get the 2000 stall....
the 2000 means that if you were to lock the rear end (ie tranny brake) and mashed the gass peddle, the converter would only let the motor get to 2000 rpm...
I think stock is around 800 or so...
I have a 1800-2000 in mine, and I can let my foot of the brake and it will begin to roll at idle, so no you don't have to go to 2000 to take off from a light. It dose grab a bit higher (you can notice you don't have to hit the brakes as hard to keep it stopped at idle in gear) but not too much so...
I wish I would have gone a bit higher myself, and will next time, but 2000 sounds a bout right for you....
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69 Camaro among other toys.