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Edelbrock uni syn


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i couldnt find the vid... but i place it over cylinder one air horn and turn the adjusting screw all the way in and out and messed with the idle mixture screw in and out and i couldnt get it to read anything... the float never moved... do i need two at the same time on mikuni's... i tried covering the 2nd air horn on the same carb and nothing tried messing with the idle... im not sure whats happening ....im gonna keep researching but im suck

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the unisyc does nothing for the mixture screws

Its only to make sure both butterflys open at the same time.THATS IT!!!!!!!


On my mikini set up i do the 2 inner most horns. I rev the car up to about 1500 to 2k and I put the sync on and see where the ball/needle goes before it kills the airflow. There is a adjustment for this to let a certain amout of air on the sync. to let more or less air thru the sync.

But I just keep a constane rev and see what one carb does. You will try to match them up. and then see where its at at idle.


the carbs will have a idle stop screw that can be adjusted also.at least mine do.

adjust between carbs you adjust the arms f you have qa 2 arm set up. or if its a center pull set up youll have to adjuts the stop and there will ba a tenstion screw type set up to adjust between the carbs, and the idle stop.


Unisync dont adjust mixture. this youll need a exhaust O2 set up oe do a best guess on that. 1.5 turn from bottom? Im only guessing

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ok thanks hainz yea... i was reading and reading all last night and i figured i would do 2 turns on mixture screw since thats what i had it at before and it was working fine... then rev it up to about 2k and i nead to match the 1 and 3 and the 2 and 4... so ima do that today.. once again thanks hainz

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i do the 2 inner runners. so that would be 2 and 3

2 of the first front carb and 3 the rear carb set i use the unisync. I have to assume the butterfly plates are the same for the ajoining one so no need to measure them unlkess you think a plate got bent from 1 and 2 as its in the same carb. hope you understand this. If plate /shaft is bent on one carb(1&2) or #&4) then youll never get them correct.

I assume you have dual choke sidedrafts like a DCOE. or Mikuni PHH series.



example 1 carb has 2 barrels. I have to assume the plates are exactly the same when they open.

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I do 2 & 3. I put it on for a second or two. what usuaully happen is the ball will go to a certain point. Just remeber that point then it will usually lower abit.

I do the high part of where the ball was it. and go between cylinders2 and 3 till you get it even. if you want to ck 1 and 4 thats up to you. Maybe 1and 4 is better as its the far most plates to ck. But this is what I do.



as for adjustment I dont know what you have.

I dont know if you have a 2 rods the push the carbs or you have a Center pull system.

The DCOEs might even be slightly different system. youll have a to post a photo or just figure it out how your linkage set up works.



My Mikinis has 2 rods that push each carb. at the ends its threaded like a turnbuckle. turn it in/out to make the rod longer or shorter. then there is a idle stopper adjument.

My Yellow car has a center pull system but to lazy to expplain it!!!!!!!!

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well i have the 2 rods that push each carb... its an l20b with 87mm flat tops u67 ported polished big cam dual springs... it has like 3500 miles on it i have the timing a bit retarded and some colder plugs... ill post of pic of my carbs... i think like 1 and 3/4 turns on the mixture maybe as a ball park or 2 turns.



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yes you would ajust the rods. its like a turnbuckel. loosen the jam nut on both side and turn the center part cw/ccw wise to get what you want. Looks like a turnbuckle Im not totally positive as photo is so so. otherwise its lock the arms in the correct spot on the horz bar

als at the base of carb near the bottom of the rods there is a stopper,you can adjust that also ,this tell how much the plate is open(when its closed) this sets the idle speed. Might be hard but you get the idea.


since you have a L20w/flttops dont you have detonation proplems? most dual carbs you want 12-15 intial adv. You should run good gas in this otherwise you ight really have to retard the ignition but you wont get full power.

Im sure you put 100octanne and adv to 12-15 it goes good!

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yes when i ran 100 octane and 15 degrees advanced the motor felt strong but when i would go past 1/4 throttle it feels like the carbs arent balanced and struggles then when i get to full throttle it just pulls amazing but i would like to be able to open more than 1/4 throttle and not have the carbs stumble in the case of hills or freeways and such... so ill check if the rods are adjustable and if not i would just adjust the stopper correct?

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well it might not be carbs are that far off usually they spit ans spatter a bit if ot ballanced. You can tell by looking if one arm is opening the carb more than the other.

Could be a jetting issue


I think if you have 44s you want close to 240 air and about 160main would be a base line.

My 40s are 160 air 135 main


make sure the jets are screwed down and nothing blocking them. Maybe pull out the jet blok ans see if anything blocking.


You sure your cam is timmed?If a L20b you probaply want to start on sprocket #2) make sure the marks line up. If OK , Maybe try another distributor(I am reaching on this one but you never know)

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open more than 1/4 throttle and not have the carbs stumble in the case of hills or freeways


this is a key statment, thats you mentioned


aligned the carbs best as you can.


Mikunis (I Believe) have a low/med and high speed circut. might be a trasition issue.


so I would be just guessing but since you have a HI comp L20 which I do not like for the street when running pump gas. You mostly retard the dizzy to keep from pinging. But really you want the most adv as possible right up till it pings. So add these factors, possible a Dizzy adv issue, and maybe a slight jetting issue could combine to be a big thing.since these are 44mm carbs I assume you dont have a vac adv(i never seen one). If you do make sure its to the carb and not the intake manifoldgood luck as Im out of guesses.

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alright guys update... i installed a new hood release cable... took out the jets and cleaned them ...they are main air jet say 210 on top and at bottom 165...pilot jets say 165 all others same... is this good or any suggestions?... it is cold today and i went to del taco man it ran like a champ... and the 510 lift cam transitions really nice

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