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Discussion Starter #1
After I changed my 2 1/4 inch dual exhaust for a 2 1/2 inch chambered setup, I made a comparison video. In the video ( have uploaded to MY Videos section ) you can gear a slight abng when I get on the gas at idle....I notcied it so stopped revving it...its at the 1 min 47 point...actually its hard to make out in the lo quality version...you can also see it here,
http://media.putfile.com/ComparisonMID

Anyway, didnt really think too much about it...
A friend has just fixed my WOT switch and so now I am out having fun with the hood induction system and the kickdown on the trans.

If I go from a stop and floor her, WOT, she picks up and then as the secondaries open and kick in, I get a similar sound coming from the exhaust...sounds like little back fires...only small...but enough to get me wondering what might be causing them/the noise.

The timing is set pretty good, Im getting full advance by about 2800rpm, 36 deg..The carb is a Qjet and is jetted as follows,

Primary jets: 75
Primary rods: 45
Secondary Rods: "DA"
Secondary Rod Height: 41/64"
Float Level: .375"
Idle mixture screws: 2-1/2 turns out
Secondary windup: 1/2 turn

Any ideas or am I being paranoid! :crazy:
 

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After I changed my 2 1/4 inch dual exhaust for a 2 1/2 inch chambered setup, I made a comparison video. In the video ( have uploaded to MY Videos section ) you can gear a slight abng when I get on the gas at idle....I notcied it so stopped revving it...its at the 1 min 47 point...actually its hard to make out in the lo quality version...you can also see it here,
http://media.putfile.com/ComparisonMID

Anyway, didnt really think too much about it...
A friend has just fixed my WOT switch and so now I am out having fun with the hood induction system and the kickdown on the trans.

If I go from a stop and floor her, WOT, she picks up and then as the secondaries open and kick in, I get a similar sound coming from the exhaust...sounds like little back fires...only small...but enough to get me wondering what might be causing them/the noise.

The timing is set pretty good, Im getting full advance by about 2800rpm, 36 deg..The carb is a Qjet and is jetted as follows,

Primary jets: 75
Primary rods: 45
Secondary Rods: "DA"
Secondary Rod Height: 41/64"
Float Level: .375"
Idle mixture screws: 2-1/2 turns out
Secondary windup: 1/2 turn

Any ideas or am I being paranoid! :crazy:[/QUOTE
Secondary windup should be 3/4 turn
 

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These settings are how Lars set the carb up......

So, you think it may be a carb issue or should I be looking at any thing else?
If Lars set it up, don't touch it. I would e-mail him about the 1/2 turn. I believe he uses 3/4 turn. He might also give you some insight as to your problem.
 

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WOT, she picks up and then as the secondaries open and kick in, I get a similar sound coming from the exhaust...sounds like little back fires.
is this possibly knock your hearing? not sure what your hearing but have heard others say that they thought knock sounded like small back fires.
 

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Discussion Starter #6
is this possibly knock your hearing? not sure what your hearing but have heard others say that they thought knock sounded like small back fires.
EEK!...I hope not.....

Have mailed lars. Will let you know what the guru says. :thumbsup:
 
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