Finetuning questions - do I need a high-stall torque converter ?

Hi everyone!

I don´t know how to continue at the moment.
I am generally happy with my setup - but the car could launch better and I´m not able to do a burnout. The engine just goes up to 2200rpm (converter stall speed) but seems not to have enough torque to spin the tires. Either the carb is not yet set up properly, or I need a torque converter with higher stall ? Has anybody same experience with the cam I use ?
Have tuned the carb in with an AFR meter - could not identify lean or too rich spots.

Here are the specs of the components I used:

67 Dodge Dart
318 bored to 323
273 forged crank & rods - pistons weight matched to have a balanced set-up.
Hughes HUG HEH1928AL cam
Intake Lift .489"
Intake Duration at .050" 219°
Lobe Separation Angle 111º
Intake Centerline 108º

Edelbrock Thunder 500 AVS
/6 torque converter - stalls at around 2200 when I hit the brake and full throttle.
Heads are cast iron standard heads, ported as far as possible
TTI Headers 1-5/8" O.D. primary tubes steps up to 1-3/4" secondary tubes with 3" 3-bolt collectors

310hp on the chassis dyno
3.23 sure grip 8.75
225/70R14
beefed 904

ran a 14.1 on my first quarter mile run, letting the trans shift

Should I go for a new torque converter with 2500 stall ? I read that the efficiency of a custom made converter will be better than my /6 converter. Or is this money spent needlessly ?

I´m fancy with this one: http://www.edgeracingconverters.com...4-transmissions-p-16.html?number_of_uploads=0

Appreciate your thoughts!
Lars