2500 stall or 3000 stall?
My calculator estimates that you will need about 310-320 RWHP to get that heavy car into the 13.75 range. You should be close.
I still think you might need a little more than 3000 stall with that weight.
I would guess about 3500 stall. Don't take my word for it though. I would call one of those converter places and ask them.
Get the right one the first time so you don't end up doing another converter swap.........like I did!
351w(.060), ported & polished heads with 1.94/1.60 valves, 10.3 comp, stealth intake, 274XE cam, Holley 750 dp, Mallory dist., shorty headers, flowmasters, 4:10 gear, c-4 with 3700 stall converter, subframes, electric fan