What would you check next?

[BigMeatyClaws]

1985 with feedback 2150a carb. I have a stalling issue at the beginning of acceleration. The engine stalls like it is going to die then picks back up if I stick with it on the gas. I also have knock under load. Timing is good. Accelerator pump and diaphragm are good. Power pump is good. Appears to be running rich per black exhaust. No idle issues, except the idle air mix screws don't seem to be very sensitive to change. New coil, wires, plugs, and distributor cap. 22 hg vacuum and steady. What would you check next? Float level? Battery voltage? Back up light fuse?

Many thanks

 

[Uncle Gump]

Leaky needle and seat... heavy float

 

[MadMax_636]

Test your fuel pump, buy and use this Carb, get these gaskets, get a 1 inch or so plastic spacer.

Rip out all the original ignition system and do the GM HEI + Duraspark mod. It will help you with keeping things simple and working. The feedback carb is garbage. There is zero use/point in trying to tune and get it to work right. Get a new one.

Same with the GM HEI + Duraspark system will help you keep it simple, clean, and back to the basics of ignition system. No extra vacuum crap.

 

[kimcrwbr1]

If your still running the computer adjusting the needles is pointless as the computer is controlling the engine idle. Disconnect the battery and short the pos battery cable to ground. Turn the slow needles to lightly seated then turn them out 3 full turns. Then connect the battery and start it up. Pull the power valve hose between the slow needles under the front of the carb if you smell fuel in the hose your power valve or gasket is leaking...

 

[franklin2]

Original thread starter has another thread on here where he converted to a duraspark system.