Plugs #1,3 and 2,4 fouling

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bigdemo1

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Got something funny going on plugs from cyls #1,3,2,4 are fouling and rest look good,360 edelbrock 750,edelbrock performer rpm intake,re-curved dist,blaster 2 coil (with msd ballast as per their instructions)accel wires,I am thinking that the air cleaner is not allowing enough air,I have my choke hooked to 12 volt wire(on the ballast)could my choke be closing?this is the second time for this,I've changed the cap and button also wired the second opening on the breather open(dual snorkel)thanks.
 
Soot fouled real black,others look perfect.
 
Sorry should of mentioned hedders,but I did give my mufflers some thought.
 
Went through the carb lift and drop settings corrected,also have a regulater and guage set to 5psi.
 
Man, it sure sounds like a choke/dribble issue.......... I wonder if the EB carb has a flaw somewhere..........

What kind of driving are you doing? And does it channge with HWY/CITY driving?

Do they all get black when idling?

What cam you running?
 
dodgetkboy love your engine pics,I'm leaning towards restrictive breather/choke,carb looked to be fine,I use it as a daily driver year round(northern Alberta)combined driving,was a 508 purple,changed to a stock 340 lift purple(truck weighs 4200lbs and I got tired of revving the crap out of it)this has happened twice in last couple months,I've changed gas stations and same thing.
 
Hmmmm, happened twice, buit not all the time................

If it isn't constant, I am still thinking float issues........ Jest because I have had trouble EB's in the past..... Are the floats hitting the sides of the carb body? Seats and needles free and tight?

IDK

Thats a strange one....

You like my before and after pics eh? thats a 318 to a small port head 390, thing pulls like a SOBeeatch@!
 
I would unhook the choke wires and wire the choke open and see if it's the choke.
If this does not fix it ,then i would lean the primary fuel ratio on the carb.
It's the carb ,but what part of the carb is the question.
I had a electric choke on a holley carb before and i hated it.
The choke just seemed to darken the plugs to much all the time no matter what i did.
I don't run a choke on any of my cars anymore, because when the carb is set up right,you don't really need one.
 
I would unhook the choke wires and wire the choke open and see if it's the choke.
If this does not fix it ,then i would lean the primary fuel ratio on the carb.
It's the carb ,but what part of the carb is the question.
I had a electric choke on a holley carb before and i hated it.
The choke just seemed to darken the plugs to much all the time no matter what i did.
I don't run a choke on any of my cars anymore, because when the carb is set up right,you don't really need one.
It,s cold outside already here in Canada,choke is a neccessitiy.
 
T67, just thinking out loud for a sec.........

If the mains were too rich, wouldn't ALL the plugs be fouling?

I almost wonder if it is a vac leak, maybe in the back of the manifold, AND the carb is too rich?????

Usually, #5, and #7 run the richest with that manifold.........
 
Quote: almost wonder if it is a vac leak, maybe in the back of the manifold, AND the carb is too rich?????



I was kind of thinking the same thing, what's your manifold vacuum at idle. Then plug off the PCV line and check again.
 
You know I honestly can't remember the vacuum reading as I set the timing with vac guage something tells me it was around 17 or so(corrected for alt@1000ft)there are no vacuum leaks,I've been leaning towards the choke power wire and will probably take the top off carb again for another look,this edelbrock has fought me all the way from new,but I wasn't going to put the holley on until spring.
 
I just can't figure out why the plugs from the front of the motor foul and the back stay so nice,maybe it's dribbling fuel,but why only the front?
 
kimmer,changed out button cap and wires,no signs of arcing on cap and button looked normal,when I set the reluctor gap it showed that some of the ribs were(or seemed)to be closer than others,so I gapped to what seemed like the longest one(reluctor worked okay before)
 
anybody gonna mention changing the metering rods??? primarys are on the front two bbl's secondaries dont have metering rod's kinda stands to reason the primaries are closest to the cylinders that are running rich,eddies are not really an out of the box carb, then again no carburetor can go without adjustments and calibration unless yur just a lucky dawg.....JMO
 
WagginI thought about this but it didn't make sense as cruise circuit is all same step of rods for all cylinders.
 
I would look into the ignition a little deeper. Pull off each wire and use a test plug to check the spark.
 
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