I work for aamco trans and i have the follwoing choices for converters 2300-2500 stall 12" lock up 2400-2800 11" non lock up 2800-3200 10" non lock up My mods are in my signature car will be getting 3.70 gears soon too. Keep in mind the car is carb and look up doesnt work since there is no longer a computer. It is a street strip car drive the car atleast 100 miles a week.