Sorry kind of long but wan't to give as much back ground as possible.

Ive got an 85 305 LG4. Completely rebuilt, new O2 sensor, Coolant temp sensor, new wires, plugs, cap and rotor, carb gasket and vacuum lines.

The carb that was on the motor originally would not idle correctly. It would jump 30-60 rpms. Past idle it didn't run too bad. I had to take it off because I had to idle at 1000 in park to keep the car from dying when put in gear.

I put on a different quadrajet, I got off ebay. Apparently it was rebuilt some time ago. The cover over the IAB was removed and the body cast on the passenger side, that limits the secondary travel has been filed off.

Now the car is running too rich. Timing is set at 0 degrees as stated on the label on hood. The idle mixture screws are about 5 turns out.

I checked the MCS dwell, I think I did it right, and it was pretty steady at 55 degrees. If i reved up to about 2500 Rs it would drop to about 25 degrees then settle to about 55 again.

Any ideas or tips?

 

The dwell meter should be set on the 6 cylinder mode. Dwell at idle should be in the 30 degrees range, if memory serves.

A little more base timing may help. The factory was rather conservative on that.

 

Thanks five7, I had the dwell set i the 6 cyl range. Does the car need to be in gear to check the MCS or warmed up and idling. Should I move the timing to about 6 or 8 degrees?

To check the dwell of the MCS, I am putting the probe into the green wire that plugs into the carb. That is correct? I am also leaving the MCS plugged in, should I unplug?

Another thing I think is happening is if I go a steady speed 40-45 then have to speed up the car seems to hesitate. I am not talking about full throttle just more throttle to pass. Could this all be related?