Poor idle and off-idle performance after distributor swap

I have a stock stall converter, 727 auto and 3.23 gears, don't want to go any taller as this car regularly sees 85 on the freeway. Very happy with the current gear combo. It runs so darn good with the 500 cfm, I guess I am just losing power on the top end. But this is a daily driver, has plenty of power and feels very strong. Will be nice to get some more on the top end but I am not about to swap to a spread-bore intake and carb for a small improvement in power. Already have the 600, might as well play with it.