The problem with less gear and a relatively tight stock type torque converter is the rpm drops on the shifts pull it out of it's power band. Even with the well split 200-4r, and 4.56 gears, shifting at 5,700rpm with a 27" tire drops the rpm's nearly to 3,200rpm (not accounting torque converter slip) and it just takes time to pull it back up to 5,700rpm again. That's the only reason I don't want to switch to taller gears, like 3.42 to even 4.11's.
Rebuilding an OHC Pontiac 250 with EFI and a Turbo