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Discussion Starter #1
All,
I'm refreshing a pair of DCO3 carbs, tightening up the linkages with new parts, etc and will be synchronizing the carbs on the car.
Any tech tips or point me to an existing thread would be appreciated.

Jim
San Antonio, TX
 

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dco 3 carbs

Jim,

make sure the links going to the carbs from the throttle rod are the same length. to begin with, loosen the levers on the rod so that the carbs can be independently set. use a mirror to set each carb throttle screw and set at 1/2 turn out (after initial contact with the throttle lever.) set the idle mixture screw out 3/4 turn from fully closed (make sure when closing the idle mixture screw that it is not turned down tightly - otherwise will distort the idle mixture port.)

make sure the jets are the factory settings. idle air jet should be 120 not the initial (early) 175 jet. idle jet should be 50. main jet should be 105/110 main air should be 190/200. factory setting for the choke is 28 aux venture 4.5.

I've never been able to use a unisyn tool. use the old tried and true listen with a tube/hose whereby the sound of the air is the same for each cylinder to set the balance.

when you re-conditioned the dco 3's how did you set the float. it should be 23.75 mm below the base of the carb with the float 3-4 mm below the base. very difficult to set when on the engine. so set prior to instillation if possible.

Reed
 

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Discussion Starter #4
Reed,
Thanks for the input. The carbs are jetted as you've recommended and I'll be setting the float height on the bench. Parts coming from Pierce Manifold.
I'm having trouble finding flange mount gaskets for the DCO3. Any sources you know of?

Jim
 

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Reed,
Thanks for the input. The carbs are jetted as you've recommended and I'll be setting the float height on the bench. Parts coming from Pierce Manifold.
I'm having trouble finding flange mount gaskets for the DCO3. Any sources you know of?

Jim
Use an old hose section from a radiator or such with a 90 degree bend it it. Works like a charm.......you probably/might have to take the airbox off to get clearance. Oh, sorry I misread .. that was for the Unisyn. I've never had luck with the hose to the ear method. Flange gaskets? Scissors. Uncle
 

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Discussion Starter #6
Thanks Uncle,
I've been using the German made sychrometer for tuning. One of the accessories is an elbow shaped rubber adapter. Perfect!! At least for 105 DCOE with ample room in the plenum. Won't fit the 101 sidedraft plenum.

Jim
 
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