Torque converter or no?

You can use a stock converter, but it will slow your car down. A stock 1000-1100 rpm converter will apply full load to the drivetrain before your engine "comes on the cam". It will certainly work, just not as well as it could. Using a higher stall converter allows you to make better use of the power and torque you are getting from your modified engine. For a high performance street only car, I generally like to use a converter that stalls between 2500 and 3500 rpm, depending on the engine torque, rear gear and vehicle weight. The more torque you have, the lower the rpm can be, but I wouldn't recommend less than around 2500.
For a car that sees drag strip duty, you generally want the converter to stall at an rpm near the torque peak of the motor. Usually between 3800 and 5800. Regardless of what rpm stall you chose, a good external transmission cooler is a necessity when using a high stall converter. A high rpm converter builds a lot of heat due to hydraulic friction.