Alright, next carb thing to check - dwell. To attach a dwell meter do I just clip to outside of green wire off the MC and clip to metal for ground?

 

You don't have to dig into the wiring- the factory provided a single wire, flat blade connector hanging out of the wiring harness for this purpose. I recall it's somewhere around between the carb and alternator, if memory serves and I beleive it's blue or green in color. + goes to that connector, - goes to a good ground location of your choosing. Check dwell to your heart's content.

 

The dwell terminal on my '84 T/A in on the computer harness near the blower motor/HVAC case in the engine compartment. Its a single green connector.

If you have a engine computer scanner you can also get the M/C dwell and other sensor data through the ALDL connector under the dash inside the car. I borrowed a GM TECH 1 scanner to set up the carb on my car.

 

Thanks - pretty sure I remember a drk greenish wire near fan hanging free - I'll have to see if coffee confirms this

 

I connected a dwell meter & on 6 it reads ~26 when wamed up (~34 when cold). cold starts after 3-4 hours are still little rough but car starts. Are these good dwell readings?

 

The dwell should be varying when the engine is warmed up and in closed loop mode. The needle should wig wag back and forth. You want to check the dwell with the engine fully warmed up(closed loop), transmission in drive, A/C off, and base idle correctly adjusted(usually 500 RPM in D.) Its best to take the car for a quick drive to make sure its in closed loop mode. Also make sure the TPS sensor is(.48 volts at base idle, engine off) and base distributor ignition timing are properly set. You want to get the dwell varying close to 30 degrees. Varying between 28 and 32 is about where it should be. Depending on the carb model number, you turn the Idle Air Bleed or equally turn the two mixture needles in the carb base plate to set the M/C solenoid dwell.

 

Yeah, around 30* is where you want it when you're in closed loop. When the motor is cold and running in open loop the dwell is read off a pre-programmed table in the chip and won't change when you alter the A/F ratio. You gotta have the O2 sensor putting in it's 2 cents worth (closed loop) before the ECM will start trimming the dwell to try to achieve stoich.

 

Um, I didn't have it drive, so that'll make a difference. I followed everything in your guys posts except taking a TPS sensor reading at 48, and then the actual adjustments (I have the ccc carb). I will look at a diagram to locate adjustment screws but where is the TPS sensor reading taken at? Thanks, this is helpful -

 

You need to back probe the TPS sensor connector with some metal needles on the B and C terminals and connect a volt meter to check the setting. It should be 0.48 volts at base idle.