600 edelbrock secondary bog.

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dieselman966

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So I found out earlier this week that I only had 3/4 throttle with the pedal to the floor. I bought the bracket to fix that and now have wot. But now my 360 bogs when you floor it. Can't seem to figure it out. The motor is stock with edelbrock air gap intake and a skip white hei distributor. Runs great with the secondaries disconnected. What will get rid of that big at wot? I have tried the %8 richer secondary jets. That didn't seem to help though.
 
when you look down the primaries, and work the accelerator linkage with your hand (engine off), but already warmed up, do you see instantaneous, strong squirt of fuel?
Is it a new, virgin Edelbrock or is it used. Sometimes the accelerator pump cup seal is not sealing to the pump "well" well. There is also at least one, maybe two check balls in the accelerator circuit. Look at a rebuild kit exploded view, and assembly notes for location and size of ball(s). There might be a brass check "rod w/tapered end" under the accelerator squirter cover. Sorry, I haven't worked on one for like 25yrs, and I've slept since then, so memory is a little fuzzy.
Make real sure the float level is correct. Hope this helps.
 
Try moving the bracket rod to the hole closer to the carb body. This will give more squirt. Should help, at least a little. -- Be careful, not to loose the little clip.
Edelbrock - Accelerator Pump Bracket.JPG
 
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I bought the carb used. But its supposedly new and I have checked the float levels twice. They are spot on. Just tweaked the hanging measurement a hair. The accelerator pump works good. Strong squirt when you move the throttle. I unhooked the secondaries last night to see if the primaries worked good and it ran great then. No flat spot or hesitation at all. It's just the when the secondary circuit opens up. I have played with the metering rods a little bit but I thought that they are just for the controlling the main circuit not the secondaries.
 
I have the orange in it now. There was silver before. At wot I have 4# of vacuum. I even tried the blue springs to see it it would help. Do the metering rods have anything to do with the secondary circuit?
 
Just thinking out loud here. Is it a pretty hot 360 or closer to stock?
 
The orange spring is what the carb comes with from the factory. With my experience, the orange spring works best. I have run a 600 ede on my 360, and love the carb. I finally settled on the 650 ede.

Having said that, I would take the carb off and blow out all the circuits with compressed air.
Then I would check jets,rods, springs, and put the carb back to box stock if isn't already.
At least you will know exactly what you are working with. Recheck the floats. Put it back on, and try it.
Make sure the choke opens all the way. Make sure you adjust the a/f correctly.

On another note....Whats your timming set at ?
 
I can clean it out. Can't hurt. So far the only thing I have changed on the carb is the idle mixture screws. I did that after I set my timing. I have that set at *15. Total of *34 with the mechanical. Vacuum brings it up to *53. I changed the secondary jets last night but it didn't get any better.
 
what is vacuum @ idle? @ what idle speed? where is vacuum taken for vacuum advance? where is vacuum gauge sampling @ idle?
 
is this a automatic ,could be kickdown out of adjustment ,not down shifting ,does it bog down when you manually shift it?
 
Edelbrocks are copies of the old Carters. I don't think you mentioned if yours is the AFB or AVS style.
Out of the box settings are pretty good for a starting point. You might consider going back to them and tune from there. One thing at a time. Edelbrock used to have their carb manuals available online.
Sounds like you are getting a BIG gulp of air without an appropriate amount of fuel. Accelerator pump needs to be good. Rate of secondary opening is easier to adjust in the AVS style.
 
Vacuum at idle is 22" it's around 25" at cruise. Vacuum reading is at the brake booster. And the vacuum advance is pulled off of the manifold vacuum port.

Is there an accelerator pump for the secondary side? I thought there was a booster that helped get it going back there until there was enough signal for it. This is the 600cfm afb style carb.

The car is an automatic. Kickdown is adjusted properly. It still bogs even when shifting manually.
 
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no accelerator pump for secondaries. the sec air is controlled by an opening brake: be it a weighted air valve, torsion spring-loaded air valve, and/or even the choke pull off in some cases. Basically it slows the sec opening until it's theoretically ready for the huge rush of air coming
 
Being that it's used, has someone removed the air door butterfly on the secondary side?
 
No the air door is there still. Does the primary side come into play with this? Because if I disconnect the secondary side it runs great.
 
dieselman966 said:
To small of a carb then?
Click to expand...
No and yes but just a tuning change, not an excuse to run out for an 850 yet,lol.
As KosmicKuda said, your engine is getting a big gulp of air without an appropriate amount of fuel in it.
That carb is an AFB type, so the weighted valve out back is gonna need to be slowed down a tad,or the metering rods lifted faster/higher, or the pumpshot retimed to cover the lean-hole, or the boosters removed and cleaned,together with their fuel and air passages,jets, bleeds and emulsion tubes , or the float level SPECIFICATION you are setting to, verified; or some combination of those, or all of those! lol.
Moving the linkrod up or down the arm, requires the linkrod to be bent to reposition the capacity of the stroke. And the S-link orientation proven.

PS, I'm trying to remember if the secondary side has an advance fuel delivery system, like a transfer slot, but I'm drawing a blank. I think there isn't.
EDIT:Yeah there is. It's operation is shown on page 4 of the owners manual. I think yours is defective or dirty
www.edelbrock.com/automotive/misc/tech-center/carb-faq.shtml
 
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What do I need to tune? I have not messed with carburetor much. I've been tuning per the owners manual and what I have seen online. Anything under the secondaries opening it runs like a dream.

Time for a 1050 dominator lol.
 
back in the day, guys used to reduce the mass of the counterweights, to quicken the secondary air door opening. It sounds like you need to slow it down a little, but I don't know, off-hand, how you could temporarily add weight to the counterweights to test that theory.
What rear axle ratio are you running? how tall of a tire?
 
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