need a little carburetor help

[c10chevy69]

I have just finished installing an Edelbrock 1405 carb on to a 350 w/auto. It idles fine but it idles a little rough while in gear. On the road test it dumps a little black smoke out of the tailpipe after I let off and then step on the gas. Also I am not sure if this is running the right type of air cleaner (large line from pass. side valve cover to what seems to be a three inch spacer between carb and air cleaner. any trouble with going to an aftermarket one? Thanks for the help.

[john]

There is no problem with aftermarket air cleaner, it will come with a fitting to hook your valve cover vent hose to. John

[RON WOODGEARD]

You're going to have to do a little adjusting on the carb. Buy a Carb. tune up kit. It will come With needles, and jets, of varied sizes. The needles will be of different thicknesses, and they will be tapered. most a three taper some only two. You will want to take one of the thickest needles and install it. this will allow less fuel to go into and through the jet. If it's really overloading the engine with fuel, you may have to take the top off the carb and replace the jets, and play with needles. To change the needles there are two little round plates that have a single small round screw holding them down. remove those and the needles are in there attached to a small arm. this arm lowers and raises as the vacuum changes, so when the engine is at idle, the vacuum is at it's highest, ( strongest) this holds the needle down into the jet so only a slight amount of fuel can pass through the jet. When you push on the gas peddle, the vacuum starts lowering, and the needle starts raising or Pulling out of the jet. this is where the taper comes into action, the taper allows more fuel to run into the jet as the needle gets smaller in diameter,(Tapered) When you have your foot to the firewall.
You need to "TUNE" this action together to get the best economy, and performance out of this carb.. Once you get into it, you'll see how the action works. that's one of the things that makes these carbs so great. you can tune completely through the RPM range unlike the Holley that only has a jet for the fuel to run through.

As a side bar,,, These needles can be bent very easily, so be sure they are seated in the center of the jet before pushing down on them.

If I failed to make something clear here,,,, there are books explaining this along with pictures.. The pictures really show and makes things easier to understand.

[Russell]

here is a manual on the Q-Jet released by the manufacturer Very good resource, but a bit of dry read. It does have a full step by step rebuild tutorial though!

http://www.tocmp.com/manuals/Carbs/R...QJet/index.htm

[72C203503ONTHETREE]

Make sure the choke plates are opened up also, they will make the engine run overly rich if they dont open.