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Diagnosing Exhaust Sound

Dan The Man

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69 Charger 440. Finally got the beast running, but I don't like the "motor boat" sound coming from the exhaust https://app.photobucket.com/u/stump...941f16/p/fdc4576c-e08d-4004-b8e4-7f9c90e01cf1. The entire exhaust is "new" as in never exposed to the elements and always garaged since installed new. The heat riser is just loosey goosey, but I have it tied off counter clockwise to always be open. I just starting using Rec 90 ethanol free gas. Still tuning the carb since I rebuilt it so haven't road tested yet. What do you think?
 
Sounds like a lot of misfiring to me.
What happens when you increase RPM??
 
Sound like the idle circuit in the carb is plugged up.

Idling to slow. To lean. Richen the mix.
 
Sound like the idle circuit in the carb is plugged up.

Idling to slow. To lean. Richen the mix.
OK changed out the plugs. Forgot what a PITA they are. Idle circuit plugged? I just rebuilt the card, so where should I be looking exactly?
 
What carburetor are you working with ?
 
Timing will do that. What's your initial set at?
 
Sounds fine - for a slant six!
No way that's hitting on all 8 right now.
 
Edelbrock 750 , your 2 air ,idle needles at the front take them out and spray some carb cleaner down each hole.
Screw them back in easy till the bottom out. Then back out 2 turns.
That should give you a good start point.
Like posted set timing 10 degree advance to start with.
Dbl. Ck plugs for fouling, plug wire condition and fire order like posted.
Bad distributor cap / rotor possible.
I've found cracked ( new ) plugs in the box before.
Just be methodical and test fire thr car after each change you make.
 
Edelbrock 750 , your 2 air ,idle needles at the front take them out and spray some carb cleaner down each hole.
Screw them back in easy till the bottom out. Then back out 2 turns.
That should give you a good start point.
Like posted set timing 10 degree advance to start with.
Dbl. Ck plugs for fouling, plug wire condition and fire order like posted.
Bad distributor cap / rotor possible.
I've found cracked ( new ) plugs in the box before.
Just be methodical and test fire thr car after each change you make.

OK Cleaned the air/fuel mixture screw holes and adjusted as stated. Ckd timing and it was already at 10. Plugs and wires are new. Cap and rotor fine. I even adjusted the air gap between the reluctor and the pu. It was more than 008. Starts right up. Idles ok but when I gas it from the carb, I get a back fire. Coil?? I've mentioned several times that I now use Rec 90 ethanol free gas for the first time ever. Could this be my friggin problem? It's very frustrating because this car ran awesome before it sat for 5 years. Although garaged and never exposed to the elements.
 
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