[My427stang]

Try to take it very scientifically, at first especially

- Verify with someone else on the throttle (not running) that the throttle is opening all the way
- Check the initial and total timing to ensure it is where you want it, and that it is advancing
- Review the firing order and make sure you have it correct
- Readjust the valves if you have solids
- Check how close the air cleaner lid is to the top of the carb

Dont ever discount bringing a good mechanic in for his ear as a backup plan, even if you only pay him to listen. Often it can go a long way