[T Bird]

CDN914
You don't state under what circumstances you experience "popping from the tailpipe." Does this occur under load? At idle? Above/below 3000RPM? It makes it hard to diagnose whether you have a carburetor problem without knowing a bit more. Popping or banging in the muffler can indicate a lean mixture. However missing is another matter and suggests to me an ignition related problem. If the mixture is lean enough, you will get some really nasty spitting through the carb barrels. Is this what you mean when you say that your engine is "missing?"

I would not start replacing jets unless I was first certain that the carbs were set up properly (float levels, accelerator pump volumes, balance and idle mixture adjusted correctly). Assuming that you were able to eliminate these adjustments as possible sources of the problem, I would take a look at those idle jets. If I'm remembering correctly, the factory idle jet for the 2 liter was a 45. That's a wee bit small for today's gas. 50 or 55 should solve lean popping.

I don't understand your statement that you can't get the engine to "run rich." How do you know? Are you using an exhaust gas analyzer? If so, that further suggests the need for larger idle jets.

jft914- I'm glad that my Weber set up instructions have helped you.