carb adjustment

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gotdust57@yahoo

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i have a edlebrock 600 or 650 cfm 4 barrel on my 73 360 duster, and just cant get 4 barrel to kick in, i give it full throttle 4 barrel lever moves but butterflies wont open, i see a type of spring next to lever is that the adjustment to open it or does anybody have any ideas, frustrating when you want to kick it down. also cant get passing gear to kick down it has aftermarket lokar on it and when i adjust it it just changes shift pattern, any help would be thankful
 
Have you checked if the secondary butterflies will open without the engine running, put your fingers inside the secondary air valve and open the throttle all the way (WOT) and look inside. either the opening in the manifold is blocked, or the secondary butterflies are stuck shut if they dont open. the kickdown probably wont work right until you have full travel on the carb linkage. The other item to check is the cable adjustment on the throttle linkage. It should have almost no slack in the cable at curb idle.
 
i tried with engine off they seem to be open just about quarter of way before i touch them, them when i stick screw driver in i can open them all the way. but dont open all the way with wot engine off. i tried tightening the throttle cable to get slack out but when i do take the slack out i lose alot of peddle travel on inside then i put alittle slack in it and my peddle travel comes back. let me throw this at you somebody before me had put aftermarket lokar kickdown linkage on it and the braided cable is frayed and loose where the adjustment is on it so i adjusted it at the little set screw it has that changes shift patterns but no passing gear could this aftermarket lokar be junk and will that have something to do with 4 barrel not opening up? i am truly thankful for your help thanks
 
Well, try removing the lokar cable off the carb, the throttle cable and see if the carb opens all the way with the engine off, maybe the lokar is not adjusted correctly. Sounds to me like the lokar kickdown is the problem, alot of people have issues setting these up without guidance.

The lokar kickdowns work really nicely if they are set up correctly. For more info on how to set up the kickdown look at Bouchillon performances website, they sell a mopar kickdown that is similar to the lokar, open their installation instructions and you can then see how yours should work.

If you cant get the carb to open without a screwdriver something is wrong. I'd take the carb off and inspect it for problems. Could be alot of things.

Is your choke adjusted and working correctly ? If the choke linkage is inplace and not set up - the secondaries may not open either, primarily if the choke fast idle linkage is bound up it will screw up the secondaries.

It sounds to me like you need to start over, meaning pull the carb, inspect it. Make sure there is not something wrong with the manifold opening for the carb. If its okay then reinstall the carb, check for WOT, if okay, set up the throttle cable adjustment, then hook up the lokar kickdown. If the lokar cable is really frayed it may cause issues, it should move smoothly.
 
i have electric choke with dial and is set in middle of dial, i can get secondaries to open with screwdriver i will try taking the lokar off and try some of your other suggestions and let you know thanks for help i am not much good at carbs but know how to check things. thanks again
 
If the primaries aren't open you can't mechanically open the secondaries. Even though the secondaries open based on vacuum the primaries limit the amount they can open until they are open all the way.

Also, the secondaries will not open by giving it gas when the car is not moving. You need the load of the engine moving the car to get the air velocity high enough to cause the secondaries to open. If they are working properly you won't feel them open.
 
DGC is correct, you must open the throttle by opening the primaries via the pivot connector where the throttle cable connects, the air valve can be opened with your fingers and you can see if the secondary butterflies have opened. Make sure the choke is not interefering as well, make sure it is not stuck on the high idle cam.
 
Pull the carb off the engine!!! You have something WRONG! If the secondaries will not open all the way (and easily) by hand there is a problem. Until you resolve this DO NOT UNDER ANY CIRCUMSTANCES DRIVE THE CAR!!!! If you don't know why the throttle will not open all the way, how can you be sure the same problem will not prevent them from closing? I learned this the hard way with a Q-Jet at full honk on a twisty mountain road. (In this case it was a defective base gasket).

It is the actual secondary throttle blades and not the air door you are moving with the screwdriver correct? If so, stop doing that before you really ruin the carb. As others have suggested, remove the kickdown linkage first and make sure the carb gets WOT when the pedal is floored. You do have the "Mopar throttle lever adapter" fitted to this carb right? If the throttle cable is somehow attached to the big hole on the carb arm, it won't work. Once the throttle linkage problem is resolved, and only then, do you stand a chance of getting the kickdown set up right.

A malfunctioning throttle is like malfunctioning brakes. Both are serious safety issues. If either cable is frayed or sticking, replace it before it kills you.
 
i dont think i have mopar throttle lever adapter could you send me pics of one, or give me your e-mail address and i will send pic i cant get it to work through this site is alwasy says files are to big, also i think i have the 4 barrel working but at take off when i mash the gas sometimes it wants to dog down and then take off, please let me know abot mopar throttle adapter as this carb was already on when bought, i just put in 360 and used same carb setup. thanks
 
The adaptor is Edelbrock Part # 1481 http://store.summitracing.com/partd...400065+4294839063+4294844433+115&autoview=sku

The nice thing about this part is it allows you to run the stock throttle stud and kickdown linkage. I'm not trying to bash the aftermarket stuff, but the factory parts work well here.

If you have a bog with an Edelbrock, something is screwed up with the air door., or the carb is way out of whack (assuming the ignition system is OK).
 
new pertronix 2 ignitior and flame thrower coil, no problems till i started trying to get 4 barrel to work, now seems to work but bogging out on fast take off since my 4 barrel is working now will i need to adjust timing to accomadate? thanks
 
Probably no need to adjust the timing, if it is set reasonably (10-15 degrees static, 34-36 total). Just make sure everything is up to snuff. Fix any possible vacuum leaks. Don't start second guessing things, and don't change more than one thing at a time. A bog can be caused by several things, but start with the carb since your ignition system sounds to be OK.

First, download the Edelbrock manual for your carb, read and heed.

Next, start out by setting the carb to the factory baseline. (For an Eddy 1406, thats .098 primary, .095 secondary jets and a .075 x .047 rod, with yellow 4" step-up springs.) Make sure the float level is correct (11/32"), accelerator pump is in center hole, and make sure you have a good fuel pump and a new fuel filter. Disconnect the vacuum advance hose, and cap it at the carb. Now test drive the car. Better?

Personally the next step I use to dial out a bog, after setting everything back to stock, is to REDUCE accelerator pump shot (outer hole on an Eddy). This should make it worse, verifying you are leaning out. More than half the time I have found that people set the accelerator pump way rich and the overwhelm the ignition system with fuel, especially with Holleys.

If you do want to play with the timing, and by all means do so, try advancing 5 degrees. Unless there is a HUGE improvement, that wasn't the problem. Get the carb right first, and do not change more than one thing between test drives.
 
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