re: 440 six, Still having misfiring problems
« Reply #8 on: August 22, 2006 - 02:11:26 PM »
I was just in Ga which was not too far away to make it work , too bad I didn`t know about it then but I have no plans but could arrange something if needed

Challenger - You`ll wish You Hadn`t

Offline Blackcuda

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Re: 440 six, Still having misfiring problems
« Reply #9 on: August 22, 2006 - 02:51:36 PM »
I was just in Ga which was not too far away to make it work , too bad I didn`t know about it then but I have no plans but could arrange something if needed
I'll send you a PM.