how large of a carb can perform well on stock 273 commando ?

Well ...... after screwing around with larger carb I went back to the original 500cfm afb.. engine just did not like that 650 dp holley.. too much .
after intalling the original afb .. the 273 loved that ..
great throttle response and revved FASTTTTTTTTT.
after I got the carb all tuned in to that new ld4b .... Relashed the valves again .... quite a few were tight after lashing them cold. now they are 21 and 13 HOT. took her for a BEAT RUN .......... AND ...... What a difference with just switching to the ld4b.. More torque and Power... Now at a roll in 1st gear ... just jump on her and it swauk the tires and get rubber out of second gear... never did that before .. All this with just an ld4b intake change.. and you would not believe how it pulls on top end now. This is all with a stock 273 never opened up. right from chrysler. Dougs Headers will go on in a couple weeks and then may try going up on the carb some.. also .......... 2.93 Gears are coming out and 3.55 are going in ... this 273 is going to be a beast !!..
I had a bunch of 340 darts and cudas over the years .this 273 feels just as fast .. think this engine is a littlle freak .. just keeps getting faster as I tweak it.
has a lot of potenial yet.
I'll keep you post on the updates.
john