rough running....backfiring 350

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legopnuematic

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#1 on a Chebby is drivers side front.

What you have labeled as #6 should be your #1, going clockwise from there 18436572.
 
Sad Sack

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Ken B said:
Please allow me stupid questions....I just dont know but really want to figure this out.
Why would this vacuum line be plugged?
Shouldnt that have vacuum hose to the front of the carb???

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We use to cap that off when installing a distributor curve kit in them.
 
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Ricko1966

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Ken B said:
Please allow me stupid questions....I just dont know but really want to figure this out.
Why would this vacuum line be plugged?
Shouldnt that have vacuum hose to the front of the carb???

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That should have a hose going to a manifold vacuum source. There will be arguments to follow some are going to say it goes to ported. Ported is an emissions crutch to light the fire later at idle reducing CO at idle.
 
Ken B

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I want to say thanks again...running in and out from garage and reading and trying to take pics to show what I see.....hard to translate sometimes
 
Ken B

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Distributor labeled correctly now?
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Ken B

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passenger side wires labeled correctly?
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Ken B

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drivers side labeled correctly?
 

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Ken B

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Rikko,
If you can see that vacumn line I USED to have....thats where is should land on the carb from the distributor correct?
vacuum hose has blue painters tape on it
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Ken B

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I am thinking the same thing. but you guys on here know more than i do. I was told to check firing order...so I am just trying to confirm that its all correct. I will label stuff more permanently later.
Just trying to figure out the misfire and learn WHY....
 
Ken B

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this engine will run fine in park and when you rev it up but when you start driving is when I have the backfire/misfire crappy stuff happening.
 
Terlingueno

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I hold to my original post, I think you should put the vacuum hose back in place and fire it up...then drive it and see if it still manifests the issue.
 
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legopnuematic said:
#1 on a Chebby is drivers side front.

What you have labeled as #6 should be your #1, going clockwise from there 18436572.
Click to expand...
He's got drivers side and passenger side flipped.Ill see if I can him a pic. Brb
 

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Ken B

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I want to learn this stuff.
I saw that vacuum line off the distributer and it seemed wrong to me but I am inexperienced
heading to get some 5/32 vacuum tubing and we will see.....
 
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